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Sleep

and Bedtime

Behavior

in

Preschool-Aged

Children

Antonio U. Beltramini, MD, and Margaret E. Hertzig, MD

From the Department of Psychiatry, Cornell University Medical College, New York

ABSTRACT. Age stage-specific changes in patterns of

sleep and bedtime behavior were examined in 109

nor-mally developing preschool-aged children who were the

subjects of the New York Longitudinal Study of

Temper-ament and Development. The data were derived from

information abstracted from interviews conducted with

parents about the behavior of their children in daily life

situations at 1, 2, 3, 4, and 5 years of age. The following

age trends were found: older children were significantly

more likely to exhibit a prolongation of bedtime routine,

insist on sleeping with the light on, take a treasured object to bed, request parental attention after being told

good night, and experience delays in falling asleep than

were younger children. The frequency of occurrence of

night awakening was not different at the different age

levels examined, although older children were signif-icantly more likely to experience nightmares. The fathers

of older children were significantly more likely to

partic-ipate in bedtime routines, and older children were also

significantly more likely to share a bedroom with a sibling.

No sex differences were found. Pediatrics

1983;71:153.-158; sleep, bedtime, development, preschool.

The present report is concerned with the

exami-nation of age stage-specific changes in patterns of sleep and bedtime behavior in normally developing

preschool-aged children who were the subjects of

the New York Longitudinal Study of Temperament

and Development.”2 Interest in this question

de-rives from the fact that the establishment and

main-tenance of stable patterns of nighttime sleep is of

major importance to both the developing child and

his or her caretakers. For the child, adequate sleep

at night is an essential precondition for maximal

daytime alertness and responsivity to social

inter-actions and other environmental stimuli and events.

In addition, prolonged delays in falling asleep and/ or frequent night awakening may be poorly toler-ated by many parents and disruptive to their func-tioning both within and outside the family setting. Moreover, pediatricians and family practitioners are frequently consulted when a child’s behavior at bedtime or during the night is defined as a problem

by the rest of the family.

Gesell3 has contrasted the ease with which the 1-year-old child is put to bed with the difficulties experienced by the parents of many older children. The “typical” preschooler is described as likely to

insist upon a specific bedtime routine, request a

particular toy to take to sleep, call out to his or her

parents after being put to bed, and to awaken frequently during the night with reports of dreams or nightmares. Although numerous clinicians48 have confirmed and amplified Gesell’s observations, no clear answer is as yet available to the question, how many children are “typical”? Quantitative studies are rare, and, for the most part, have been confined to a consideration of a single age level within the first 2 years of lifeY’6

The data base of the New York Longitudinal

Study provided a unique opportunity to fill this

gap. The records maintained in the course of that anterospective investigation contain detailed

de-scriptions of the nature and duration of each child’s

bedtime routine and behavior during the night. Not

only has it proved possible to subject this

informa-tion to quantitative analysis, but the fact that the same children have been studied over time permits the examination of age trends without concern about sample comparability.

SUBJECTS

Received for publication Feb 12, 1982; accepted April 23, 1982. Reprint requests to (M.E.H.) New York Hospital-Cornell

Uni-versity Medical Center, 525 E 68th St, New York, NY 10021.

PEDIATRICS (ISSN 0031 4005). Copyright © 1983 by the

American Academy of Pediatrics.

Enrollment of subjects in the New York

Longi-tudinal Study began in 1956 and continued over a

6-year period. The sample included 133 children

(2)

parents were born in the United States; 87% of the

fathers and 89% of the mothers had some college

education, with 64% of the fathers and 36% of the

mothers having acquired postgraduate degrees; 75%

of the fathers were professionals or business

exec-utives, 20% were small businessmen, and 5% were

highly skilled artisans. By the time the children had

reached their fifth birthday, one third of the

moth-ers had returned to either full-time or part-time

work, and of these 80% were engaged in professional

occupations.”2

Expressed parental attitudes emphasized the

im-portance of identifying and satisfying the needs of

infants and young children. Permissiveness in

rela-tion to feeding and toileting was viewed as

partic-ularly desirable. However, as a group, these parents

were much concerned with the age at which their

children could assume responsibility for and exhibit

skifi in carrying out activities of daily living and

self-care. They often expressed the opinion that the earlier a child was able to sleep through the night,

