The Happiness of Babies...philosophy of good life, but in contemporary ‘happiness research’ the more limited meaning is focused on. The Journal of Happiness Studies describes its

The Happiness of Babies

A Research Synthesis

Ida Schultz, student of Cognitive Science (B.Sc.) at Universität Osnabrück, Germany

Paper prepared in the context of a research internship at Erasmus University Rotterdam, Erasmus

Happiness Economics Research Organization, September – December 2013

Supervisor: Prof. Dr. Ruut Veenhoven

ABSTRACT:

We want our infants to be happy. But how happy are they and what determines their level of

happiness? In this paper, I first list the questions we want to be answered. Next, I take stock of

the available research findings on the happiness of babies. This research is based on observation

of behaviors deemed to be indicative of mood level such as crying or laughing. I found 15 such

studies which together cover 1708 infants in five countries. The findings are gathered in the

World Database of Happiness, 54 distributional findings on how happy babies are and 927

findings on co-variants of babies’ happiness.

These data suggest that the average mood level of babies tends to be around 6 on a scale

0-10, which is slightly lower than the common level among adults. Variations around this

average level are partly due to ‘nature’, a comparison of twins suggests a heritability of up to

50%. ‘Nurture’ factors are, for example stimulation by mother (positive) and depression of

mother (negative). Surprisingly, breastfeeding is negatively correlated with the baby’s

happiness. The infant’s good mood appears to encourage active and positive behavior on the

part of the caregiver. The few longitudinal data show no correlation between mood in infancy

and happiness in adolescence.

So far, the data provide answers to some of my initial questions, but most of them still

remain open.

1. INTRODUCTION

Are our babies happy? There is already much known about the happiness of adolescents, adults

and elderly persons. The World Database of Happiness contains some 20.000 research findings on

how happy these people are (distributional findings) and on what correlates with more or less

happiness (correlational findings). But how about the youngest earth-dwellers aged from zero to

three years? Do they experience something like ‘happiness’? If so, how happy are they and how

happy can they realistically be? What determines the infant’s happiness? And finally, what

consequences does early happiness have for the life as an adolescent and adult?

In this paper, I examine the stock of the research findings on the happiness of infants and

toddlers that are collected up to now in the World Database of Happiness (Veenhoven, 2014b).

The World Database of Happiness is a web based archive of research findings on subjective

enjoyment of life kept at Erasmus University Rotterdam in the Netherlands. Findings are sorted

by subjects, methods and populations and one of the populations distinguished is ‘babies’.

As a start, I consider what we would like to know about the happiness of babies. Next, I

asses what we do know and list the findings by question. I close with an overview of what we do

not know yet and point out which questions still have to be answered in the future.

2. WHAT WE WANT TO KNOW

Why bother about the happiness of babies? Simply, it is because we want our youngest to be

happy. Parents want to know how to provide their little one’s a happy start in life and the issue is

also of interest for wider society where the aim of greater happiness for a greater number of

people is rising on the political agenda. This aim of promoting the happiness of babies and

infants requires answers to the following questions.

2.1 Does the concept of happiness apply to babies?

The most basic question is whether the concept of happiness also applies to infants and not

exclusively to adults, adolescents and older children. Can infants aged between zero and three

years enjoy life?

2.2 If so, can we assess infant’s happiness?

If the concept of happiness indeed applies to babies, we have to consider whether we are able to

measure the infants’ happiness. If this is not the case, we can only speculate about the happiness

of babies.

2.3 If so, how happy are infants?

Further, in the case that we are able to measure happiness at the first three years of life, it would

be interesting to know how happy our infants actually are. Do they reach the same level of

happiness as adults? Or are they even happier?

2.4 Determinants - Why aren’t all infants equally happy?

Now, when we can assess how happy infants are, we will probably recognize that they are not all

equally happy. If so, the question arises where these differences originate from. Do they merely

reflect different environmental conditions, such that we can assume that all infants could be

equally happy if they lived in the same environment? Or is it rather a matter of innate

temperament such that not every infant has the possibility of reaching the same level of

happiness even if we changed the environment at the best? According to these two options, the

determinants can be divided into the main subareas: nature and nurture.

2.4.1 Impact of nature

At first we want to have a look at the innate determinants defining each individual’s happiness.

How do our genes determine our happiness? Is happiness heritable?

Are normal infants happier than handicapped infants? Or is it the other way round?

2.4.2 Impact of nurture

The other subgroup of determinants of infant happiness is the nurture. The import of nurture can

be sub-divided into two different parts: unswayable determinants and actively influenceable

determinants. These are considered in more detail in the following steps.

Determinants we can hardly control

Some aspects of the nurture cannot be influenced very well. In that context, the following

questions come to mind.

How do the circumstances of pregnancy and birth influence the infant’s happiness?

Does the month or season of birth have an impact on the infant’s happiness?

For example, are summer-born infants happier than winter-borns?

To which extend does the culture the baby is born in and the culture the parents belong

to influence the happiness of the baby?

Determinants on which we have some control

What can we actively do to have happy infants and toddlers? This is probably the most

interesting question for parents and society. Can research give us advice?

Who has the happier baby? Young parents in their twenties or older parents in their

thirties and forties?

What about the parent’s happiness and the marital satisfaction? Do happier couples have

happier babies? Do happier people raise happier offspring (disregarding the heritability)?

What influenceable circumstances mold the baby’s happiness during pregnancy (e.g.

smoking, wanting the child, listening to a special kind of music)?

