Cultural Influences on Infant Sleep

Cultural Influences on Infant and Childhood Sleep Biology, and The Science that Studies It: Toward a More Inclusive Paradigm
James J.McKenna Ph.D.

Professor of Anthropology and Director,
Mother-Baby Behavioral Sleep Laboratory
University of Notre Dame

Published In Sleep and Breathing In Children: A Developmental Approach JLoughlin, Jcarroll, CMarcus, (Eds.)
Marcell Dakker 2000, pages 199-230

1. Introduction
"...we try to keep in mind cultural influences on the advice we give. We remind ourselves that much of what comes to the pediatrician's attention, as problematic sleep behavior--children who have difficulty falling asleep alone at bedtime, who wake at night and ask for parental attention, or who continue to nurse at night--is problematic only in relation to our society's expectations, rather than to some more general standard of what constitutes difficult behavior in the young child. Our pediatric advice on transitional objects, breast feeding, cosleeping may be unknowingly biased toward traditional Euroamerican views of childrearing, especially those about bedtime and nighttime behavior. Thus, in giving advice about sleep, pediatric health professionals might do well to be aware of their own cultural values, to examine closely their patients cultural and family contexts, and to assess parental reactions to children's sleep behaviors" (1).

"Who sleeps by whom is not merely a personal or private activity. Instead it is social practice, like burying the dead or expressing gratitude for gifts or eating meals with your family, or honoring the practice of a monogamous marriage, which (for those engaged in the practice) is invested with moral and social meaning for a person's reputation and good standing in the community "(2)

"In clinical pediatrics, cosleeping is the political third rail. If you touch it, you die" (3).

In this chapter, I provide a cultural background to our thinking about what constitutes "normal, healthy and desirable" infant sleep and show the interconnectedness between scientific research, cultural values, concerns for morality, and sleeping arrangements characteristic of Western society. Specific biological and psychological evidence is put forth supporting Sadeh and Anders (4,5) and Ander's (6) views on the importance of understanding what is "appropriate" infant sleep based on the overall social and physical context within which it occurs.

To illustrate this viewpoint I selected data on a variety of topics demonstrating how culturally guided parental childcare choices, including those involved in sleeping arrangements, set in motion a cascade of interconnected changes that affect the biology and behavior of the participants, appropriate to those choices. I suggest that clinicians generally fail to convey to parents the legitimacy of different choices, and that the widely accepted research paradigm fails scientifically to include alternatives to the model of the solitary sleeping, bottle or minimally breast fed infant. The diversity of sleep-related arrangements and practices alter infant sleep development significantly in the first years of life and this argues against a simple cultural definition of infant sleep progression implied by the widely accepted (traditional) model.

Relatedly, perhaps no other issue has been so often misrepresented and grossly oversimplified as parent-infant cosleeping. New data on the subject highlights the extent to which cultural ideologies, cultural judgments and concerns for morality often are mistaken for science, in this area. For example, data collected exclusively on the solitary sleeping, bottle-fed infant continue to provide the basis for definitions of, and research into, clinically "normal" infant sleep-wake patterns. These data continue to serve as the gold standard against which, eventually, parents and professionals evaluate infant sleep development, despite significant contextual differences which may invalidate the comparisons. Almost no consideration is given to other sleeping arrangements, however healthy they are.

New data from psychology are presented which raise the possibility that clinicians have overestimated the need for infants to sleep separately in order to assure "independence"from their parents, and recent biological data described here suggest that sleep researchers underestimate the importance of maternal proximity and breast feeding in regulating infant sleep physiology, and, thus, fulfilling infantile nighttime needs. By using data from only one type of sleeping arrangement and implying that there is only one context within which healthy infant sleep emerges, i.e. the solitary one, pediatric sleep research is thus held captive by Western ethnocentrism.

I conclude that to forge effective partnerships between parents and health professionals in our ever increasingly mutlicultural society, pediatric sleep medicine must come to terms with cultural biases embedded in sleep research medicine in general and clinical interpretations and advice in particular. At this point in the history of western societies, where an unprecedented convergence of cultural practices is underway--- not the least of which involves sleeping arrangements--- it is critical that clinicians and researchers broaden their thinking about what constitutes appropriate and desirable childhood sleep practices. Failure do so will continue to limit both the accuracy of pediatric sleep science and the effectiveness of care.

2. Culture and Childhood Sleep

The importance of local cultural influences, including health professional and family values on infant and childhood sleep, was anticipated more than a decade ago by Lozoff and her colleagues (1). In the first of the three passages quoted above they acknowledge as eloquently as any group of anthropologists or psychologists the critical, if not pivotal, role that personal beliefs, experiences, and societal values can play in pediatric research. The same applies to the advise given to parents regarding a range of nighttime sleep related issues, problems and possible solutions. Across different cultures, ideas vary about how, where and why infants and children should sleep, as well as what constitutes "normal" sleep and "sleep problems" (2,7,8). Ethnographic studies of this variability worldwide are important because the data help to establish the extent to which specieswide sleep biology and development are subject to environmental manipulation and regulation. Local customs and traditions, irrespective of whether the society is industrialized or is structured around a hunting and gathering economy, all play roles (9-14).

Even within a single society, infant and childhood sleeping patterns and the social values and relationships that influence them are diverse, and significant differences cut across subgroups in unexpected but important ways (15,16,17). For example, infants and children not able to sleep alone and "through the night" are not uniformly regarded in our own culture as having a "sleep problem," Anders and Taylor (8) point out. Most conceptualizations of "sleep problems" are based on culturally and parentally constructed definitions and expectations, not biology. In reality, infant sleep development plays out extraordinarily differently in diverse family settings wherein infant feeding and nighttime nurturing behaviors, and parental needs and goals, vary. These, in turn, affect both long and short term developmental processes. Yet, the legitimacy of these variations continue to be largely ignored in both professional as well as popular discourse and a "one size should fit all" approach to sleeping arrangements continues to be advocated (cf. 18).

2a) How Do Social Values and Cultural Goals Influence Infant Sleep Practices?

That a critical relationship exists between the cultural ideologies that underlie sleep practices and desired developmental outcomes (even when they are not achieved) is made dramatically clear when one compares Asian, Guatemalan, and American values, conceptualizations of infants at birth, and desired developmental outcomes. For example, interdependence and group harmony are positively valued in Japan where parent-child cosleeping is practiced. As Christopher describes it "One monkey that does perch on the back of nearly all Japanese is a deeply engrained feeling that individual gratification is possible only in a group context--a feeling which like the taste for dependence, clearly stems from childhood experiences" (19).
American children are presumed to be trained to be self-reliant and to display their individuality by sleeping alone, and Japanese children are taught to "harmonize with the group" and, hence, "cosleep" with their parents. These observations relate to the different attitudes that Japanese and American parents have concerning the"nature"of the infant at birth, what developmental outcomes are desired, and what sleeping arrangement are presumed necessary to achieve them. For example, Caudill and Weinstein (20) cited in Shand (21) state that:

"In Japan the infant is seen more as a separate biological organism who from the beginning, in order to develop, needs to be drawn into increasingly interdependent relations with others. In America, the infant is seen more as a dependent biological organism who in order to develop, needs to be made increasingly independent of others".

Indeed, according to Brazleton (22) "...the Japanese think the US culture rather merciless in pushing small children toward such independence at night". Kawakami's (23, cited in 24) describes American and Japanese differences this way: "An American mother -infant relationship consists of two individuals...On the other hand, a Japanese mother infant relationship consists only one individual i.e. mother and infants are not divided." Japanese infants and children usually sleep adjacent to their mothers on futons with space availability playing a minor role in this arrangement, and in general children sleep with someone (fathers or extended family members) through the age of 15 (24,25).