feed himself, dress himself, tie his shoes, and so

forth, the better. Precocity in task mastery had high

prestige and status value for these families.’7

Spock’s manual, Baby and Child Care,’8 was

uniformly utilized as a source of child rearing

ad-vice, although a number of mothers felt free to

diverge from its specific recommendations on

oc-casion. Most of the families actively consulted their

pediatricians for guidance in the routine care of

their infants and young children. The parent group,

as a whole, was oriented toward the desirability of

obtaining psychiatric advice and, if necessary,

treat-ment for a child with deviant behavioral

function-ing.’9

The present report is based upon information

abstracted from the interviews conducted at 1, 2, 3,

4, and 5 years of age on 109 (82%) of the 133 New

York Longitudinal Study subjects. Six children

were eliminated because a review of records

mdi-cated that interviews had not been conducted for

two of the indicated ages, and the other 18 children

were eliminated because a single record was missing

from their folders. There is no evidence to suggest

that the children for whom available information

was incomplete were in any other way atypical.

METHODS

The methods of the New York Longitudinal

Study have been described elsewhere,”2 and will

therefore be only briefly summarized here. Parents

were the primary source of information concerning

their child’s behavior. Initial interviews were

con-ducted when the child was 3 months of age, at

3-month intervals until age 18 months, and at

6-month intervals until age 5 years. Parents were told

that the project studied the individual behavior of

normal children in normal homes. The interview

was designed to elicit detailed descriptions of be-havior in everyday life situations. The format of the

interview was semistructured in that the

inter-viewer was required to obtain answers to specific

questions, but the order ofpresentation was flexible.

Responses were recorded in narrative form. The

following aspects of sleep and bedtime behavior

were routinely explored. Parents were asked to

indicate the time and regularity of bedtime and

naptime behavior and to describe the bedtime rou-tine. They were also asked how long it took for the

child to fall asleep after being put to bed and to

recount his/her behavior during this interval.

Ad-ditional questions focused on whether or not the

child slept through the night. If the child awakened,

note was made of the frequency, behavior on

awak-ening, and what was required to get him/her back

to sleep. The time of and behavior on morning

awakening was also described.

For the purposes of the present examination of

sleep and bedtime behavior, each record was

ab-stracted to a protocol that permitted the recording

of the following information: (1) who usually put

the child to bed, (2) where the child slept, (3) the duration of the bedtime routine, (4) whether the child regularly took a specific blanket or toy to bed,

(5) whether the light was left on, (6) the length of

time required to fall asleep, (7) the frequency of

night awakening, and (8) the occurrence of night-mares and night terrors.

RESULTS

The analysis of the data addressed the following

aspects of sleep and bedtime behaviors: (1) sleeping

arrangements and adult supervision at bedtime, (2)

bedtime activities, and (3) interruptions of sleep. In

each instance, attention is directed toward the

de-termination of overall frequency of occurrence of

the specified behavior as well as the examination of possible sex differences and age trends.

Sleeping Arrangements and Adult Supervision at Bedtime

Sleeping Arrangements. All of the children slept

in their own crib or bed at each of the age levels

examined. Seventy-two percent of the children

shared a room at some time during the first 5 years

of life (Table 1). The sleeping arrangements of boys

and girls did not differ significantly

(f

= 0.237, df

= 1). However, the proportion of children sharing

a room was significantly different at different ages.

As the data of Table 1 indicate 29% of the children did so at 1 year of age as compared with 39% at age

2, 49% at age 3, 54% at age 4, and 49% at age 5 years

(3)

TABLE 1. Sleeping Arrangements and Adult Supervision at Bedtime Year 1 N (%) Year 2 N (%) Year 3 N (%) Year 4 N (%) Year 5 N (%) Ever N (%) Coch-ran Q dl P

Shares bedroom 32 (29) 43 (39) 53 (49) 59 (54) 56 (49) 78 (72) 33.97 4 <.001

Father regularly partici- 7 (6) 13 (12) 21 (19) 16 (15) 18 (17) 35 (32) 19.01 4 <.001

pates in bedtime routine

the most common roommates at all ages, but one

child at 1, 4, and 5 years of age regularly slept in

the parental bedroom. Other children regularly shared a room with a grandmother or housekeeper.

