Gender and Discipline in 5-12 Month Old Infants

8/20/2019 Gender and Discipline in 5-12 Month Old Infants

1/11

Infant Behavior & Development 36 (2013) 199–209

Contents lists available at SciVerse ScienceDirect

Infant Behavior and Development

Gender and discipline in 5–12-month-old infants: A longitudinalstudy

Richard Evan Ahl a,1, Anne Fausto-Sterling b,∗, Cynthia García-Coll c , Ronald Seifer d

a Brown University, United Statesb Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, United Statesc Departments of Education and Cognitive, Linguistic Sciences and Psychology, Brown University, United Statesd Department of Psychiatry andHuman Behavior, Brown University, United States

a r t i c l e i n f o

Article history:

Received 31 August 2012

Received in revised form

28 November 2012

Accepted 12 January 2013

Keywords:

Gender

Discipline

Mother–infant interaction

Infancy

a b s t r a c t

We examined the effects of infant age and gender on the behaviors of infants and mothers

during discipline interactions using longitudinal, naturalistic, home-based, taped observa-

tions of 16 mother–infant dyads (eight males and eight females). These observations were

conducted between the child ages of 5 and 12 months and used a devised Maternal Dis-

cipline Coding System to code for the occurrence of discipline events. During discipline

interactions, mothers vocalized longer, used harsher tones, and used more explanations

with older compared to younger infants. Male infants were more likely than female infants

tocry or whine during discipline events. Mothers of male infants used longer vocalizations,

more words, and more affectionate terms than mothers of female infants. Male infants

were more difficult during discipline interactions than female infants, but it appeared that

mothers of males responded to this difficulty by using milder discipline techniques.

© 2013 Elsevier Inc. All rights reserved.

1. Gender and discipline in infancy

In their groundbreaking 1974 book on sex differences, Maccoby and Jacklin cited sex differences in aggression as one of

the few robust findings in the psychological literature. Since this important work much attention has focused on different

forms of aggression between girls and boys (Ostrov & Keating, 2004). Generally, it is believed that these different types of

aggression, which have the potentialto become disruptive and even anti-social in extreme manifestations, may emerge from

a variety of parenting characteristics,includingones thatalso promote insecure attachmentbehaviors. Despite a considerable

literature on sex differences in aggression and its relationship to attachment and on the potential negative consequences of

overly internalizing and overly externalizing behavior, there are very few studies of parent child disciplinary interactions

(a) with infants and (b) in which possible gender differences are examined (Casas et al., 2006; Kawabata, Alink, Tseng, van

Ijzendoorn, & Crick, 2011; Nelson, Hart, Yang, Olsen, & Jin, 2006). Here we report the results of a small study of mother infant

disciplinary interactions observed regularly over a several month period.

The literature on gender and discipline is far from clear. Straus et al. (1998) f ound that mothers generally discipline

young children more harshly than fathers, primarily due to the greater time mothers spend caring for their children. In a

survey-based study on parents of children between 4 and 35 months of age, Regalado, Sareen, Inkelas, Wissow, and Halfon

This work was supported by funding from the Ford Foundation and a Brown University summer fellowship for Richard Ahl.∗ Corresponding author at: Department of Molecular Biology, Cell Biology and Biochemistry, Box G, Brown University, Providence, RI 02912,

United States. Tel.: +1 401 863 2109.

E-mail addresses: Anne [email protected], [email protected] (A. Fausto-Sterling).1 Current address: Framingham Heart Study, 73 Mt. Wayte Avenue, Suite 2, Framingham, MA 01702-5827, United States.

0163-6383/$ – see front matter © 2013 Elsevier Inc. All rights reserved.http://dx.doi.org/10.1016/j.infbeh.2013.01.005

http://localhost/var/www/apps/conversion/tmp/scratch_4/dx.doi.org/10.1016/j.infbeh.2013.01.005http://localhost/var/www/apps/conversion/tmp/scratch_4/dx.doi.org/10.1016/j.infbeh.2013.01.005http://www.sciencedirect.com/science/journal/01636383mailto:[email protected]:[email protected]://localhost/var/www/apps/conversion/tmp/scratch_4/dx.doi.org/10.1016/j.infbeh.2013.01.005http://localhost/var/www/apps/conversion/tmp/scratch_4/dx.doi.org/10.1016/j.infbeh.2013.01.005mailto:[email protected]:[email protected]://www.sciencedirect.com/science/journal/01636383http://localhost/var/www/apps/conversion/tmp/scratch_4/dx.doi.org/10.1016/j.infbeh.2013.01.005


2/11

200 R.E. Ahl et al./ Infant Behavior & Development 36 (2013) 199–209

(2004) f ound that the sex of the child had no effect on parentally reported types of discipline. Socolar, Savage, Keyes-Elstein,

and Evans (2005) also found that child gender did not influence parental discipline in their study on parental discipline of

12–19-month-old children.

In an observation-based study of toddlers (14 months) and their mothers, Power and Chapieski (1986) f ound that the sex

of the child had no significant effect on the child’s rate of misbehavior (playing with forbidden objects) or the mother’s use of

discipline. Their review of similar studies found few sex differences in measures of toddler compliance and misbehavior. In

an observation-based study, Kochanska, Kuczynski, and Radke-Yarrow (1989) f ound that the sex of the child (16–44months)

had no bearing on maternal use of child management methods. More recent studies by Kochanska, however, have found

sex differences (Kochanska, 2001; Kochanska, Aksan, & Nichols, 2003; Kochanska, Coy, & Murray, 2001; Kochanska, Coy,

Tjebkes, & Husarek, 1998; Kochanska, Tjebkes, & Forman, 1998).

Using both survey and observational measures of maternal discipline and child misbehavior in 1–3-year-olds, van Zeijl

et al. (2007) f ound that mothers of boys and mothers of girls did not differ in their use of discipline strategies. However,

boys showed higher rates of physical aggression than girls. Lytton and Romney (1991) conducted a meta-analysis of 172

studies on child gender and parent behavior in an attempt to determine “whether parents make systematic differences in

their rearing of boys and girls” (p. 267). The study found few significant differences, but there was a slight tendency for

parents to use more physical punishment on boys than girls.

Miner and Clarke-Stewart’s (2008) findings of sex differences in child externalizing behavior raise important method-

ological issues. Mothers who did not use harsh discipline and had higher maternal sensitivity ratings were effective at

reducing levels of child externalizing behavior at later ages, an effect that was especially strong for boys. However, the find-

ing of sex differences in rates of child externalizing behavior depended upon the identity of the reporter, as teacher ratings

were significantly higher for the boys than for the girls. There was no significant difference between the ratings of mothers

of boys and the ratings of mothers of girls. The use of direct observations, rather than adult reporting methods, could help

determine whether the source of such differences stems from informant bias or contextual differences in child behavior.