Similar to the Japanese, Mayan mothers from Guatemala do not believe in separate sleeping quarters for infants, children and parents. In fact, sleeping alone is considered so difficult for adult Guatemalans that in the absence of family members it is not uncommon for adults to seek out friends with whom they can share sleep (24). Upon hearing that American babies are made to sleep alone Mayan women respond with "shock, disapproval and pity" and think of the practice as "tantamount to child neglect" (24). This evaluation contrasts dramatically with one offered by Ferber of the United States who advocates that all infants should be taught to sleep alone. In his popular selling book How To Solve Your Child's Sleep Problems , Ferber provides mothers who may be emotionally predisposed to sleep with their infants with a reason to ponder the status of their own mental health..He advises: "If you find that you actually prefer to have your child in bed, you should examine your feelings very carefully..." (26),

The study of Guatemalan (Mayan) women is one of the best cross-cultural (comparative) studies of childhood sleep to date. Morelli et al examined a group of middle class American (Caucasian) and contemporary Mayan (Guatemalan) mothers and found that all the 14 Mayan mothers slept in the same bed with their infants, and 8 older toddlers slept with their fathers. In the middle class American sample, none of the newborn infants regularly slept with its mothers. Mayan parents believe that cosleeping is the only "reasonable way" for a parents and infants to sleep, while the Americans in Morelli's et al's sample felt comfortable keeping newborns and neonates next to their beds "to make sure that they were still breathing" (24 ), but were not comfortable having them in the same bed. After their children's third to sixth month of life, the Americans parents felt their infants were no longer so vulnerable. Fearful of interfering with the infant's progress toward independence and autonomy, most American parents in the sample moved the infants to a separate room.

In another study, conducted in Australia, an immigrant Vietnamese mother was told about the sudden infant death syndrome (SIDS), with which she was unfamiliar. She surmised that "...the custom of being with the baby must prevent this disease. If you are sleeping with your baby, you always sleep lightly. You notice if his breathing changes...Babies should not be left alone". Further to the point, another of the Vietnamese mothers added: " Babies are too important to be left alone with nobody watching them" (27).

Of 40 Chinese women interviewed (in Chinese) at Guagzho University Hospital by Wilson (28) over 66% of new mothers were intending to have their infants sleep with them in the marital bed, and all of her sample were planning to have the infant sleep alongside the bed. One informant represented many when she stated that the baby is "too little to sleep alone", and that cosleeping "make babies happy". Another Chinese informant tells Wilson: that "...the parents breathing effects the baby so cosleeping is good" and, later, cosleeping permits mothers to know "if the baby {was} too hot or too cold" ..to hear baby's sounds" (28).
2b) Is Moral Character A Function of The Sleep Environment?

What might come as a surprise to some researchers is the work of cultural psychologist Shweder and his colleagues at the University of Chicago (second passage). They show explicitly that concerns for "moral goods" (taken here to mean concerns or preferences for particular personal qualities or behavior and personality or character outcomes) are deeply embedded in and reflective of notions about proper sleeping arrangements, regardless of whether these notions are scientifically based or simply folk assumptions (2). Their cross-cultural comparisons reveal that in choosing sleeping arrangements parents feel a powerful concern for what "looks" morally acceptable and for practices they've come to believe lead to certain moral traits. At least initially, not only is it believed that certain "types" of sleeping arrangements produce certain "types" of children, but that they reflect certain "types" of parents (i.e. good or moral parents) who are themselves judged by family, friends and community, depending on where they place their infants or children for nighttime sleep (2, 29).

Shweder's et al showed specifically that where and with whom some American children are allowed to sleep is guided by concerns for three specific moral issues: the sacredness-separateness (from children) of the husband-wife relationship; the appearance of incest avoidance, and the importance of teaching the child self-reliance and independence by enforcing the infant /child to sleep alone.

Perhaps the overriding importance of these moral goods in certain segments of American society helps to explain why culture-based"folk" and scientific understandings of infant and childhood sleep often intermingle, and mutually reinforce each other. In pediatric sleep medicine, for example, it is often difficult to distinguish between what is passed on to parents as proven scientific findings---in relation to how sleeping arrangements affect marriages, personality development, self confidence, independence and/or overall satisfaction with life---and what is simply personal judgment on the part of the advice giver (see 18,22).
Interestingly, the "moral" outcomes parents desire to instill in their children through choices for particular sleeping arrangements contrast and often conflict with the sleep management strategies parents think they need to employ to obtain those outcomes. For example, western parents generally seek to instill sensitivity, kindness, trust and empathy in their children (30), at the same time as wanting to create separateness, self-reliance and/or autonomy through enforced solitary sleep, the latter of which can be facilitated through first withdrawing and then eliminating nighttime feeds and parental contact (26). Such emotionally conflicted parents will often display inconsistent (on-again, off-again) enforcement of solitary sleep, alternating between some form of cosleeping and separate sleeping arrangements, an important phenomenon called reactive cosleeping first introduced by Madansky and Edelbrock (31)). But reactive cosleeping only exacerbates parent-child sleep struggles, and certainly does not eliminate them, as their study illustrates (31).

2C) Do Solitary? or Social? Infant Sleeping Arrangements Produce
Independent, Satisfied, (Moral) Children and Adults? Is This The Right Question?

The absence of systematic studies on the relationship between acquired infant/child personality characteristics and routine sleeping arrangements probably explains why western conventional understandings about the relationship between solitary infant sleeping arrangements and early independence are imprecise and misleading at best. Recent systematic studies are beginning to provide evidence that contradicts conventional wisdom on solitary sleep in early childhood. Consider:

* Heron's (17) recent cross-sectional study of middle class English children shows that amongst the children who "never" slept in their parents bed there was a trend to be harder to control, less happy, exhibit a greater number of tantrums. Moreover, he found that those children who never were permitted to bedshare were actually more fearful than children who always slept in their parents bed, for all of the night (17).

* In a survey of adult college age subjects, Lewis and Janda (32) report that males who coslept with their parents between birth and five years of age had significantly higher self-esteem, experienced less guilt and anxiety, and reported greater frequency of sex. Boys who coslept between 6 and 11 years of age also had higher self-esteem. For women, cosleeping during childhood was associated with less discomfort about physical contact and affection as adults. (While these traits may be confounded by parental attitudes, such findings are clearly inconsistent with the folk belief that cosleeping has detrimental long-term effects on psycho--social development.

* Crawford (33) found that women who coslept as children had higher self esteem than those who did not. Indeed, cosleeping appears to promote confidence, self-esteem, and intimacy, possibly by reflecting an attitude of parental acceptance (Lewis and Janda 1988).

* A study of parents of 86 children in clinics of pediatrics and child psychiatry (ages 2-13 years) on military bases (offspring of military personel) revealed that cosleeping children received higher evaluations of their comportment from their teachers than did solitary sleeping children, and they were under-represented in psychiatric populations compared with children who did not cosleep. The authors state: "Contrary to expectations, those children who had not had previous professional attention for emotional or behavioral problems coslept more frequently than did children who were known to have had psychiatric intervention, and lower parental ratings of adaptive functioning. The same finding occurred in a sample of boys one might consider "Oedipal victors" (e.g. 3 year old and older boys who sleep with their mothers in the absence of their fathers)--a finding which directly opposes traditional analytic thought" (16).

* Again, in England Heron (17) found that it was the solitary sleeping children who were harder to handle (as reported by their parents) and who dealt less well with stress, and who were rated as being more (not less) dependent on their parents than were the cosleepers!

* And in the largest and possible most systematic study to date, conducted on five different ethnic groups from both Chicago and New York involving over 1,400 subjects Mosenkis (34) found far more positive adult outcomes for individuals who coslept as a child, among almost all ethnic groups (African Americans and Puerto Ricans in New York, Puerto Ricans,, Dominicans, and Mexicans in Chicago ) than there were negative findings. An especially robust finding which cut across all the ethnic groups included in the study was that cosleepers exhibited a feeling of satisfaction with life.