The arrangement was reported for one child at age

1, four children at age 2, five children at age 3, and

one child at age 4.

Adult Supervision at Bedtime. Maternal

super-vision of bedtime activities was the predominant

pattern during the preschool period. Nevertheless,

paternal participation at bedtime was reported for

32% of the children at some point during the first 5

years of life (Table 1). Fathers were equally likely

to become involved in the bedtime routines of girls

as of boys

(x2

= 2.2559, df = 1). However, as the

data of Table 1 indicate, significantly more fathers

participated in bedtime routines as the children

grew older. When children were 1 year of age, seven

fathers (6%) were involved in bedtime activities on

a regular basis as compared with 18 (17%) when

children were age 5 years (Cochran

Q

= 19.01, df

= 4, P < .001). Less than 5% of the children were

regularly put to bed by their grandmothers or housekeepers, but this arrangement was not de-scribed after 3 years of age.

Bedtime Activities

Duration ofBedtime Routine. A regular bedtime

routine, usually involving some combination of

dia-per change or toileting, drink from a bottle or glass,

song and/or story, followed by good night kisses,

was followed by all children of all ages. Sixty-six

percent of the children required more than 30

mm-utes for the execution of this routine on a regular

basis at at least one age level during the preschool

period. The number ofboys and girls whose bedtime

routines were prolonged did not differ significantly

(x2

= 0.0734, df= 1). However, as the data of Table

2 indicate, it took more than 30 minutes to put only

6% of the children to bed at 1 year of age as

compared with 12% at 2 years, 24% at 3 years, 49%

at 4 years, and 33% at 5 years. These differences

are significant at the 0.001 level of confidence

(Cochran

Q

= 73.02, df= 4). Moreover, two children

at 1 year of age, three children at age 2, and two

children at age 3 years were never actually put to

bed but were permitted to fall asleep elsewhere and

then carried into their own room.

Falling Asleep with Light On. Forty-seven

per-cent of the children regularly insisted on sleeping with the light on at at least one age level during the

first 5 years of life (Table 2). This. behavior was

exhibited with equal frequency by both boys and

girls ( = 0.2257, dl = 1). As the data of Table 2

indicate, increasing numbers of children, up to age

4 years, demanded that a light be left on. The

proportion of children sleeping in an ifiuminated

room was 7% at 1 year, 13% at 2 years, 22% at 3

years, 30% at 4 years, and 25% at 5 years of age.

These differences are significant at the 0.001 level

of confidence (Cochran

Q

= 24.54, df = 4).

Treasured Objects. Slightly more than three

fourths of the children regularly took a particular

toy or blanket to bed at at least one age level during

the preschool period (Table 2). The number of boys

as contrasted with girls who exhibited this behavior

pattern was not significantly different ( = 0.1567).

However, the frequency with which children made

such a demand was significantly different at differ-ent ages. As the data of Table 2 indicate, more than

40% did so at 2, 3, and 4 years of age as compared

with 20% at 1 and 5 years of age (Cochran

Q

=

154.48, df= 4, P < .001).

“Curtain Call” Behaviors. Seventy-five percent of the children regularly recalled their parents at least once every night after being put to bed at some point during the preschool period (Table 2).

These curtain-calls, which included requests for a

service such as a drink of water or another good

night kiss, occurred with equal frequency among boys and girls

(x2

= 0.3730, df = 1). However, as

indicated in Table 2, significantly greater numbers

of older children engaged in this behavior as

con-trasted with younger children. Fourteen percent of 1-year-old children displayed this pattern as

com-pared with 26% of 2-year-old, 42% of 3-year-old, 49%

of4-year-old, and 50% of 5-year-old children

(Coch-ran

Q

= 75.46, df = 4, P < .001).