The research of McFadyen-Ketchum, Bates, Dodge, and Pettit (1996) suggests that maternal discipline effects may have a

different trajectory for boys and girls. The study investigated whether levels of maternal coercion and non-affection during

discipline interactions predicted levels of child disruption and aggression from kindergarten to third grade. Although a

maternal behavior profile of high coercion and low affectionwas linked to increased levels of aggression during kindergarten

for boys and girls, the effects of maternal behavior on changes in the child’s behavioral profile depended on the child’s sex.

For boys, a high coercion/low affection behavior profile was associated with increased aggression over time. For girls, higher

levels of coercion actually predicted decreased aggression over time, and there was no relationship between maternal

affection and aggression changes.

Kochanskaet al.(1989, 2003) observed boys andgirlsin laboratory settings with their mothers duringthe ages of 14,22, 33

and 45 months. The observation scenarios consisted of “do” (toy cleanup) and “don’t” (refrain from touching attractive toys)

tasks. They found that mothers of boys used more power assertion than mothers of girls. Girls demonstrated higher rates

of empathy and maternal imitation than boys. Another study focused on rates of child compliance in response to maternal

requests and prohibitions (Kochanska et al., 2001). For the “do” task, girls showed higher rates of committed compliance

at 14 months, but rates for both sexes were similar for the subsequent age groups. For the “don’t” task, the sex differences

were more pronounced: girls showed significantly higher rates of committed compliance at every age group.

To sum up, some studies (Kochanska et al., 1989; Power & Chapieski, 1986; Regalado et al., 2004; Socolar et al., 2005; van

Zeijl et al., 2007) have found that mothers of boys and girls have similar patterns in overall discipline practices, while others

(Kochanska et al., 2003; Laumann, Michael, & Gagnon, 1994) have found differences. The direction of causality in studies

that find sex differences is usually unclear, i.e. whether mothers use more harsh discipline on boys because they misbehave

more frequently or whether the harsh discipline causes more misbehavior, or both.

1.1. Using dynamic systems theory to study gender and discipline

Many studies on maternal discipline and child behavior only use survey data, making it difficult to determine what an

actual discipline event looks like, the complexities of the dyadic exchange, the contextual factors that influence how the

event unfolds, etc. Moreover, much of the observational research has been conducted using experimentally manipulated

scenarios designed to elicit discipline events (i.e. the “do/don’t” tasks). While these approaches are important, they do not

necessarily clarify the types of discipline that occur in everyday situations. Exceptions include the work of Hollenstein and

colleagues who use state space grids to analyze moment by moment dynamics of disciplinary interactions between mothers

and children (Granic, Hollenstein, Dishion, & Patterson, 2003; Hollenstein, Granic, Stoolmiller, & Snyder, 2004).

Many studies restrict observations to a small number of sessions conducted several months apart. While less labor and

time-intensive, this approach may miss subtle changes in discipline interactions over time. Finally, it is important to conduct

research on the discipline of very young children. Results from survey-based studies have shown that parents do discipline

their children between the ages of 5 and 12 months, but very little observation-based work has examined this age group.

It is unclear, for instance, how discipline practices at 5 months differ from discipline practices at 12 months. The greatest

potential to set healthy patterns of discipline could be during early infancy (see Ravn et al., 2011, 2012) before the onset of

discipline challenges that are created during the child’s second year of life. For these methodological and theoretical reasons


3/11

R.E. Ahl et al. / Infant Behavior & Development 36 (2013) 199–209 201

we examined the effects of infant age and gender on the behaviors of infants and mothers during discipline interactions

using longitudinal, naturalistic, home-based, taped observations of 16 mother–infant dyads.

2. Methods

2.1. Participants

The participants consisted of 16 mother–infant pairs (8 male infants, 8 female infants) initially recruited for a study oninfant temperament. Families were first contacted during the lying-in period at the university obstetrics hospital, which

accounted for more than 90%of the births in the state of Rhode Island. Direct contact was made with white, first time

mothers who were 20 years of age or older. Subsequent contact, explanations of the project and obtaining of agreement

to participate resulted in a sample of families that was relatively affluent, intact, homogeneous, and motivated to continue

with an intensive longitudinal study commitment. Thus all of the enrolled mothers, taped in the early 1990s, were married,

white, first-time mothers with a mean age of 29.1 (SD= 4.2). The families had an average maternal Hollingshead ISP of 48.38

(SD= 8.91), paternal Hollingshead ISP of 48.75 (SD= 15.07), and 4-factor SES of 1.81 (SD=.75) (Seifer et al., 1994). After the

coding was completed, independent samples t tests comparing the families of male infants and female infants revealed that

mothers of male infants (M =7.13, SD= 1.25) had a significantly higher mean occupation status (Hollingshead) than mothers

of female infants (M = 5.63, SD= 1.41), t (14) = 2.26, p = .04. Male and female infants’ families did not differ for any of the other

parental variables, including maternal education. Independent samples t tests revealed no significant differences between

males and females on any of the temperament variables.

2.2. Materials

The original videotapes contained sessions that typically lasted for 1 h. In each session, the mother was asked to spend

at least 10min in each of the following situations: (a) play with infant, (b) caretaking with infant and (c) infant alone (with

the mother supervising the infant’s activities but not partaking in them). Taping was conducted weekly, with some missed

weeks for each family due to vacations, illness, etc. The vast majority of taping sessions were conducted in the living rooms

or play rooms of the participants’ homes. A small number of taping sessions were conducted outdoors. The percentage of

outdoor observations was similar across all participants.

We analyzed 251 7-min taped observations. From each taping session, a continuous, 7-min segment of “play with infant”

footage was selected. Brief interruptions of the observation (i.e. answering the phone) were allowed, but if the total length

of interruptions in the clip exceeded 1 min in length, the observation was discarded. An observation would also be discarded

if other children or adults were involved in the observation, if the audio or video was damaged, or if the cohesiveness of

the observation was fundamentally altered in any other way (i.e. a switch to a caretaking task during the middle of theobservation).

The Maternal Discipline Coding System summarized in Table 1, designed by Richard Ahl, was used to analyze the footage.

The Observer XT (Noldus) was used to code the footage and perform basic analyses. SPSS was used for most of the statistical

analyses. If the assumptions of Mauchly’s Test of Sphericity, Box’s Test of Equality of Covariance Matrices, and Levene’s Test

Table 1

Discipline event code definitions.