But Mosenkis's main finding went beyond trying to determine causal links between sleeping arrangements and adult characteristics or experiences. Perhaps his most important finding was that the interpretation of "outcome" of cosleeping had to be understood within the context specific to each cultural milieu, and within the relational matrix within which it occurs. For the most part, cosleeping as a child did not correlate with anything in any simple or direct way. He concluded that there is no one "function' of cosleeping but that cosleeping as a child interacts with a variety of cultural, social and unique developmental characteristics of the relational setting (34), and that sleeping arrangement is but a small part of a larger system affecting adult characteristics (34).

2D) Beliefs about the consequences of non-traditional sleeping arrangements: science or religion?

At least judging from public discourse, the validity of predicted outcomes associated with particular sleeping arrangements need not be demonstrated or proven scientifically, as long as people believe that they do, or that the outcomes promised reflect, compliment, or in some way support, the prevailing values and goals which justified the recommended practice in the first place. For example, in contrast with situations where parents and children sleep together (cosleep) solitary childhood sleeping arrangements are believed to foster more independent infants and children. The problem is that no study has ever defined what exactly is meant by independence, or how it should be measured or, assuming it can be measured, or, assuming it can or could be achieved at a young age, whether this quality or character is causally linked to childhood satisfaction, competence or happiness. Furthermore, no study has ever determined if the ability to sleep alone through the night at an early age relates to the emergence of other skills or personality characteristics unavailable to infants and children sleeping under different conditions.

When discussions turn to non-traditional sleeping arrangements, much is presumed but little or nothing is proven. For example, it is often implied or stated outright that cosleeping exacerbates or creates a parent-child sleep problems, but this appears to be true where parents do not value cosleeping such as when parents permit a child to sleep in their bed as a response to on-going sleep difficulties. Furthermore, Hayes et al (35) studied cosleeping among 51 3-5 years olds and found that in the subgroup that were considered difficult sleepers, all but 1 (of the 51) had developed sleep problems in the context of sleeping alone; that is, originally all the children that developed into "problem sleepers" as defined by their parents, had been placed in a separate bed from infancy. And even where cosleeping parents report problems, this does not necessarily mean that it is not still the preferred sleeping arrangement.

Whether sleeping alone or socially, the functions of the sleep environment for a child change in relationship to age (36, 37), and/or changing circumstances. For example, the physiological consequences of a mother sleeping beside her 1-month -old infant are enormously different from the physiological consequences associated with her sleeping with this same child 13 months later when cognitive and psychological systems are much more mature. At one month, and owing to the human infant's extreme neurological immaturity at birth and continuing slow development, the mother's body acts as a cue or trigger in regulating the baby's body temperature, breathing, arousal patterns, cortisol levels and sleep architecture (38-41). But at two and/or five or thirteen years of age children will actively interpret the relational meaning and affects of cosleeping with their parents while the initial important physiological effects will diminish. Indeed, whether the consequences of the sleeping arrangement is beneficial, benign or deleterious (at any given age) will depend not simply on the location, where the sleep occurs, but on the social meaning and psychological content of the relationship of the participants, as expressed within the family, of which sleeping arrangement per se is but a small reflection and part. Such critical analytic distinctions are mostly absent when the potential value of non-traditional sleeping arrangements (especially cosleeping) are addressed (42).

3. Conventional Western Understandings of "Healthy, Normal" Infant and Childhood Sleep: Where Did They Come From? Is One Form Of Sleep As Good As Any Other?

It is tempting to use the concept cultural relativism to argue that regardless of differences in the ways infants or children's sleep worldwide, each culturally-based strategy is equally valid and appropriate. Such a simplistic perspective is fallacious, however, in a number of ways. First, it presumes that parents in all societies are equally satisfied with the way their infants and children sleep, or that parents (and children) are equally well rested despite differences in how or where they sleep. Though it is hard to compare across all cultures, the impression by many anthropologists is that (in general) parents living in western industrialized societies are much less satisfied with how their children sleep than are parents in nonwestern societies, and that in industrialized societies nightly infant and childhood sleep comes about under more stressful conditions (43,44).

A second fallacy is the erroneous assumption that any society (including our own) necessarily produces a sleep management strategy that is appropriate for all, and that it is optimal (promote maximum health) for all, or is always compatible with the short or long term biological needs of the infant. Parental caregiving choices that satisfy parental best interests are not, for example, necessarily the same as those which best serve the infant's (40). And while modern lifestyles and/or technology offer some effective substitutes for parental nurturing (contact, protection and support) it is worthwhile to recall Bruner's warning that "it would be a mistake to leap to the conclusion that because human immaturity makes possible high flexibility in later adjustment, anything is possible for the species...we would err if we assumed a priori that man's inheritance places no constraint on his power to adapt (45).
A third problem with the relativist perspective is that it erroneously implies that within any given society each family's values and goals are the same, and that publicly preferred or "ideal" sleeping arrangements are those which are actually practiced. We now have evidence there is much more variability regarding sleep practices especially in the United States and the United kingdom than has ever been acknowledged (16, 46,47,48).

Obviously, each culture is unique, and there must be some compatibility between family behaviors and the society within which they live. My criticism is that the pediatric sleep community continues to make it uncomfortable for many parents to practice sleeping and nighttime feeding arrangements that differ from their own. More importantly, I regret that the "science" of infant sleep continues, for the most part, to disregard the significance of mother's presence as a biological regulator of infant sleep as it unfolds and develops within the cosleeping/breast feeding adaptive complex. I argue that this situation precludes a full understanding on infant sleep physiology and development and, therefore, a full understanding of the likely etiology of so many sleep-related problems infants, children and parents experience.

In my own work no particular sleeping arrangement is advocated to any particular family. Rather my colleagues and I advocate a perspective from which other kinds of analysis and concerns can proceed. An evolutionary perspective provides a more objective context, I believe, for understanding infant responses to the diverse sleep environments cultures provide (49-51. As a conceptual tool evolution offers a beginning point to consider how social factors come to predominate over and influence infant and childhood sleep biology and development (42). Anthropological studies which incorporate and evolutionary framework reveal that infant sleep physiology evolved in the context of continuous maternal contact including baby-controlled nighttime breast feeding (52,53). This fact permits us to argue that in order to understand specieswide infant sleep-wake patterns and/or sleep architecture infant sleep must be studied under conditions that mimic this "environment of adaptedness" (54).
In western cultures (as described above) generally clinicians continue to advocate only one form of sleep for infants and children (i.e. solitary sleep ) and sleep management strategies aimed at sharply reducing as early in life as possible parental handling and feeding of infants at bedtime. Parents are encouraged not to permit infants to associate falling asleep with food (including breast feeding) or parental touch (18, 26, 55, 56), the very context within which the infant's "falling asleep", in relationship to parental emotions evolved. Breast feeding rates arae increasing in the United States (57). If falling asleep at the breast is as common and, apparently, as biologically appropriate as cross-cultural data suggest (43), then this recommendation will prove problematic for many mothers and infants.

Given the western cultural and historical context within which infant sleep studies were begun, these contemporary recommendations are understandable. Both clinicians and pediatricians encounter parents who need simple, practical solutions to immediate, on-going problems associated with solitary infant sleep. Thus, clinicians impressions are colored by, and mostly limited to, families in crisis. They hear little testimony from parents who have found alternative sleeping arrangements (to the solitary model), and who enjoy their alternative choices. Second, infant sleep studies were first conducted by researchers in the fifties and sixties when breast feeding was at an all time low and cosleeping was regarded as being aberrant, and definitely to be avoided. Since the significance of mother-infant cosleeping with nighttime breast feeding was considered neither biologically nor culturally appropriate, it is not surprising that patterns of childhood sleep development considered clinically ""healthy" and normal" were those patterns expressed by bottle-fed infants sleeping alone in sleep laboratories.

3a) The Traditional Sleep Research Paradigm is Inadequate for the Diversity of Family Sleep Practices It Must and Should Accommodate

"It is hypothesized that the progressive organization of sleep and wakefulness at night in infancy reflects the integration of constitutional propensities of the infant (temperament) in interaction with the infants multiple contexts...Contextual relationships are mediated by the infants primary relationships which are different from, but have their origins in, the infant's social dyadic interactions (6)."