Length of Time Required to Fall Asleep. Nearly

90% of the children frequently (three or more times

per week) required more than 30 minutes to fall

asleep at at least one age level during the preschool

period (Table 2). Boys and girls were equally likely

to experience delays in faffing asleep ( = 0.1094,

df = 1). The proportion of children in whom the

onset of sleep was frequently prolonged increased significantly with increasing age. As the data of

Table 2 indicate, 26% of the children exhibited this

(4)

TABLE 2. Selected Bedtime Activities in Preschool-Aged Children

Year 1 N (%)

Year 2 N (%)

Year 3 N (%)

Year 4 N (%)

Year 5 N (%)

Ever N (%)

Cochran Q

df P

Bedtime routine >30 mm 7 (6) 13 (12) 26 (24) 53 (49) 36 (33) 72 (66) 73.02 4 <.001

Falls asleep with light on 8 (7) 14 (13) 22 (20) 33 (30) 25 (23) 52 (47) 24.54 4 <.001

Requests treasured object 20 (18) 50 (46) 54 (50) 46 (42) 22 (20) 83 (76) 154.48 4 <.001

1 or more “curtain calls”! 15 (14) 28 (26) 46 (42) 53 (49) 55 (50) 82 (75) 75.46 4 <.001

night

Requires >30 mis to fail 28 (26) 47 (43) (17 (61) 75 (69) 72 (66) 96 (88) 70.52 4 <.001

asleep

age 5 years (Cochran

Q

= 73.02, df = 4, P < .001).

The behavior of the children during this period of

wakefulness also differed as the children grew older.

Until 2 years of age the majority of wakeful children

tended to talk or play quietly by themselves or with

a sibling. After age 3 years, children who

experi-enced a delay in falling asleep were far more likely

to call for their parents.

Interruptions of Ongoing Sleep

Nighttime Awakening. Ninety-five percent of the

children were described by their parents as

regu-larly crying or calling during the night as frequently

as once a week at at least one age level during the

first 5 years of life (Table 3). No sex differences

with respect to this pattern were observed

(x2

=

0.2393, df = 1). Moreover, similar numbers of

chil-dren exhibited this behavior at different ages. As

may be seen in Table 3, 57% awoke once a week at

ages 1 and 2 years, 66% at age 3 years, 65% at age 4

years, and 61% at age 5 years (Cochran

Q

= 4.29, df

= 4, P = not significant). Although the proportion

of children who regularly awoke one or more times

every night was smaller, 70% of the children were

noted to do so at some point during the preschool

period (Table 3). Again, with respect to the sex of

children exhibiting this behavior no significant

dif-ferences were found

(x2

= 0.9590, df = 1). The

frequency of occurrence of this pattern did not

differ significantly at different ages. Even at 5 years

of age nearly 20% of the children cried or called to

their parents at least once every night (Table 3).

Nightmares and Night Terror. Sixty-two percent

of the children were reported to have regularly

experienced nightmares as often as once every 2

weeks at some point during the preschool period

(Table 3). Nightmares occurred with equal

fre-quency in boys and girls

(x2

= 0.1541, df = 1). As

indicated in Table 3, nightmares were significantly

more likely in older children. This behavior was

described in 5% of 1-year-old children as compared

with 38% of 5 year olds (Cochran

Q

= 67.71, df = 4,

P < .001). Night terrors, characterized as episodes

of intense crying accompanied by difficulty in

arousal, were reported by the parents of a total of

seven children (6%) during the preschool period.

Two children exhibited night terrors at age 1 year,

none at age 2 years, two at age 3 years, and three at

4 and 5 years of age.

DISCUSSION

This report has utilized information from the

New York Longitudinal Study of Temperament and

Development to determine the age-specific

fre-quency of occurrence of selected aspects of sleep

and bedtime behavior in normally developing

chil-dren between the ages of 1 and 5 years. The

follow-ing age trends have been described: Older children

are significantly more likely than younger children

to exhibit a prolongation of bedtime routine, insist

on sleeping with the light on, take a treasured object

to bed, request parental attention after being told

good night, and experience delays in falling asleep.

However, the frequency of occurrence of night

awakening was not different at the different age

levels examined, although older children were

sig-nificantly more likely to report nightmares. Thus, the behavioral patterns displayed by these children

born and raised in New York City during the 1950s

are very similar to those described by Gesell3 as

occurring in preschool children living in New Haven

more than 30 years previously.