Maternal codes Definition

Affectionate terms Mother’s vocalization contains an affectionate term for her infant

Description o f infant m isbehavior Mother f ully or p artly describes t he infant’s m isbehavior

Distraction/alternative Mother distracts infant (toy, hugging, etc.) during or


4/11


of Equality of Error Variances have not been met we note this in the text. The term “mixed between-within subjects ANOVA”

is synonymous with “mixed-design, repeated measures ANOVA” (Pallant, 2007).

2.3. Observation selection

Monthly observations were selected from the tapes collected during the infants’ months 5–12. A total of 251 7-min

observations were analyzed. The tapes were divided into 4 age groups: 5–6, 7–8, 9–10, and 11–12 months. For 13 of the

16 dyads, four 7 min observations that met the above-described criteria, from each age group were analyzed, for a total of 16 observations per dyad. For most dyads, this meant using two observations taped during each age month. Observations

were chosen from as close to the middle of the month as possible. For some of the age groups, three dyads only had three

satisfactory observations for the given age group. Averages from the other same-gender dyads for the given age group were

calculated and then inserted in place of the missing observations.

2.4. Coding

We first watched each 7 min segment once, noting any possible instances of child misbehavior or reactive maternal

discipline. The information gathered in this initial step was used to help create the Maternal Discipline Coding System,

which we applied in the second and third steps of the coding process. These initial observations confirmed that each dyad

had a similar distribution of observations with restricted/non-restricted infant motion, a similar distribution of locations,

and a similar distribution of “free access” observations.

During a second viewing, each observation was coded for the presence of discipline events using The Observer, accord-ing to the guidelines of the Maternal Discipline Coding System. In devising the discipline event code we follow Belsky,

Woodworth, and Crnic (1996), who defined Child Behavior Management Events as “explicit efforts by either parent to con-

trol or direct the child’s behavior” (p. 562), with the exception of rule-based play (i.e. ‘you should put the square on top of

the circle, not on top of the triangle,’ or ‘no, don’t put the toy truck on top of the garage; it belongs inside the garage’ would

not be coded as discipline events). The criteria for the discipline event code are given in Table 1. During a third viewing,

descriptive codes were added to the discipline events (i.e. did the infant display negative affect during or immediately after

the discipline event?). For simplicity and consistency, the term ‘misbehavior’ will be used to describe the infants’ actions

that provoke disciplinary responses from their mothers.

2.5. Coding: reliability

We developed our coding scheme for infant discipline in three stages, which are described in detail in Appendix 1. Asdescribed, during phase 2 of the development process we conducted reliability trials using a trained reliability partner who

independently double-coded 10 observations containing discipline events. These observations were of dyads used to develop

the coding scheme, but these specific observations were not used for purposes other than the reliability trials, i.e. they were

not included in the data analysis. We took this approach because we were concerned with developing a coding scheme that

was unambiguous. Reliability analysis for the codes used in this study produced kappa values ranging from .67 to .89, with

a mean kappa value of .80.

3. Results

3.1. Discipline event length

A mixed between-within subjects (repeated measures) analysis of variance was conducted to assess the effects of child

gender and age on discipline event length (in seconds). This analysis examined whether the average length of a disciplineevent was longer for male or female infants and their mothers, and for infants at different ages. We hypothesized that male

infants would have longer discipline events than female infants, and that discipline event length would increase with age.

There wasno significant main effectfor child age(Wilks’ Lambda= .87, F (3,12)=.58, p= .64,2p = .13) orfor child gender(F

(1,14)= 2.28, p =.15,2p = .14). However, the interaction between child gender andage was significant (Wilks’ Lambda= .36, F

(3,12)=7.23, p= .005,2p = .64). As depicted in Table 3, the influence of child genderon discipline event lengthwas moderated

by child age. While male infants and female infants had similar discipline event lengths at the ages of 5–6 months and 11–12

months, male infants had longer discipline events than female infants at the ages of 7–8 months and 9–10 months. To clarify

the nature of the interaction, follow-up protected independent samples t tests were conducted to compare the discipline

event lengths of male infants to those of female infants at the ages of 7–8 months and 9–10 months.

For the 7–8 month age group, there was no significant difference in discipline event length between male infants

(M = 12.76, SD= 11.58) and female infants (M = 8.64, SD= 2.46), t (14) = .99, p=.34. For the 9–10 month age group, how-

ever, male infants and their mothers (M = 10.65, SD= 2.49) had significantly longer discipline events than female infants and

their mothers (M =6.07, SD= 1.73), t (14) = 4.28, p= .001.


5/11


Table 2

Maternal vocalization word count, by child gender and age.

Infant age 5–6 months 7–8 months 9–10 months 11–12 months

Mothers of males: mean word count (SD) 14.63 (2.43) 17.38 (6.41) 17.76 (3.65) 13.60 (6.16)

Mothers of females: mean word count (SD) 10.45 (3.23) 12.54 (4.06) 8.92 (3.02) 13.15 (4.58)

3.2. Total discipline event duration (per observation)


gender and age on total discipline event duration (the sum of alldiscipline event lengths for a single observation, in seconds).

We hypothesizedthat male infants would have longerdurationsthanfemale infants, andthatolderinfants would have longer

durations than younger infants. Because the assumption of equality of covariance matrices was violated according to Box’s

Test of Equality of Covariance Matrices, adjustments were made. Results from months 5–6 and 7–8 were averaged, creating

a new age group of 5–8. Results from months 9–10 and 11–12 were averaged, creating a new age group of 9–12. After this

adjustment, Box’s Test was no longer violated. However, since the assumption of Levene’s Test of Equality of Error Variances

was violated, the significance threshold was changed from .05 to .025.

The interaction between child age and gender was not significant (F (1,14) = .50, p=.49, 2p = .04), and there was no

significant main effect for age (F (1,14)= .25, p= .63, 2p = .02). The main effect for child gender was marginally significant

(F (1,14)= 5.33, p =.037, 2p = .28 where the significance threshold was dropped to p= .025) as shown in Table 4. Averaged

across all age groups, the mean discipline event total duration for male infants and their mothers was 11.56 (SD= 6.73),

nearly twice the mean of 5.82 for female infants and their mothers (SD= 2.04).

3.3. Maternal behavior

3.3.1. Maternal vocalization length during discipline events


gender and age on maternal vocalization length (in seconds). We hypothesized that mothers of females would use longer

vocalizations than mothers of males, and that mothers would use longer vocalizations as their infants grew older. The

interaction between child gender and age approached significance (Wilks’ Lambda= .54, F (3, 12) = 3.40, p= .054, 2p = .46).

The effect of gender was moderated by age, being most pronounced at the 7–8 and 9–10-month age groups, as depicted in

Table 5. There was a significant main effect for age (Wilks’ Lambda= .45, F (3, 12) = 4.84, p= .02, 2p = .55).