Anders (6) suggests in the quote above that patterns of "normal" and "appropriate" infant sleep development are extremely variable and responsive to a variety of environmental i.e. contextual processes. Some of these processes involve family interactional factors which characterize the nature and affectional structure of the social relationships each parent experiences with their infant or child during the day (58). If fully realized by researchers and clinicians alike the "transactional" model that Anders ( 6) and Sadeh and Anders (4 ) envision offers a revolutionary approach to studying and understanding infant sleep development, and for creating the inclusive paradigm for which this chapter argues.

Indeed, a transactional approach takes Lozoff and her colleagues one step further. The approach acknowledges at the outset that "normal" infant sleep development not only can vary within different cultural subgroups, but also from one infant to the next, depending upon the interplay of intrinsic and extrinsic variables significant to each developing child. Intrinsic factors can include, but are not limited to, infant temperament, growth rate and neurological status (constitutional needs) at birth. Extrinsic factors, with which intrinsic variables interact, can involve such things as whether infants are breast or bottle fed, (59), whether or not the infant feeds on its own or on it's parent's schedule (60), whether the infant sleeps in the same bed, same room, or different room (alone) (61, 62), whether the infant sleeps on it's back, side or belly (63), and whether the family generally favors nighttime contact or discourages or resists it (17), and whether the infant has siblings or is an only child. All of these factors (and others) can alter the trajectory of infant sleep development in important ways.

Harkness et al (64) point out that the traditional theoretical models, explanations, and clinical treatments of infants with dysommnias and parasomnias continue to be predicated on the notion that the ontogeny or maturation of infant sleep is, in the vernacular, fairly predictable, clean and neat. Changes in infant sleep architecture, particularly the reversal of the predominance of active to quiet sleep, is reported to follow an orderly, unfolding pattern dominated by endogenous mechanisms. For example, during the first year of life a more stable "adult-like" pattern of sleep emerges. The infant sleeps for longer and longer (relatively uninterrupted) periods in increasingly deeper (Delta wave) sleep which is thought to reflect an increase in the level of "integrity and maturity" of the central nervous system (64). Indeed, the ability of infants to return to sleep unassisted after awakening (to self soothe), to "sleep through the night" as early in life as possible with minimal parental contact continues to be a developmental benchmark against which infants and their caregivers are evaluated, even when "sleeping through the night" is not an important issue for the parents. Such a criteria used to evaluate "developmental progress" may do more harm than good if the sleeping arrangements actually practiced are not the same as the one for whicthe evaluation was intended.

3B) Examples of how culturally guided "choices" concerning sleeping arrangements and related sleep practices matter biologically to the infant, and change "normative" sleep development.

Infant Sleep Position and SIDS Susceptibility

Consider how sensitive the infants sleep behavior, physiology and health is to culturally guided decisions about how, where, with whom (if anyone) infants should sleep. Indeed, while Lozoff and her colleagues hinted at it, they never could have predicted the degree to which culturally-based decisions regarding infant and childhood sleep affects development and nightly sleep physiology, including the chances of an infant dying from the sudden infant death syndrome (SIDS). In fact, the sleeping position of the infant has proven to be the single most important factor for reducing the chances of an infant dying of SIDS (65), although the reasons for increased risk remain unknown. The discovery that, merely by placing infants in the supine, rather than in the prone sleep position SIDS rates could decline as much as 90% in some countries continues to astonish many SIDS researchers worldwide (66). The decision to recommend the dangerous prone sleeping position emerged from the widely accepted belief that if prone sleeping helped premature infants to breathe and sleep better than it could probably do the same for older- term infants. The possibility that supine infant sleep could make the infant vulnerable to choking (esophageal reflux ) only added to the resolve of physicians to lay infants prone for sleep (67).

Do infantile arousal mechanisms needed to protect infants during respiratory crises follow the same time course of development as the neurological mechanisms that promote longer periods of deeper sleep (delta wave, stage 3 and 4)? This is an important question, as pertains susceptibility to SIDS (68). Over twenty years ago Douthitt and Brackbill (69) found that prone sleeping newborns slept longer and deeper (aroused less and slept longer) than did supine sleeping infants. That is, infants sleeping on their backs experienced twice as many motor activities during sleep and more awakenings than did prone sleeping newborns, findings recently confirmed by Kahn et al (70). Since the goal of both parents and health professionals in western societies was and continues to be to promote sleep, and not awakenings, it is easy to understand why these earlier data provided evidence for why infants should be placed in the prone position. Yet, it has been suggested that some infants who die of SIDS perhaps cannot arouse or awaken easily or fast enough to terminate a cardio-respiratory crisis during sleep, especially while in deep sleep where arousal thresholds are higher (68 ). These findings raise the possibility that the supine sleep might well be safer precisely because of the increased arousal and motor activity which accompanies it. even though the implications of this possibility conflicts with cultural strategies to promote early "deep" sleep in infants as early in life as possible.

Thre are other parent-controlled "social" precautions that lower the risks of SIDS. Mitchell (71) found that the presence of a responsible adult sleeping in the same room as an infant reduced by four -fold the chances of infants dying from SIDS. This protective effect did not generalize to cosleeping among siblings indicating that a responsible role played by the caregiver is likely critical in reducing the chances of the infant dying. Moreover, the largest epidemiological study to date conducted in Great Britain also shows increased risks for infants sleeping in rooms alone, as well as for babies sleeping in their mother's beds, if the mother smokes. Other dangerous conditions include the use of duvets pulled up over the infants head, and the use of soft mattresses. Overheating by over-wrapping an infant also significantly increased SIDS risks, All of these new data illustrate the extent to which infant sleep physiology is directly mediated by parental intervention (see Fleming, this volume).

Feeding Practices

Bottle-fed infants exhibit significantly different nightly sleep profiles than do breast fed infants. And infants breast fed for a year or more, develop different sleep patterns than do infants breast fed for only the first three months (15). Recall that Oberlander et al (72) found that among newborns a complete milk formula feed increased post-feed sleep by 46% and 118%, compared to water or carbohydrate-only feedings. Furthermore, the most recent Ross surveys indicate that 62% of contemporary mothers in the United States are breast feeding when they leave the hospital (57) And new evidence suggests that at least among Latinos mothers continue to provide their infants with at least two breast feeds or more from midnight through to the morning (59).

That so many more mothers are now breast feeding their infants for increasingly longer periods makes sleep models based only on data from infants fed artificial or cows milk (from bottles) highly problematic for at least half of the population of contemporary American infants. And while breast feeding drops to 26% at six months the number of mothers breast feeding is continuing to rise in the United States (59). This is particularly significant since, as described below, in addition to sleep differences induced by breast vs. cows milk, sleep proximity to mother also influences the frequency and duration of feeding bouts.(59). Maternal proximity in the form of bedsharing, in addition to breast feeding, especially changes the infant's nightly sleep architecture including arousals and sleep period time. Developmental models of infant sleep in the first year of life that do not consider feeding method and frequency in relationship to sleeping arrangements, are not therefore appropriate for many infants.

Over twenty years ago Harper et al (73) argued that feeding behavior asserts an underestimated role in regulating infant sleep physiology and sleep architecture, even though most pediatric sleep research papers rarely include data on feeding method and frequency. For example, he and his colleagues found that among bottle fed, solitary sleeping infants the waking periods associated with feeding increased the probability of a subsequent REM period, a finding consistent with previous work on small mammals. They suggested that because REM sleep and quiet sleep followed each other in sequential fashion a change in the relative distribution of REM sleep altered the likely sequence of state. Their laboratory research on bottle fed infants showed that feeding tended to entrain the subsequent REM-QS cycle in that the percentage of REM increased after feeding and then dropped sharply approximately 20 minutes later, with a corresponding increase in quiet sleep. They concluded that "... the interpretation of behavior resulting from maternal-infant interaction should be viewed within the framework of incorporation of food, in that satiety play a large role in regulation of state integration and cardiac response" (73).