Our findings also closely resemble those of other

studies in which aspects of sleep and bedtime

be-havior have been examined from a quantitative

perspective. For example, Bernal’#{176} observed that

31% of the 77 predominately middle-class

12-month-old infants born in Oxford in the early 1970s

awakened at least once every night, as compared

with 29% of the children in the New York

Longi-tudinal Study. In the study of Ragins and Schacter’4

the proportions of 44 middle-class and lower

mid-dle-class 2-year-old children born in Pittsburgh

dur-ing the late 1960s who recalled a parent after being

put to bed, required more than 30 minutes to fall

asleep, regularly insisted on sleeping with a

partic-ular blanket or toy, or who awakened during the

night, are also closely similar to those found in the

present study. Although the results of an

investi-gation of 783 2#{189}-year-old children who attended

well baby clinics in Rochester in the 1940s’6 are not

(5)

TABLE 3. Interruptions of Sleep in Preschool-Aged Children Year 1 N (%) Year 2 N (%) Year 3 N (%) Year 4 N (%) Year 5 N (%) Ever N (%) Cochran Q dl P

Night awakening at least 62 (57) 62 (57) 72 (66) 71 (65) 66 (61) 104 (95) 4.29 4 NS once/wk

Awakens 1 or more times 32 (29) 30 (28) 36 (33) 32 (29) 21 (19) 76 (70) 3.57 4 NS every night

Nightmares at least once 5 (5) 10 (9) 31 (28) 42 (39) 41 (38) 68 (62) 67.71 4 <.001 every 2 wk

ages at which the children were examined, the

findings that 90% had a definite bedtime routine

and 44% regularly awakened during the night are in

general accord with those of the present study.

Furthermore, the proportion of children in this

sample who insisted on sleeping with a treasured

object during the first 2 years of life is no different

from that retrospectively reported by the parents

of school-aged children of similar social class born

in New York City some 15 years later.2#{176}

The similarity between the findings of studies of

children living at different times and in widely

disparate geographic areas and social circumstances

is striking, and raises the possibility that

age-spe-cific patterns of sleep and bedtime behaviors may

have a neurophysiolgoic base that undergoes

mat-urational change during the preschool period.

Re-cent reports have described shifts in the length of

the rapid eye movement (REM)-nonREM cycle

during the first 5 years of life.2’ Such

electrophys-iologic changes may well be expressed behaviorally

in the increased frequency of occurrence of reports

of nightmares among older children.

Analytic contributions to the understanding of

the sleep and bedtime behaviors of young children

have stressed the role of the growing complexity of

the mental apparatus in interfering with the

phys-iologic process of sleep.7 The development of

bed-time rituals and other delaying tactics, as well as

the emergence of nightmares, are believed by many

to reflect the child’s efforts at resolution of the

conflicts of the separation-individuation and

phal-lic-oedipal phases of development.22 In addition, as

Anna Freud is reported to have suggested, such

behaviors may represent a common range of

adap-tive behavior on the part of the human infant and

young child to the “unnatural” conditions in which

he is required to sleep (alone and between cold

sheets).7

The data of the present report lend support for

these views. The majority of children studied

en-gaged regularly in a prolonged and elaborate

bed-time routine, experienced delays in falling asleep,

and awoke frequently during the night at some

point during the preschool period. Such behavioral

patterns are frequently of concern to parents, either

because the behaviors themselves are inconvenient

or annoying or because they may be considered

symptomatic of more serious emotional

disturb-ance. Advice and guidance is most effectively

for-mulated and received within the context of a clear

understanding of the developmental course of sleep

and bedtime behavior during the first 5 years of life.

If a child is functioning well in other areas of life,

parents can be assured that age-stage typical

be-haviors are not of serious import, and they should

be encouraged to set limits appropriate to the needs

of both the developing child and his family.

ACKNOWLEDGMENTS

We thank Alexander Thomas, MD, and Stella Chess,

MD, for making the data of the New York Longitudinal

Study available to us.