There was a significant main effect for gender, F (1,14) = 5.01, p= .04, 2p = .26, with mothers of males having longer voca-

lizations than mothers of females. Because of the near significant interaction between gender and age, follow-up protected

independent samples t tests were conducted to compare the effects of child gender on maternal vocalization length in the

7–8 and 9–10-month age groups. For the 9–10-month age group, the mean vocalization length for mothers of male infants

(M =7.86, SD= 2.11) was significantly longer than the mean vocalization length for mothers of female infants (M = 4.29,

SD= 1.53), t (14) = 3.88, p= .002. Results for the 7–8-month group were not significant (t (14) = 1.67, p =.12).

3.3.2. Maternal vocalizationword count


gender and age on maternal vocalization word counts (the number of words mothers used during discipline events). We

hypothesized that mothers of females would use more words than mothers of males, and that mothers would use more

words as their infants grew older.

The interaction between child gender and age was significant (F (3, 42) = 3.11, p= .036, 2p = .18). As depicted in Table 5,

the effects of child gender were stronger during the 5–6, 7–8, and 9–10-month age groups than during the 11–12-month

age group. The main effect for age was not significant (F (3, 42) = 1.08, p= .37), but there was a significant main effect for

gender (F (1, 14) = 10.42, p= .006, 2p = .427). Mothers of males used significantly more words during their discipline-related

vocalizations and had higher word counts than mothers of females.

To clarify the nature of the interaction between child gender and age, follow-up protected independent samples t tests

were conducted to compare the effects of child gender on maternal vocalization word counts in the 5–6, 7–8 and 9–10-

month age groups. For the 7–8 month age group, there was no significant word count difference between mothers of males

and mothers of females (t (14) = 1.80, p= .93). There were significant differences in the 5–6 month group (t (14) = 2.92,

p= .011), and the 9–10 month group (t (14) = 5.27, p= .000), with mothers of males using significantly more words during

discipline-related vocalizations than mothers of females. Means are displayed in Table 2.

3.3.3. Maternal vocalization tone


gender andage on maternal vocalizationtone (the tone/affective properties of themother’svocalizationduring thediscipline

interaction on a scale from 1 to 5, with lower scores corresponding to harsher vocalizations). We hypothesized that mothers

of males would use harsher tones than mothers of females, and that mothers would use harsher tones as their infants grew


6/11


Table 3

Effects of child gender and age on discipline event length.

Age 5–6 months 7–8 months 9–10 months 11–12 months

Discipline event length: boys (SD) 7.96 (1.93) 12.76 (11.58) 10.65 (2.49) 9.08 (3.63)

Discipline event length: girls (SD) 9.18 (2.39) 8.64 (2.45) 6.07 (1.73) 8.93 (3.55)

Table 4Effects of child gender and age on total discipline event duration.

Infant age 5–8 months 9–12 months

Total discipline event duration boys (SD) 10.37 (7.25) 12.74 (9.66)

Total discipline event duration girls (SD) 6.02 (3.11) 5.61 (2.13)

older. The interaction between child gender and age was not significant (F (3, 42) = .77, p=.52, 2p = .05). The main effect for

child gender was not significant (F (1,14)= .63, p=.44, 2p = .04).

However, there was a significant main effect for age (F (3, 42) = 4.45, p= .008, 2p = .24). The mean tone of vocalizations

to younger infants was more positive (higher score) than the mean tone of vocalizations to older infants. Two follow-up

protected paired samples t tests were conducted to compare the mean tone used during 5–6 months to the mean tone

used during 11–12 months, and to compare the mean tone used during 7–8 months to the mean tone used during 11–12

months. Mean tone scores were significantly higher (more positive) during 5–6 months (M = 3.36, SD=.49) than 11–12months (M =2.84, SD= .55) (t (15) = 2.98, p= .009), and significantly higher during 7–8 months (M = 3.15, SD= .39) than 11–12

months (t (15) = 2.16, p= .047).

3.3.4. Use of explanation/reasoning


gender and age on the percentage of maternal vocalizations containing explanation/reasoning during discipline events. We

hypothesized that mothers of females would use more explanation/reasoning than mothers of males, and that mothers

would use more explanation/reasoning as their infants grew older. Neither the interaction between child gender and age (F

(3, 42) = 1.66, p =.19, 2p = .11) nor the main effect for child gender were significant (F (1, 14) = .50, p=.49, 2p = .03).

However, themain effect forchildage wassignificant (F (3,42)=3.53, p= .023,2p = .20). Three follow-up protected paired

samples t tests compared the explanation usage in different infant age groups. Mothers used significantly more explanations

during the infant ages of 7–8 months (M = 33.35, SD= 26.73) than 5–6 months (M = 21.02, SD= 18.30), t (15) = 2.23, p= .042.

Mothers used significantly more explanations during the infant ages of 11–12 months (M = 42.24, SD= 31.38) than 5–6months, t (15) = 2.75, p= .015, and more explanations during 11–12 than 9–10 months (M = 24.66, SD= 21.48), t (15) = 2.16,

p= .048.

3.3.5. Use of affectionate terms


gender and age on the percentage of maternal vocalizations containing affectionate terms during discipline events. We

hypothesized that mothers of females would use more affectionate terms than mothers of males, and that mothers would

use fewer affectionate terms as their infants grew older.

Because the assumption of equality of covariance matrices was violated according to Box’s Test of Equality of Covariance

Matrices using four agegroups, adjustments weremade.Results from months5–6 and7–8 were averaged,creating a newage

group of 5–8. Results from months 9–10 and 11–12 were averaged, creating a new age group of 9–12. The mixed between-

withinsubjects analysis of variance wasconducted again;this time, only two age groups (5–8 and 9–12) were used instead of

four agegroups. After this adjustment, theassumption of Box’s Test of Equality of Covariance Matrices was no longerviolated.

However, since the assumption of Levene’s Test of Equality of Error Variances was violated, the significance threshold was

adjusted from .05 to .025.

Neither the interactions between child gender and age (F (1,14)= .001, p =.98, 2p = .00) nor the main effect for age were

significant (F (1,14)= 3.31, p=.09, 2p = .19). The main effect for gender approached significance (F (1,14)= 4.37, p= .055,

2p = .24). Due to the marginally significant main effect for gender, the lack of a significant interaction and the lack of a

significant main effect for age, and due to the skewed distribution of the data, a Mann–Whitney U test was conducted to

Table 5

Effects of child gender and age on maternal vocalization length.

Infant age 5–6 months 7–8 months 9–10 Months 11–12 Months

Mothers of males vocalization length in seconds (SD) 5.64 (1.78) 11.32 (10.15) 7.86 (2.11) 5.83 (2.45)

Mothers of females vocalization length in seconds (SD) 4.22 (1.44) 5.20 (2.07) 4.29 (1.53) 6.53 (2.52)


7/11


Table 6

Effects of child age and gender on child displays of negative affect.