"Choice" of sleeping arrangement was found to greatly increase not only the number of breast feeds, but the total nightly durations of breast feeding and the average intervals between the feeding sessions. For example, amongst 70 nearly exclusively breast feeding Latina mothers and their 2-4 month old infants, we found that when bedsharing the average interval between the breast feeds was approximately an hour and a half, but when sleeping apart in separate bedrooms (but still within earshot) the interval was at least twice as long (about three hours). Moreover, on their bedsharing nights we reported that babies breast fed twice as often for three times the total nightly duration than they did when they slept alone (59).
These differences in feeding were part of a broader complex of differences, a cascade of interconnected changes induced by the presence of the mother. Sleeping together altered not only feeding behavior within what was supposed to be a homogenous breast feeding group, but also infant and maternal arousal patterns (75), and sleep architecture (61 and below) mother-baby body orientations in bed (77), infant respiratory behavior (78) and almost every major parameter important in understanding infant and maternal sleep physiology (see Figure 1 and 2 and discussion below).

Infant and Maternal Arousals, Temporal Correspondences, and Sleep Architecture, Among Solitary and Bedsharing Mother-Baby Pairs

"Separate normative values for infant sleep need to be developed for infants who bedshare, and existing norms should be reinterpreted within the cultural context in which they were established" (61).

In three, in-house laboratory studies of one form of mother-infant cosleeping, bedsharing, we used standardized polysomnography and infra red photography. We quantified differences in the behavior and physiology of mother-infant pairs as they shared a bed or slept apart. The data show that while bedsharing a significant amount of temporal correspondence occurred between the sleeping pair's transient (brief) arousals, and between their larger epochal awakenings (75). We also found that bedsharing mother-infant pairs exhibited a trend toward greater simultaneous overlap in all sleep stages (i.e., stages 1-2, 3-4, and REM). This synchronization of sleep states was not explained by chance and is not found when the sleep/ wake activity of infants is compared to randomly selected mothers with whom they did not co-sleep (50, 79).

In our most extensive study we reported that in general small EEG defined transient infant arousals are facilitated in the bedsharing environment, selectively, and even when routinely bedsharing infants slept alone they continued to exhibit more transient arousals than do routinely solitary sleeping infants, sleeping alone ( 75). Furthermore, bedsharing significantly shortened the amount of time per episode infants remained in deeper stages of sleep (stage 3-4) compared with when they slept alone, with increases in the amount of time spent in Stage 1 and 2, and more total time asleep (61), since among other things, infants cried significantly less while sleeping with their mothers, compared with when they slept apart (51).
We also documented an acute sensitivity on the part of the routine bedsharing mothers to their infants presence in the bed. That is, compared to the number of overlapping arousals (in which the infant aroused first), routinely solitary sleeping mothers on their bedsharing night in the laboratory exhibited significantly less overlapping arousals than the routinely bedsharing mothers did indicating that bedsharing mothers do not habituate to the presence of their babies but become more sensitized to their behavior (75).

And while routinely bedsharing mother aroused and fed their infants more frequently while sleeping next to them, on average they received as much sleep as solitary breast feeding mothers, and routinely bedsharing mothers evaluated their bedsharing sleep experiences (in the laboratory) at least as positively as did routinely solitary sleeping mothers following the night when they slept in their routine (solitary) condition (76).

Altogether, these documented differences between the bedsharing and solitary sleep environments suggest the possibility that the presence or absence of the mother routinely in bed with the infant, should lead to significant changes in sleep development over the infant's first year of life--- a "normative" trajectory of sleep development not represented by the traditional paradigm.

Culture (Vis a Vis Sleeping Arrangements) Regulates Infant Breathing?

In this same study, Richard et al (78) showed that the decision to sleep with an infant in the same bed, or to place it in a separate room for sleep, contributes to differences in the infant's nightly breathing patterns. For example, the bedsharing environment is associated with more central apneas, fewer obstructive apneas, and more periodic breathing in infants than the solitary environment. During bedsharing, irrespective of the routine sleeping arrangement at home, the infant experiences a higher frequency of central apneas during stages 1-2 and REM (and overall). Among routinely solitary sleeping infants, who slept with their mothers in the same bed in the laboratory, this increase largely reflected an increase in the shortest apneas (3-5.9 sec) while in stage 1-2; in routinely bedsharing infants, it reflected increases in apneas in the 6-8.9 second range during REM, and in the apnea range of 9-11.9 seconds during stage 1-2. In contrast to central apneas, however, obstructive apneas were decreased by bedsharing, but only among routinely solitary sleeping infants (while bedsharing) who had a lower frequency overall and specifically in stages 1-2 and REM (78).
The amount of periodic breathing was also significantly increased in the bedsharing environment. Routinely bedsharing infants had a higher frequency of periodic breathing and a longer mean duration over the entire night (overall) while bedsharing, and specifically during REM. Routinely solitary sleeping infants exhibited more frequent periodic breathing only during stages 3-4, while bedsharing in the laboratory with their mothers (78).

Social Determinants of Total Infant Sleep Time And Average Bout Lengths

The ethnographic studies of infant sleep in diverse settings confirm just how extensively the infant's endogenous mechanisms transact with parental behavior. Outside of the laboratory it is clear that the total amount of daily sleep an infant experiences is regulated by the environment, and cannot be considered dependent on endogenous factors at all. For example, in a recent in-home longitudinal study, Harkness, et al (64) compared 36 American families from Cambridge, Massachusetts. The children ranged in age from birth to 36 months and were studied for over a year. Sleep behavior of the children was compared to a Dutch sample of 66 families with children (living near Leiden and Amsterdam) from different age groups ranging from 6 months to 8 years. Analysis was based on diaries kept by parents in both settings. They found that, on average, Dutch babies slept two hours longer (15 vs. 13 hours) than American infants, and the parent infant sleep "struggles" ubiquitous among the Americans was not as familiar to the Dutch (64).

The authors explained these differences between the American and Dutch infants' sleep behavior in terms of the importance of the "three R's" of Dutch childrearing: rust (rest), regelmaat (regulation) and rein held (cleanliness). The R's represent the complex of social values that underlie and validate the preferred context of solitary and prolonged infant sleep behavior. Harkness et al. (64) describe how Dutch parents bring to their child rearing an "ethnohistory" or set of beliefs, which explain why infants need a great deal of sleep and must not be over stimulated neither during the day nor night. Not only are babies put down to sleep earlier in the evenings, but rather than worrying about whether their infants are receiving enough intellectual stimulation during the day ---as American parents do ---- Dutch parents are concerned that they may be receiving too much stimulation, potentially threatening the infant's ability to sleep at night (64.).

In another study, Elias et al. (15) compared the development of sleep in infants of "standard-care" mothers (those following Dr. Spock's recommendations to minimize contact and feeding during the night), with the sleep of infants whose mothers practice care recommended by La Leche League, a worldwide health profession committed to promoting prolonged breastfeeding, physical contact, and cosleeping. Among infants receiving standard, minimal, nighttime contact care, the maximum sleep bout length increased from an average of 6.5 hours at 2 months of age to 8 hours at 4 months and to greater than 8 hours during the second year. Infants of La Leche League mothers at 2 months of age slept an average of 5 hours during their longest sleep bout. Not until they were 20 months old did these infants sleep significantly longer than 5 hours during their longest sleep bout. In contrast to the consolidated sleep of the standard-care infants, their sleep was characterized by shorter bouts and frequent awakenings at night.

In addition to bout length, total sleep time developed differently for cosleepers. La Leche League infants slept a total of 15 hours at 2 months, 12.5 hours at 4 months, and just over 11 hours by 2 years. Standard -care infants continued to sleep 13 to 14 hours per day throughout the two-year monitoring period (15). As such, Elias et al. concluded that weaning status and bed sharing have major effects on the development of sleep patterns. Indeed, in their sample these two factors explained 67 percent of the variance in bout length (see also 80, 81).