REFERENCES

1. Thomas A, Chess 5, Birch HG, et al: Behavioral Individu-ality in Early Childhood. New York, New York University

Press,1963

2. Thomas A, Chess S: Temperament and Development. New

York, Brunner/Mazel, 1977

3. GeseIl A: The First Five Years of Life. New York, Harper and Brothers, 1940

4. Despert JL: Sleep in pre-school children: A preliminary

survey. Nervous Child 1949;8:8

5. Fraiberg S: On the sleep disturbances of early childhood. Psychoanal Study Child 1950;5:285

6. Healy A: The sleep patterns of pre-school children: General principles and current knowledge. Clin Pediatr 1972;11:174

7. Nagera H: Sleep and its disturbances approached

develop-mentally. Psychoanal Study Child 1966;21:393

8. Sperling M: Neurotic sleep disturbances in children. Nervous Child 1949;8:28

9. Anders TF: Night-waking in infants during the first year of life. Pediatrics 1979;63:860

10. Bernal JF: Night waking in children during the first 14

months. Dev Med Child Neurol 1973;15:760

11. Blurton-Jones N, Rossetti Ferreira MC, Farquar Brown M, et al: Association between perinatal factors and later night awakening. Dev Med Child Neurol 1978;20:427

12. Carey W: Night awakening and temperament in infancy. J Pediatr 1970;84:756

13. Moore T, Ucko LE: Night awakening in early infancy. Arch Dis Child 1957;32:333

14. Ragins N, Schacter J: A study of sleep behavior in two year old children. JAm Acad Child Psychiatry 1971;10:464 15. Richman N: A community survey of characteristics of

one-to-two year olds with sleep disruptions. J Am Acad Child Psychiatry 1981;20:281

(6)

Am JDiS Child 1951;82:127

17. Hertzig ME, Birch HG, Thomas A, et al: Class and ethnic

differences in the responsiveness of pre-school children to

cognitive demands. Monogr Soc Res Child Dev (series No. 117) 1968;33:1

18. Spock B: The Pocket Book of Baby and Child Care. New

York, Pocket Books, 1946

19. Thomas A, Chess 5, Birch HG: Temperament and Behavior

Disorders. New York, New York University Press, 1968 20. Sherman M, Hertzig ME, Austrian R, et al: Treasured

ob-jects in school-aged children. Pediatrics 1981;68:379

21. Kahn E, Fischer C: 24-Hour sleep patterns. Arch Gen

Psy-chiatry 1973;29:380

22. American Psychiatric Association: Syllabus: Psychiatric Knowledge and Skills Self-Assessment Program IV.

Wash-ington, DC, American Psychiatric Association, 1979

PIERRE BROUZET ON JEALOUSY AS A CAUSE OF FAILURE TO THRIVE

IN INFANCY (1754)

Pierre Brouzet (c. 1714-1772), the author of a two volume work on diseases of

children, first published in Paris in 1754,’ included jealousy as one of the causes

of poor nutrition in infancy.

He wrote:

When it is suspected that this leanness is owing to the infant’s pining we should

endeavour to discover what it is that makes him pine and we shall generally perceive

that greater fondness is shewn [sic] to some other infant in the house than to him, and

that on this account he is filled with jealousy. We cannot conceive the sensibility of an

infant in this respect: he conceals his uneasiness within his own heart and keeps it an

impenetrable secret; we must guess at his pain. The only means of discovering it is to

shew less fondness to his brother or sister to whom there has before been shewn a great

deal.

We should then carefully observe his eyes and we shall soon know if his disorder

proceeds from jealousy: for if it does, he will no sooner perceive this change than his

looks will become more serene and he will appear less melancholy and thoughtful than

usual. As soon as the mystery is discovered, all about him should in his presence avoid

all the caresses they were used to bestow on others and as much as possible bestow them

on him, but in such a manner that he does not perceive the plot . . . . That infants are

capable of jealousy is a point that cannot be doubted, they are so even while at the

breast.

REFERENCE

Noted by T.E.C., Jr, MD

(7)

1983;71;153

Pediatrics

Antonio U. Beltramini and Margaret E. Hertzig

Sleep and Bedtime Behavior in Preschool-Aged Children

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(8)

1983;71;153

Pediatrics

Antonio U. Beltramini and Margaret E. Hertzig

Sleep and Bedtime Behavior in Preschool-Aged Children

http://pediatrics.aappublications.org/content/71/2/153

the World Wide Web at:

The online version of this article, along with updated information and services, is located on

American Academy of Pediatrics. All rights reserved. Print ISSN: 1073-0397.

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