Infant a ge Percentage o f events c ontaining infant n egative affect

Males (SD) Females (SD)

5–8 months 18.68 (16.06) 11.56 (9.06)

9–12 months 14.98 (11.88) 01.93 (3.39)

compare mothers of male infants’ use of affectionate terms to mothers of female infants’ use of affectionate terms. The use

of affectionate terms for all four age groups was averaged, and then a Mann–Whitney U test was performed. Mothers of

male infants (MD= 17.97,n= 8) used significantly more affectionate terms than mothers of female infants (MD= 5.94, n=8),

U = 13.00, z = 2.00, p= .045, r =.50.

3.4. Infant behavior

3.4.1. Display of infant negative affect


gender and age on the percentage of discipline events containing displays of infant negative affect. We hypothesized that

male infants would display negative affect at higher rates than female infants, and that infants would display negative affect

at higher rates as they grew older.

Because the assumption of equality of covariance matrices was violated according to Box’s Test of Equality of Covariance

Matrices using four age groups, adjustments were made. Results from months5–6 and7–8 were averaged, creating a newage

group of 5–8. Results from months 9–10 and 11–12 were averaged, creating a new age group of 9–12. The mixed between-

withinsubjects analysis of variance wasconducted again; this time, only two age groups (5–8 and 9–12) wereused instead of

four agegroups. After this adjustment, theassumption of Box’s Test of Equality of Covariance Matrices wasno longer violated.

However, since the assumption of Levene’s Test of Equality of Error Variances was violated, the significance threshold was

adjusted from .05 to .025.

Neither the interaction between child gender and age (F (1,14) = .56, p =.47, 2p = .04) nor the main effect for age were

significant (F (1,14)= 2.83, p= .12, 2p = .17). However, the main effect for gender was significant (F (1,14)= 6.70, p= .021,

2p = .32),as shown in Table 6. A significantly higherpercentageof disciplineevents involving male infants contained displays

of negative affect than events involving female infants. Male infants were significantly more likely to display negative affect

during/after discipline events than female infants. A Mann–WhitneyU test was conducted to compare male infants’ display

of negative affect to female infants’ display of negative affect. The negative affect percentage for all four age groups wasaveraged, and then a Mann–Whitney U test was performed. Male infants (MD= 13.23, n= 8) displayed significantly more

negative affect than female infants (MD= 7.41, n=8), U = 13.00, z = 1.99, p= .046, r = .49.

3.4.2. High and low discipline event groups

Based on their rates of discipline events during the ages of 9–12 months, infants were divided into two groups. The “High

discipline/misbehavior” group consisted of 7 infants (4 males, 3 females) who had an average of at least 1.1 discipline events

per observation during the ages of 9–12 months. The “Low discipline/misbehavior” group consisted of 7 infants (3 males,

4 females) who had an average of less than .65 discipline events per observation. (Two infants, one with an average of .88

discipline events per observation and the other with an average of 1.0 discipline events per observation, were excluded from

the grouping.)

Independent samples t tests were conducted to compare the High and Lowgroups on the parental SES and infant temper-

ament variables, both of which were previously collected by Seifer et al. (1994). Fathers’ occupation levels were significantly

lower for the High group than the Low group, t (12) = 2.97, p= .012. Fathers of high-discipline infants (M = 4.57, SD= 2.07)had significantly lower occupation statuses than fathers of low-discipline infants (M =7.71, SD= 1.89). Infant mood scores

at both 6 (t (12) = 3.90, p=.002) and 9 months (t (12) = 2.63, p= .02) were significantly higher for the High group than the

Low group. High mood scores indicate higher levels of “sadness and fussiness”. Thus, high-discipline infants (6 months:

M = 10.56, SD= . 51; 9 mo: M = 10.19, SD=.56) had significantly higher levels of sadness and fussiness at 6 and 9 months

than low-discipline infants (6 months: M =9.56, SD= .44; 9 months: M = 9.34, SD= .65). Total infant difficulty (9 months)

scores were significantly higher for the High group than the Low group, t (12) = 2.24, p= .045. High difficulty scores indicate

higher levels of temperamental difficulty. High-discipline infants (M = 37.18, SD= 1.40) had significantly higher levels of

temperamental difficulty at 9 months than low-discipline infants (M = 34.77, SD= 2.48).

3.5. Discipline event latency


gender and age on discipline event latency (the amount of time that passesbetween thechild’s misbehavior andthe mother’s


8/11


Table 7

Summary of results for the interactions of age and gender on discipline events.a

Significant (yes); not significant (no) Age: main

effect

Age×gender:

interaction

Gender: main

effect

Mann–Whitney U test

Discipline event length No Yes No –

Total discipline duration Yes No Marginal –

Maternal vocalization length during discipline Yes Marginal Yes –

Maternal vocalization word count during discipline No Yes Yes –

Maternal vocalization tone Yes No No –Use of explanation/reasoning Yes No No –

Use of affectionate terms No No Marginal More affectionate terms to males

Infant negative behavior No No Yes Males have more negative behavior

a For specifics of statistical analysis see Tables 1–6 and the text of Section 3.

response to it, measured in seconds). It was hypothesized that male infants would have shorter latencies than female infants,

and that latencies would decrease as infants grew older. Neither the interaction nor the main effects were significant.

3.6. Summary of gender and age results

Because of the diversity of our test results we have produced a single table summary (Table 7) for significant or non-

significant results for tests of age, gender and age–gender interactions. The details of our statistical analysis have been

presented in the previous section. The most surprising findings are that, while male infants exhibit more negative behavior,mothers appear to respond to males with more affectionate words, and use more words and talk for longer to boys during

discipline events.

4. Discussion

4.1. Overview

Little observational work has been done on discipline interactions between infants under the age of 12 months and their

mothers, andmost existing work is cross-sectional. This study of 8 boys and8 girls andtheir mothers, observed monthly from

5 to 12 months is a first step toward filling this knowledge gap. Based on the literature, we hypothesized that male infants

would have higher rates of discipline events (due to both higher rates of misbehavior and mothers’ heightened tendency

to respond to male infants’ misbehaviors) and would be more emotionally reactive during discipline interactions; in turn,

we thought that mothers would use harsher forms of discipline toward their male infants. Instead, we found that althoughmale infants displayed more negative affect during discipline events, mothers used milder forms of discipline with male

than with female infants. During discipline events mothers vocalized more to male infants and used more words and more

affectionate terms with male than female infants.