These data are consistent with babies born to mothers from a very different society but whose patterns of nighttime sleep and feeding were approximately the same as infants whose mothers practiced La Leche League recommended baby care. For example, for the first year of life and more Super and Harkness (43) documented significant nighttime infant sleep behavior differences between the Kipsigis people of rural Kenya and infants living in Los Angeles. Ten Kipsigis infants were observed over a 24 hour cycle on a series of days during the first eight months of life with records kept on their sleep-wake state and feeding patterns, while comparison data for the Los Angeles sample was provided by work conducted by Parmelee, Wenner and Schultz (82). Kipsigis babies breast feed throughout the night in close contact with their mothers in one room dwellings while American babies slept either in their own rooms or own beds. Whereas the American babies averaged 8 hours of nighttime sleep by 16 weeks of age, the Kipsigis babies continued to wake at intervals of three to four hours up to 8 months of age, the oldest age for which we kept data. They also found that over the 24 hour cycle by the 3rd and 4th month of age American babies were sleeping about 2 hours longer (43).

Thumbsucking, and Transitional Objects

Winnicott (83) first described the use of "sleep aids" by young children as part of the process by which they learn to sleep alone. In the absence of a parent or attachment figure, a young child might adopt a "special object" (blanket, favored toy, or stuffed animal) to which they attribute special qualities. These objects serve to comfort a young child during awakenings or while falling asleep (4). In western cultures transitional objects are so ubiquitous that current psychological models of development imply that their use is a natural stage through which all children pass. Use of such objects, however, is not universal, but again dependent upon the social context within which a child's nightly sleep experience begins and ends. As discussed in their review, Wolf and Lozoff (84) report that American toddlers (mean age 21.7 months) who had an adult present when they fell asleep were significantly less likely to use an attachment object (such as a blanket or doll) or to suck their thumbs, practices that appear to provide a sense of security in the absence of parental contact.

In Japan and Korea, where cosleeping is the norm, as a general rule children do not suck their thumbs at night or use transitional objects. One of the most convincing arguments that thumbsucking may well reflect the results of solitariness in young children comes from a study conducted among Turkish children, 96% of whom were thumbsuckers between the ages of 1 and 7 years. These children had been left alone as infants to fall asleep, while all of the children on the non-thumbsucking group (the majority of the total sample) had some type of adult contact or body contact, such as either being held or breastfed while falling asleep( in infancy). Even in American samples, children whose parents stayed with them at bedtime were less likely to suck their thumbs than were children who fell asleep alone (85, 86, cited in 84).

Among contemporary Mayan children, on only a rare occasion were objects used to ease the transition to sleep and there were no preparations for bed time or bed time rituals, including special nighttime clothes. Babies mostly fell asleep in their mothers arms or were breast fed to sleep, and only one child observed by Morelli et al (24) used a security (transitional) object while falling asleep. As they explain, among the Mayans infant sleep occurred in the same company with whom the babies spend their days and "no coaxing of any type is was needed to get the infant to sleep" (24).

In sum, culture (including medical views )guide parental decisions regarding infant sleep position, feeding method and distribution , whether the baby sleeps alone or with it's mother, and parental notions concerning infant vulnerabilities. In turn, parental decisions influence infant sleep behavior and physiology. This includes: infant sleep architecture, arousals, sensitivity to the presence of the mother, breathing, amount of feeding, amount of sleep, nightly infant crying time, as well as thumbsucking and the use of transitional objects. These documented, interrelated effects support Ander's (6)"transactional model" which sees the emergence of infant sleep patterns in terms of a "transaction" between extrinsic and intrinsic factors. He hypothesizes that: "the progressive organization of sleep and wakefulness at night in infancy reflects the integration of constitutional propensities of the infant (temperament) in interaction with the infant's multiple contexts....Contextual influences are mediated by the infant's primary relationships, which are different from, but have their origins in, the infant's social dyadic interactions".


Does Solitary Infant Sleep And Rigid Parental Expectations Contribute To Infant-Parent Sleep Difficulties?

That infant sleep biology changes much more slowly than do the cultural values that underlie and regulate them raise the possibility that sleep environments optimal for infants may not be the ones encouraged by the culture within which an infant's family lives. And, of course, it is highly likely that widely accepted infant sleep management strategies are sufficient for some infants and children, but unsuitable for others who vary emotionally or psychologically. Moreover, some families may apply widely accepted developmental sleep norms established for one kind of sleep environment to their own when it is inappropriate to do so,. This can have the effect of disappointing parents leading them to conclude either that their parenting skills are deficient, or that their infant or child is uncooperative. Ironically, this situation best describes what occurs in developed countries, the United States, Great Britain, and Australia where 35%, possibly as many as one out of every three otherwise healthy children have problems falling or staying asleep, after having first been conditioned to sleep alone (17, 35, 87). Such high percentages probably do not reflect infant or caregiver deficiencies, but perhaps over confidence in the validity of our definitions and expectations about how infants should sleep, and perhaps the rigidity by which parents hear, interpret and apply the message offered by health professionals.

Indeed, the rigidity by which parents are socialized to hold on to these expectations concerning how their infants should sleep can be used to predict the relative likelihood that infant-child sleep problems will manifest themselves. The more rigid parental expectations, the more likely parents report dissatisfaction with their child's sleep behavior (17, 80). And as Anders and Taylor (8, and also 4,5) ) astutely point out, night awakenings constitute a problem for only those parents who expect their children to sleep through the night at very definite ages.

Only in the last hundred years or so, in a relatively small number of world cultures, have parents and health professionals become concerned with how infants should be conditioned to sleep. And only in western cultures are infants thought to need to "learn" to sleep, in this case, alone and without parental contact. Most cultures simply take infant sleep for granted. Consider this remarkable insight offered by Harkness et al: "...in the sense that normal children everywhere will eventually sleep throughout the night, will need less sleep as they get older and will go to bed and get up at approximately the same hours as other members of the family, and they will eventually fall asleep (and wake up) without immediate support from their mothers or fathers, all four of the major behavioral stages or components of infant sleep are 'developmentally based' (64)

4) Infant-Parent or Child Cosleeping: "The Political Third Rail"? Why So Controversial?

"...Although taking your child into bed with you for a night or two may be reasonable if he is ill or very upset about something, for the most part this is not a good idea" (26).

"...The parents have to be firm and committed to returning the child to bed..parents have to learn to ignore crying until the child falls asleep. Sometimes children can cry for a couple of hours..Children may vomit with crying and so parents need to be prepared to go in to clean up the child and change the bedclothes quickly and, with the minimum of fuss, put the child back to bed, and walk out." (56).

"...sleeping in your bed can make your child feel confused and anxious rather than relaxed and reassured. Even a young toddler may find this repeated experience overly stimulating.(26).

"...advise against cosleeping may be overly simplistic" (88)

Infant-parent cosleeping is a generic concept referring to the diverse ways in which a primary (responsible) caregiver usually the mother sleeps within close proximity (arms reach) of the infant or child. This permits each to detect and respond to a variety of each other's sensory stimuli (sound, movement, smells, sights, touch). Cosleeping represents the universal (species-specific) evolved context of human infant sleep development. The breast feeding /mother-infant cosleeping arrangement is for the majority of contemporary people inevitable and inseparable, it is not a choice. This fact suggests that any universal biological understanding of infant sleep physiology and sleep-related difficulties which neglects the evolved connections between nighttime mother-infant proximity, breast feeding and infant neurological status including emotional needs, must be regarded as inaccurate, incomplete and/or fundamentally flawed.