One of the most surprising findings was that membership in the “high discipline” group was not associated with any

maternal SES variables, but it was associated with lower father occupational status. The fathers of infants in the “high

discipline” group had significantly lower occupation statuses than those in the “low discipline” group. While it would seem

more likely for mothers’ SES to affect the nature of mother–infant interactions than fathers’, as fathers were not included

in our taped observations, findings that fathers’ class status correlate with patterns of child management difficulty are not

unprecedented (Belsky et al., 1996).

4.2. Child age and temperament

We found that as infants grow older, mothers subtly change their behavior during discipline events. When compared

with younger infants, mothers of older infants vocalized longer during discipline events, weremore likely to explain the con-

sequences of their infants’ misbehavior, and were more likely to use harsher, prohibitive tones. These three developmental

findings (an increase in mothers’ vocalization length, use of explanations, and use of harsher tones over time) have not pre-

viously been documented in 5–12-month-old infants. However, they are not surprising. Regalado et al.’s (2004) decision not

to ask mothers with infants under the age of 19 months about their use of ‘explaining’ was based on the belief that mothers

of younger children would rarely use this discipline strategy. Our findings show that the use of explanations increases as

children grow older during the first year of life, but also that even mothers of young infants regularly utilize this technique.

In our study the coding of a discipline event required an infant misbehavior and a maternal response, both of which had

to meet certain criteria. Each of the mothers had slightly different standards for which behaviors were acceptable, which

behaviors could have negative or dangerous outcomes, etc. Some mothers were more likely to interpret seemingly benign

infant actions as misbehaviors. Still, our qualitative impressions suggest that the children with the highest rates of discipline

events also had the highest rates of clear-cut misbehavior. These impressions also accord with the positive relationship we

found between difficult infant temperament and more discipline events, suggesting that the children’s overall dispositions


9/11


partially influenced the number of discipline events. We found that the group of 7 children with the highest average number

of discipline events per observation had significantly “sadder and fussier” moods at the ages of 6 and 9 months, and higher

overall “temperamental difficulty” at 9 months, than the group with the lowest number of discipline events. Our findings are

consistent with those of Kochanska et al. (2001), Socolar et al. (2005), Wissow (2002), Regalado et al. (2004), and Hendrix

(2004), all of whom found a relationship between temperament profiles and parental discipline practices. Since there were

no significant differences in temperament scores between the male and female children, our findings of gender differences

cannot be attributed to gender differences in temperament.

4.3. Gender analyses

Male infants between 5 and 12 months had an average of 1.3 discipline events per 7-min observation, and female infants

had an average of .75. These rates are similar to those found by other studies, attesting to the validity of our methods and

results. Power and Chapieski’s (1986) study of infants with a mean age of 13.7 months found a rate of one discipline event

every 9 min. Belsky et al.’s (1996) study of male infants between 15 and 21 months found a rate of one discipline event

every 6 min.

We also found gender differences, some marginal, in the lengths and types of maternal and infant behaviors during

discipline events.In the9–10 month agegroup,the average discipline event lengthfor male infants (10.65s) wassignificantly

longer than the average length for female infants (6.07). Males had marginally, but not significantly, longer total discipline

event durations than females. (Duration analyses relate to both the length of discipline events and the number of discipline

events.) The lack of significant findings for the latency code suggests that the greater amount of time male infants spend in

disciplineevents cannot be attributedto theirmothers waiting longerbefore disciplining them;rather, the genderdifferences

are being driven by what happens once the mother starts to intervene. The length of the maternal intervention is a product

of both how long the mother chooses to issue discipline (through vocalization and/or through physical intervention) and

the child’s reaction to her discipline. However, due to the generally low levels of observed overt infant defiance, it seems

unlikely that infant defiance was responsible. Instead, longer maternal interventions, irrespective of infant behavior, seemed

to lie at the heart of the difference. The length of maternal physical interventions was not measured in this study, but since

results from measures of maternal vocalization length showed that mothers of male infants used longer vocalizations, their

longer discipline behaviors cannot be attributed solely to longer physical interventions.

Mothers of male infants used significantly longer vocalizations and more words than mothers of female infants during

discipline events, a pattern opposite to what we had hypothesized. A literature review on child gender’s effects on maternal

vocalization found that mothers talk more to female infants than male infants in general, in a variety of non-disciplinary

contexts (Fausto-Sterling, García Coll,& Lamarre, 2012). Thus,mothers of boysare usinglonger vocalizations during discipline

events despite having a general profile of shorter and fewer vocalizations in non-discipline situations.

Another reason why the finding of longer vocalizations to male infants is surprising is that previous research links longer

vocalizations to milder (Pfiffner & O’Leary, 1989) and“warmer” (Grusec & Goodnow, 1994) discipline, and found that mothers

of male children are less likely to use these forms of discipline (Kochanska et al., 2003; Lytton & Romney, 1991). On the other

hand, longer vocalization and discipline event bouts could be associated with coercive discipline in older children (Belsky

et al., 1996; McFadyen-Ketchum et al., 1996); but we did not observe much coercive discipline in the present range of

observations. One could argue that longer vocalization is actually an indication of harsher discipline, but in this study, longer

vocalizations seemed to be associated with lengthier explanations. Pfiffner and O’Leary (1989) f ound that longer, milder

verbal discipline was less effective for children between the ages of 18 and 31 months than shorter, harsher discipline,

but other researchers have found short vocalizations lacking in explanations to have detrimental long-term consequences

(Kochanskaet al., 2003; Miner & Clarke-Stewart,2008; vanZeijlet al., 2007). Dueto the lack ofconsensus inthe literature,it is

unclear as to whether mothers of boys’use of longer vocalizations indicate either adaptive or problematic disciplinepractices.

The fact that there were no significant differences in vocalization length or word count between mothers of male and

female infants during 11–12 months could suggest that the differences seen at younger ages disappear at this age group.

Or, it could be attributed to specific data characteristics in this age group caused by the coding system’s definitions. In the

11–12 month age group, it became more common for short discipline events of the same type to happen in succession (for

instance, the mother removes a toy from the infant’s mouth, the infant puts the toy back in his or her mouth, and then this

process repeats). Each discipline event and accompanying vocalization would be short, but the overall vocalization duration

for the total observation would be long. Overall vocalization duration, however, was not measured in this study.

The finding of longer vocalizations to male infants does not by itself help us place mothers’ discipline of male and female

infants on a spectrum from harsh to mild. With the results of affectionate term usage analyses, a more complete picture

emerges. Mothers of male infants used more affectionate terms during their vocalizations than mothers of female infants.

This suggests that mothers of males maybe using milderdiscipline than mothers of females. In summary, none of ouranalyses

of maternal discipline practices revealed that mothers of boys used harsher or more power-assertive discipline than mothers

of girls, while three of the analyses suggested that mothers of boys may be using milder discipline than mothers of girls.