Bedsharing is but one form of cosleeping. Others are: futon cosleeping, or infants sleeping alongside but not on the same surface as the mother. This occurs, for instance, when infants sleep in a basket or in a hammock above or on the side of the mother, or when mothers and infants lie beside each other on a mat on the floor. There can be no one outcome associated with cosleeping--benign, beneficial, or deleterious--- just as there can be no one outcome associated with solitary infant sleeping arrangements. Physiological or psychological outcomes depend on the infants or child's age, as well as on the nature of the relational setting and social conditions and physical circumstances within which cosleeping occurs.

4a How cultural/scientific bias manifests itself against the choice to "cosleep": a social critique

The idea of parent-infant cosleeping as a legitimate and appropriate choice for parents remains controversial in western societies probably because so many putative negative consequences are associated with it. These consequences are rarely contextualized or systematically documented, however. In popular parenting books, childcare bulletins and childcare magazines cosleeping can be : 1) mostly described as if it were a unitary concept; 2) ignored completely; 3) presented to parents in terms of the likely or inevitable "problems" that will, might, or could, arise if it were practiced. Sometimes it is explicitly discouraged (26), other times the message is similar but more subtle (18). The usual reasons that separate sleeping quarters for parents and children are recommended over cosleeping include: marriages might best be nurtured and preserved; infant/child individualism and autonomy promoted; incest and suffocation avoided, social (childhood) competence maximized; gender and sexual identities strengthened; and life satisfaction (for all family members) potentially realized (47, 29).

Indeed, where a "problem" or potential problem with cosleeping can be identified, rather than being considered simply a "problem to be solved" the putative problem becomes the argument against the practice, as if all families who cosleep will experience the same "problem". Furthermore, possible problems associated with cosleeping are presented as if they cannot be solved in the same manner as, for example, problems associated with solitary sleep can be solved. Throughout the literature, cosleeping is described as the cause of marital discord (58), though recent data from Sweden refutes this notion, (89), or the cause of sibling jealousies...which, while possible, may be only one of many causes of sibling jealousy! Moreover, without considering whether the particular parents involved consider cosleeping a "bad" habit or a "good" habit, parents are warned that cosleeping creates a "bad habit", one that's "difficult to break." Furthermore, cosleeping is said to "confuse" the infant or child emotionally or sexually, or to induce "over" stimulation. But no evidence is offered which specificies how, when, and under what circumstances (26). A child needs to sleep alone, it is also said (26) in order to create a sense of self, and comfort with aloneness, or skills which presumably foster self-reliance--all "moral goods", after Shweder. Again, no specifics are given, however, as to how this arrangement, only, produces these outcomes, leaving the readers to assume that solitary sleep is the only way.

Certainly, concerns for infant safety top the list of reasons why some health professionals suggest that all cosleeping should be avoided. And it is true that modern beds were not designed for infant safety. Suffocation and the sudden infant death syndrome (SIDS) which are mostly indistinguishable from each other are argued to be two potential consequences of parents-infant cosleeping (71). Indeed, where mattresses are soft, the mother smokes and/or any adult cosleeper is desensitized by drugs, bedsharing should definitely be avoided--and there are many other conditions which would make bedsharing less than an ideal choice, including the parents discomfort with the idea. But recognizing when and where cosleeping in the form of bedsharing should be avoided is different than assuming that all bedsharing is dangerous--as laboratory (49, 59, 61, 75.76, 90, 91), home (46), and epidemiological studies of unexpected deaths in infants (see Fleming et al and this volume ) are making clear.
Cosleeping /bedsharing is not synonymous with dangerous sleep environments, although dangerous conditions are used inappropriately as a proxy for the act itself i.e.mothers and infants lying side by side), as current debates about cosleeping are beginning to reveal (92,93.) The exaggerated fear of suffocating an infant while cosleeping may, in part, stem from western cultural history. During the last 500 years many economically destitute women living in Paris, Brussels, Munich and London (to name but a few locales) confessed to Catholic priests of having murdered by overlaying their infants, in order to control family size (94.95, 96). Led by the priests who threatened ex-communication, fines or imprisonment (for actual deaths) infants were banned from parental beds. The legacy of this particular historical condition in western history probably converged with other changing social mores and customs (values favoring privacy, self-reliance, individualism) providing a philisophical foundation for contemporary cultural beliefs. This fondation makes it far easier to find dangers associated with cosleeping than to find (or assume) hidden benefits.
The proliferation and expansion of the idea of "romantic love" throughout Europe, coupled with the belief in the importance of the "conjugal" (husband-wife) relationship probably also promoted separate sleeping quarters. This physical separation, especially of the father from his children, maximized his ability to dispense religious training and to display moral authority, it has been proposed (96, 97).

Like many relational issues, parent-child cosleeping may require unique solutions to assure, in this case, safety and "private adult time. However, that "problems" in need of solving can be associated with cosleeping is no more an argument against it's legitimacy, than is the fact that thousands of parents purchase books to solve the "problems" associated with solitary infant sleep.

As Kuhn (98) noted, scientific paradigms change neither quickly nor easily. The controversy surrounding cosleeping and the value of mother-infant cosleeping studies might partially be explained by these topics being part of a new paradigm that is not readily or necessarily easily assimilated by those who have worked all of their scientific lives documenting the normality of solitary infant sleep, and accepting uncritically the alleged deleterious consequences of infant-parent cosleeping. Researchers, clinicians and parents alike share many common cultural experiences . This common background probably means that most or very few of them routinely coslept with their own parents, which strongly influences ones comfort with the practice (99). Perhaps an appreciation of diverse childcare practices including cosleeping will come only when non-European immigrants come to dominate Western countries. As demographics on that score suggest, the question is not if the paradigm will change, but how soon.

4b) Cosleeping/ Bedsharing in Western Societies: How Often? How Much of the Night? Who Really Knows?

Infant-parent cosleeping represents the universal, species-wide pattern of sleep for children worldwide. Barry and Paxson (10) surveyed the sleeping practices of 186 independent societies in a sample representative of all known major cultural types in the world. Of the 119 cultures with reliable ethnographic data on parental nighttime sleeping proximity to infants, mothers slept in the same bed with their infants in 76 cultures (64%). In 20% of these cases, the father slept in the same bed as well. In none of the cultures was the infant actually isolated at bedtime. Always the baby was placed in sensory proximity of another person, but not necessarily sleep on the same surface.

Few studies have addressed the prevalence of parent-infant cosleeping in the United States and most surveys are now dated. It is a difficult subject on which to collect accurate information. Some American subgroups are comfortable reporting that they cosleep while others are not. Fear of censure and/or parental perceptions that bedsharing is outside of the cultural norm probably leads to underreporting (58, 99,100). Until recently, popular parenting books and magazines warned parents about the psychological consequences of colseeping. That parents might fear disapproval and be reluctant to admit to cosleeping is justified. One survey in 1984 found that 94% of pediatricians disapproved of cosleeping. Although that number is likely considerable lower today negative opinions about cosleeping probably remain high (88).

That said, even within western industrialized cultures it appears that diverse forms cosleeping is not uncommon. For example, Abbott (29) found that in Eastern Kentucky (Appalachia) infant-parent cosleeping is prevalent among white Americans who seem not "...to care what doctors say" believing rather that " it is best for the mother and child to be together..." Says another informant, "These new mothers are losing two of the greatest blessings that God gave mothers: the pleasure of sleeping with your child and letting it nurse" (29). Abbot argues that Eastern Kentucky practice of parents sleeping with or near their infants throughout the first two years of life is a strategy used by parents in this subgroup to induce interdependence, which is preferred to independence. As one Eastern Kentucky woman phrased it :...how can you expect to hold on to them later in life if you begin their lives by pushing them away" (29).
In the well-cited study conducted of parent-infant cosleeping among urban Americans in Cleveland , Lozoff et al. (88) found that 35% of poor urban whites and 79% of poor urban blacks routinely slept with their children, who ranged in age from 6 months to 4 years. In contrast, Anders and Keener (36) recorded the nighttime sleep of forty newborns and found that between the time the infant was initially laid in the crib and the time it was removed in the morning, at 2 and 4 weeks of life, the infant spent less than 20 percent of the night outside of the crib. After the age of 20 weeks (5 months) through to the first birthday, infants spent less than 3% of the night outside their cribs.

Of the 150 mothers in the Cleveland area 71% of the mothers indicated that they did not practice co-sleeping during the month before the interview, and 65% disclosed that they did not provide any body contact to their child at bedtime (88). However, what parents say and what they actually do are often two different things. For example, in this same survey fewer than 35% of these mothers indicated that they were "firm" in adhering to these stated practices when their child continued to awaken during the night, was ill, or was frightened.
In the Boston metropolitan area (Worcester) Madansky and Edelbrock (31)found similar differences between black and white families. The majority of parents in the sample, 55% reported that their 2- to 3- year olds had slept in their bed at least once in the last 2 months, and 14 % reported co-sleeping several times a week. Seventy-six percent of the black families co-slept while 53% of the white families did. Black families were more than twice as likely as whites to co-sleep more than twice a week (50% to 21% respectively).
A relatively recent study of cosleeping in Harlem by Schacter-Fuchs et.al. (48) reveals that 20% of Hispanic Americans slept with their children all night at least three nights a week, compared with only 6% of the white families sampled there.

Among US La Leche League mothers, a worldwide organization committed to promoting frequent nursing, late weaning, and close parent-infant physical contact, mothers frequently share a bed with their infants and children. Elias et.al. (15 )showed that between 2 to 13 months of age, 60-90% of La Leche League infants slept with their mothers. Especially for upper middle class families nighttime nurturing in the form of cosleeping is one way that mothers and fathers feel they can compensate for time spent apart from children during the day. Says one career woman interviewed in Southern California: " Sleeping with my baby lets me make up some time I couldn't spend with her during the day, since my husband and I do not return to the house until early evening. Cosleeping gives me more time to feel and nurture my baby".

Among middle to upper class (Caucasian) families cosleeping no longer appears to be taboo as it was just a decade ago, (46). The fact that over half of all American mothers are breast feeding for between 3 and 6 months or longer (57) make it even more likely that increasing numbers of mothers are sleeping with or near their infants or children to facilitate nighttime feeds. Breast feeding promotes bedsharing (100). Still, fear of censure by pediatricians, family and friends prevent many parents from discussing their nighttime caregiving practices if they happen to vary from the expected "norms" (88, 99, 101).

4c) Closet Cosleepers, Changing Demographics of Cosleeping Families and Dear Abby?

That many more parents sleep with their infants or children in western societies than is ever reported is further indicated by recent anthropological field studies in Great Britain. Ball and Hooker (46) studied a white working class community in northeast England. They found that parents often respond to questions regarding the place where the infant sleeps at night by identifying the place where the infant starts the night, or where the infant "is supposed to sleep" but not necessarily with where the infant spends most of the night!

Ball and Hooker filmed nighttime parenting behavior using infra red cameras placed in the parents' bedroom. In addition, they conducted two sets of interviews-- one before the infant was born, the other when the infant was 2 months old. Their study revealed that unless researchers specifically asked parents if the babies were moved during the night possibly as many as half the infants would not have been identified as cosleepers (46), who actually were.
Attitudes regarding the validity of the choice to "cosleep" are changing in western countries. Perhaps advice columnist Abigail van Buren (Dear Abby) reflects where popular culture is headed on this issue. Recently a "Dear Abby" letter published in the Chicago Tribune was received from a husband who signed his letter: "Crowded Bed". He complained to Abby about his wife's insistence that their 16 month old daughter be permitted to sleep in their bed and he asked for Abby's opinion. She responded with: "Dear Crowded Bed: In some cultures it is normal for a baby to share the parents bed until mid-childhood. .An infant will adjust to the style parents choose...but Alicia can learn to sleep comfortable in her own bed, if that is what you choose to teach her (102).

5. Conclusions/ Recommendations/ Afterthoughts

"People order their universe through social bias. By bringing these biases out in the open, we will understand better which policy issues can be reconciled and which cannot"(103).

Lozoff and her colleagues were right. Culture and medical practice affect each other in powerful ways. I like to keep in mind that cultural biases in science do not invalidate or make any less important the methods or insights that science provides (to change Lozoff's phrasing just a bit). Biases do, however, require scientists to constantly rethink what questions are asked, which are ignored, and why. This reconsideration must include examining what cultural assumptions underlie, direct and ultimately limit the interpretation of data. That scientists strive to be objective cannot, of course, ameliorate intellectual prejudice.
This essay revisits insights offered over a decade ago. Lozoff and her colleagues (1) suggested that it is important to be conscious of Euroamerican biases regarding "proper" childhood sleep habits that find expression in the pediatricians office. This chapter builds on their work. I call attention to the way specific ideologies continue to effect and constrain pediatric and clinical sleep practice and research. By broadening working models of childhood sleep, and encouraging the use of a more diverse range of concepts to be used by parents, researchers and clinicians, I suggest that we have a better chance of finding a better fit between family characteristics, sleeping arrangements, and the needs of particular infants, children and parents.

This critique is not meant to malign any of my colleagues whose work makes my own possible. I am aware that my own training and research experiences (in anthropology) lead to yet another type of bias. But this is precisely why the intersection of different perspectives and dsiciplines is so critical. Not only are unstated assumptions in each area of inquiry made explicit, but we are made aware that discipline biases shape and limit research. Surely, all of this means simpy that no one discipline can do it all.

Along these lines many different ideas and issues are proposed in this chapter. Perhaps the most important are:

1) In pediatric practice physicians should be prepared to give advice relevant to culturally diverse parental childcare goals, attitudes, desires and approaches , and attempts should be made to inform parents about a broad range of sleeping and feeding patterns, which means discussing choices that might differ from those chosen by the physician. The potential advantages and disadvantages of all sleeping arrangements should be raised, and mention of safety precautions for all choices should be included in discussions;

2) Problems associated with non-traditional sleeping arrangements, such as cosleeping, do not by themselves constitute arguments against the validity of the choice. Nor do the existence of "problems" suggest that they cannot be solved, or that particular problems are intrinsic to the practice and inevitable;

3) The human infant's extreme neurological immaturity at birth makes social care (including sleeping arrangements of young infants) practically synonymous with physiological regulation. This is an extraordinarily important and unique aspect of the importance of the sleep environment for the human infant--a significance that is not acknowledged by the traditional paradigm or, in general, by pediatricians and sleep clinicians;

4) Unless it is determined that mothers want to reduce nighttime breast feeding, it should not automatically be assumed by sleep clinicians or pediatricians that the best approach is: the fewer feeds, the earlier in life, the better. The benefits of breast milk including nighttime breast feeds are far too significant, as recent scientific studies have revealed. The choice belongs to fully informed parents, not to advice givers;

5) Regardless of where parents want their children to sleep, as a beginning point for understanding, parents should be reminded that, biologically and psychologically, infants, children and their parents are designed to sleep close. It is perfectly appropriate that some parents, perhaps many, may choose not to do so. However,it should be explained to parents that the infant's inability to "sleep through the night" or to sleep alone easily, should not be interpreted as a deficiency or as manipulation on th epart of the infant. Such an understandings may help prevent parents from evaluating their own caregiving skills negatively and/or their infants or children's behavior as abnormal, bizarre or deficient;

6) A more scientifically accurate, or "user-friendly" approach to infant-childhood sleep problems and potential solutions requires sensitivity to the legitimacy of diverse choices parents might make. The transactional model described by Anders (6) and Sadeh and Anders (4, 5) can guide both research and clinical practice into the new millennia. They describe a model that can accommodate biological as well as socio-cultural and psychological influences on sleep development.--and, indeed, it is a model which sees these factors as being inseparable. This model can help researchers to formulate new questions, further demonstrating how culturally guided choices influence infant sleep and potentially induce significant physiological regulatory effects --some of which can be life saving, as discussed.

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