For the infant behaviors, only one analysis yielded significant results. Male infants were more likely to display negative

affect during discipline events than female infants. (The main effect for gender was marginally significant using the mixed

between-within subjects ANOVA,and significantusing the Mann–WhitneyU test.)The main effectfor agewas notsignificant,

although it is worth noting that, for female infants, the percentage of discipline events in which negative affect wasdisplayed


10/11


declined from 11.6% during 5–8 months to 1.9% during 9–12 months. For male infants, the percentage only declined from

18.7% to 15.0%.

Because previous research found boys above the age of 2 to be more likely to respond to aversive events with aggression

than girls, we had hypothesized that males would display more negative affect than females (McFadyen-Ketchum et al.,

1996). We reasoned that a negative affect response could lead to harsher maternal discipline. The negative affect results

accord with the first part of the hypothesis. However, the results on vocalization length and use of affectionate terms are at

odds with the second part. The results raise the possibility that, between the ages of 5 and 12 months, male infants’ greater

display of negative affect might cause their mothers to use milder disciplinary responses. According to this reasoning,

because male infants are more likely to cry, whimper, etc. during discipline events, their mothers use longer vocalizations

and more affectionate terms to prevent or shorten these displays of negative affect. It is easy to see how, as infants pass the

12-month mark, mothers’ responses could change. Maternal patience could wear out as the children approach the “terrible

twos,” when rates of misbehavior and externalizing behavior increase tremendously (Arnold, O’Leary, Wolff, & Acker, 1993;

Miner & Clarke-Stewart, 2008). Once rates of child misbehavior and negative affect reach a certain threshold, mothers might

respond with harsher, rather than milder, discipline techniques. Such a dynamic reversal of dyadic behavior ought to be

detectable as a phase transition between a stable attractor for the mother–son dyad during year one to a different (and more

negative) attractor appearing during at some point after 12 months of development (Hollenstein, 2007).

4.4. Limitations, contributions, and further study

Our findings on gender differences could stem from elements of the discipline interactions that this study did not suffi-

ciently examine, such as infant misbehavior type. Inferential statistics were not performed on the infant misbehavior type

codes due to the relatively small numbers of misbehaviors in each category. An examination of the descriptive statistics

suggests that some gender and age-based misbehavior type differences might be important topics for future studies. For

instance, boys seemed to have a higher percentage of “harm to mother” misbehaviors across all ages.

The type of physical interventions that took place during discipline events might also be important. Physical intervention

type (i.e. moving the infant, removing object from infant, etc.) was initially part of the Coding System, but results from this

code were not analyzed because we found the physical intervention code to be too dependent on infant misbehavior type

to be meaningfully examined without the infant misbehavior type information. (For instance, toy removal was only coded if

the infant was misusing an object or playing with a forbidden object, whereas moving the infant’s body was usually coded if

the infant was in a forbidden location.) Possibly, mothers of males used more forceful physical interventions than mothers

of females, and the use of physical interventions contributed to male infants’ higher levels of negative affect.

Finally, our findings should not be over-generalized. Participating dyadswere Rhode Islanders from white, predominantly

middle-class backgrounds. Due to the substantial body of literature demonstrating cross-cultural and class differences in

discipline practices (Bernstein, Harris, Long, Iida, & Hans, 2005), it cannot be assumed that our results would hold true for all

segments of the American population or for other national groupings. Furthermore, the original videotaping was done about

20 years ago, andit is entirely possible that disciplinarypractices have changed in that time period. Culturally andhistorically,

parental practices are a moving target. Nevertheless, we have outlined a method that could be used in comparative studies

and have shown the importance of studying discipline in infancy.

4.5. Conclusion

By employing a longitudinal, naturalistic, observation-based approach to the study of young infants we have contributed

new findings to the body of literature on discipline. We have found significant age-based and gender-based differences in

discipline patterns. The most notable results were that during discipline interactions, male infants displayed significantly

more negative emotions than female infants and mothers of male infants used significantly longer vocalizations, and more

affectionate terms, than mothers of female infants. The overall patterns seemed to suggest higher child difficulty in male

infants, and milder discipline usage amongst mothers of male infants.

Usinga methodologythat investigates the details of dyadic discipline interactions longitudinally and cross modally allows

us to address the sources of gender differences in these interactions. None of the significant results of this study would have

been discovered if surveys had been used instead of observations. Dynamic systems theory argues that small changes, or

pushes in one direction, become magnified with the passage of time. Small increases in male infant negative affect, for

instance, could lead to excessively harsh or lax maternal discipline practices (Lorber & Slep, 2005), causing increasingly

problematic discipline patterns as boys grow older. The study of how mothers discipline their infants has tremendous

potential to illuminate the causes of later gender differences in externalizing and aggressive behavior, as well as potential

avenues for interventions. It may be easier to encourage healthy discipline practices in mothers when their infants are young,

and the rates of discipline events are low.

Acknowledgement

We would like to thank and acknowledge the assistance of Ms. Christelle Ngnoumen, Dr. Deborah Schooler and Dr. Jihyun

Sung.


11/11


Appendix A. Supplementary data

Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/

j.infbeh.2013.01.005.

References

Arnold, D. S.,O’Leary, S. G.,Wolff, L. S.,& Acker,M. M. (1993). The ParentingScale:A measure of dysfunctionalparenting in discipline situations.Psychological

Assessment: 5., (2), 137–144.Belsky, J., Woodworth, S., & Crnic, K. (1996). Trouble in the second year: Three questions about family interaction.Child Development: 67., (2), 556–578.Bernstein, V. J., Harris, E. J., Long, C. W., Iida, E., & Hans, S. L. (2005). Issues in the multi-cultural assessment of parent–child interaction: An exploratory

study from the starting early starting smart collaboration. Journal of Applied Developmental Psychology: 26., (3), 241–275.Casas, J. F., Weigel, S. M., Crick, N. R., Ostrov, J. M., Woods, K. E., Yeh, E. A. J., et al. (2006). Early parenting and children’s relational and physical aggression

in the preschool and home contexts. Journal of Applied Developmental Psychology: 27., (3), 209–227.Fausto-Sterling, A., GarcíaColl,C., & Lamarre, M. (2012). Sexing the baby: Part 1 – Whatdo we really know about sexdifferentiation in thefirst year of life?

Social Science andMedicine: 74., (11), 1684–1692.Granic, I., Hollenstein, T., Dishion, T. J., & Patterson, G. R. (2003). Longitudinal analysis of flexibility and reorganization in early adolescence: A dynamic

systems study of family interactions. Developmental Psychology: 39., (3), 606–617.Grusec, J. E., & Goodnow, J. J. (1994). Impact of parental discipline methods on the child’s internalization of values: A reconceptualization of current points

of view. Developmental Psychology: 30., (1), 4–19.Hendrix, R. R. (2004). Emergence of parental prohibition in response to self-produced locomotion and its accompanying emotional changes. Lincoln: University

of Nebraska.Hollenstein, T. (2007). State Space Grids: Analyzing dynamics across development. International Journal of BehavioralDevelopment: 31., 384–396.Hollenstein, T., Granic, I., Stoolmiller, M., & Snyder, J. (2004). Rigidity in parent–child interactions and the development of externalizing and internalizing

behavior in early childhood. Journal of Abnormal Child Psychology: 32., (6), 595–607.

Kawabata, Y., Alink, L. R. A., Tseng, W.-L., van Ijzendoorn, M. H., & Crick, N. R. (2011). Maternal and paternal parenting styles associated with relationalaggression in children and adolescents: A conceptual analysis and meta-analytic review.Developmental Review: 31., (4), 240–278.

Kochanska, G. (2001). Emotional development in children with different attachment histories: The first three years. Child Development: 72., (2), 474–490.Kochanska, G., Aksan, N., & Nichols, K. E. (2003). Maternal power assertion in discipline and moral discourse contexts: Commonalities, differences, and

implications for children’s moral conduct and cognition. Developmental Psychology: 39., (6), 949–963.Kochanska, G., Coy, K. C., & Murray, K. T. (2001). The development of self-regulation in the first four years of life. Child Development: 72., (4), 1091–1111.Kochanska, G., Coy, K. C., Tjebkes, T. L., & Husarek, S. J. (1998). Individual differences in emotionality in infancy. Child Development: 69., (2), 375–390.Kochanska, G., Kuczynski, L., & Radke-Yarrow, M. (1989). Correspondence between mothers’ self-reported and observed child-rearing practices. Child

Development: 60., (1), 56–63.Kochanska, G., Tjebkes, T. L., & Forman, D. R. (1998). Children’s emerging regulation of conduct: Restraint, compliance, and internalizationfrom infancy to

the second year.Child Development: 69., (5), 1378–1389.Laumann, E. O., Michael, R. T., & Gagnon, J. H. (1994). A political history of the national sex survey of adults. Family Planning Perspectives: 26., (1), 34–38.Lorber, M. F., & Slep, A.M. (2005). Mothers’ emotion dynamics and their relations with harsh and lax discipline: Microsocial time series analyses. Journal of

Clinical Child andAdolescent Psychology: TheOfficial Journal for the Societyof Clinical Child andAdolescent Psychology, American Psychological Association,Division53: 34., (3), 559–568.

Lytton, H., & Romney,D. M. (1991). Parents’ differential socialization of boys and girls: A meta-analysis. Psychological Bulletin: 109., (2), 267–296.McFadyen-Ketchum, S. A., Bates, J. E., Dodge, K. A., & Pettit, G. S. (1996). Patterns of change in early childhood aggressive–disruptive behavior: Gender

differences in predictions from early coercive and affectionate mother–child interactions. Child Development: 67., (5), 2417–2433.Miner, J. L., & Clarke-Stewart, K. A. (2008). Trajectories of externalizing behavior from age 2 to age 9: Relations with gender, temperament, ethnicity,

parenting, and rater. Developmental Psychology: 44., (3), 771–786.Nelson, D. A., Hart, C. H., Yang, C., Olsen, J. A., & Jin, S. (2006). Aversive parenting in China: Associations with child physical and relational aggression. Child

Development: 77., (3), 554–572.Ostrov, J. M., & Keating, C. F. (2004). Gender differences in preschool aggression during free play and structured interactions: An observational study. Social

Development: 13., (2), 255–277.Pallant, J. (2007). SPSS Survival Manual. England: Open University Press.Pfiffner, L. J., & O’Leary, S. G. (1989). Effectsof maternaldisciplineand nurturance on toddler’sbehavior andaffect. Journal of Abnormal Child Psychology: 17.,

(5), 527–540.Power,T. G.,& Chapieski, M. L. (1986). Childrearing andimpulsecontrolin toddlers:A naturalisticinvestigation.DevelopmentalPsychology: 22., (2),271–275.Ravn, I. H., Smith, L., Lindemann, R., Smeby, N. A., Kyno, N. M., Bunch, E. H., et al. (2011). Effect of early intervention on social interaction between mothers

and preterm infants at 12 months of age: A randomized controlled trial. Infant Behavior and Development: 34., (2), 215–225.Ravn, I. H., Smith, L., Smeby, N. A., Kynoe, N. M., Sandvik, L., Bunch, E. H., et al. (2012). Effects of early mother–infant intervention on outcomes in mothers

and moderately and late preterm infants at age 1 year: A randomized controlled trial. Infant Behavior andDevelopment: 35., (1), 36–47.Regalado, M., Sareen, H., Inkelas, M., Wissow, L. S., & Halfon, N. (2004). Parents’ discipline of young children: Results from the National Survey of Early

Childhood Health. Pediatrics: 113., (6 Suppl.), 1952–1958.

Seifer, R., Sameroff, A. J., Barrett, L. C., & Krafchuk, E. (1994). Infant temperament measured by multiple observations, mother report. Child Development:65., 1478–1490.

Socolar, R. R., Savage, E., Keyes-Elstein, L., & Evans, H. (2005). Factors that affect parental disciplinary practices of children aged 12 to 19 months. SouthernMedical Journal: 98., (12), 1181–1191.

Straus, M. A., Hamby, S. L., Finkelhor, D., Moore, D. W., & Runyan, D. (1998). Identification of child maltreatment with the Parent-Child Conflict TacticsScales: Development and psychometric data for a national sample of American parents. Child Abuse andNeglect: 22., (4), 249–270.

van Zeijl, J., Mesman, J., Stolk, M. N., Alink, L. R., van Ijzendoorn, M. H., Bakermans-Kranenburg, M. J., et al. (2007). Differential susceptibility to discipline:The moderating effect of child temperament on the association between maternal discipline and early childhood externalizing problems. Journal of Family Psychology: JFP: Journal of the Division of Family Psychology of the American Psychological Association: 21., (4), 626–636.

Wissow, L. S. (2002). Child discipline in the first three years of life. In N. Halfon, K. T. McLearn, & M. A. Schuster (Eds.), Child rearing in America: Challenges facing parents with young (pp. 146–177). Cambridge: Cambridge University Press.
http://dx.doi.org/10.1016/j.infbeh.2013.01.005http://dx.doi.org/10.1016/j.infbeh.2013.01.005http://dx.doi.org/10.1016/j.infbeh.2013.01.005http://dx.doi.org/10.1016/j.infbeh.2013.01.005

Documents

Gender and Discipline in 5-12 Month Old Infants