To which extend does our unconscious, intuitive behavior affect our offspring’s

happiness? Or is it in turn influenced by her/his happiness?

Does a certain parental behavior lead to a happier infant?

Do parent’s reception of and satisfaction with support by family, friends and community

affect the baby’s happiness?

Are happier babies and infants treated differently in comparison with less happy infants?

Are babies with the mother as primary caregiver happier than babies primarily taken care

of by the father?

2.5 Should we aim at happier babies?

Happiness of the offspring in her/his first three years is evidently desirable, both for the offspring

and for her/his parents. But is there more value in happiness than feeling good? Are there further

consequences of babies being happy or not?

Happiness has been shown to protect physical health in adults (Veenhoven, 2008). Does

happiness also keep infants healthier?

Do happier infants also lead a happier life as an adolescent and adult?

The answers to these questions require first of all a definition of happiness, which we will

provide below in section 3.

3. CONCEPT OF HAPPINESS

The word ‘happiness’ has several meanings. In the broadest sense it denotes everything that is

good about life and is synonymous with ‘quality of life’ or ‘well-being’. A more constricted

meaning is subjective enjoyment of life. The broad meaning of happiness dominates in classical

philosophy of good life, but in contemporary ‘happiness research’ the more limited meaning is

focused on. The Journal of Happiness Studies describes its scope as ‘the subjective appreciation

of one’s life as a whole’ and this definition is also taken as basis for the World Database of

Happiness. For these purposes happiness is synonymous with ‘life-satisfaction’. In this study, I

also focus on this limited meaning of the word and in fact, narrow to one of its particular aspect.

When assessing how much people like their life, they use two sources of information: 1)

how well they feel most of the time and 2) to what extent they perceive their aims to be reached.

Veenhoven (1984, Chapter 2) refers to these sub-evaluations as ‘components’ of happiness,

respectively an ‘affective’ component, which he calls hedonic level of affect, and a ‘cognitive’

component, which he refers to by the notion contentment. This conceptualization is presented in

Figure 1.

Figure 1: Concept of Happiness

The concepts of ‘overall happiness’ and ‘contentment’ cannot be applied to the youngest

of us, since babies and toddlers do not yet have the cognitive skills to contemplate their lives.

They are not able to reflect their aims by taking into account the past and the future in order to

rate to which degree they are satisfied with their aims to be achieved. But, even in the case that

we were wrong about their cognitive skills, still they are not capable of reporting their points of

view.

However, babies can be in a good or bad mood such that the component of hedonic level

of affect seems to be more promising concerning the infant’s happiness. Their general level of

hedonic tone, thus pleasantness during experiencing life can indeed be noticed. Though, they are

not able to report their hedonic level themselves, this component can be externally monitored.

Pleasantness usually is accompanied by observable bodily actions like smiling, laughing, and

happy vocalization. Hence, external observers can make estimates about how the babies’ feel

inwardly.

4. MEASURES OF HEDONIC LEVEL OF AFFECT IN BABIES

In older children, adolescents and adults, hedonic level of affect is usually measured using self-

reports, typically with answers to questions about how well one feels most of the time

(retrospective assessment) as well as repeated answers to questions concerning how one feels

right now (experience sampling). Infants are not aware of their mood, and certainly not aware of

how they feel most of the time. Even if they had this awareness, they were still not able to

answer questions. Fortunately, hedonic level can also be inferred from non-verbal behaviors,

such as smiling and laughing.

Babies smile very early in life such that it cannot be a result of imitation (Freedman,

1964). They do not smile or laugh to hide their true feelings like adults who smile to be kind and

accepted even when they do not feel very well. Instead, the infant’s smile seems rather to be an

unconscious reaction indicating pleasure. Hence, in order to assess the infant’s positive mood,

we can observe the frequency of their smiling and laughing and compare with the frequency of

negative affect, typically crying.

Observations are often made by the parents, typically mothers, who estimate the baby’s

typical mood. Sometimes, independent, trained examiners observe the baby in the laboratory or

at home to assess her/his hedonic level. Usually, across different situations and time points, it is

clocked how often and for how long the baby smiles or laughs and the intensity is rated.

Such observations are usually rated by means of different standardized questionnaires,

which typically cover a wider range of behavioral tendencies, referred to as ’temperament’.

Examples for such questionnaires are the Infant Temperament Questionnaire (ITQ). by Carey

(1970) or the Infant Behavior Questionnaire (IBQ) by Rothbart (1981). A (nearly) complete list

of questionnaires is presented at Table 1.

In the next sections, I first describe the two main types of observational assessment in

more detail. Subsequently, I discuss their advantages and disadvantages and report how these

measures are classified in the collection ‘Measures of happiness’ of the World Database of

Happiness.

4.1 Observation by caregiver

Caregivers, normally one of or both parents, can be asked to rate either the baby’s typical mood

or to rate the typical mood in specific situations. In the latter case these ratings are aggregated to

an average level. A common question reads: “During the last week, how often did your baby

smile, when given a toy?” with a verbal rating scale from “never” to “always”. Such questions

can be posed in a face-to-face interview with parents or presented on a written questionnaire. The

rating can be executed by interviewing the parents or by letting them fill in a questionnaire and

such data gathering can take place at home or at a different place.

4.2 Observation by examiner

The observation by an examiner can be undertaken at home or in a laboratory setting. Usually

this is conducted at a point of time, when the infant has just slept and eaten, such that these

factors do not bias her/his behavior. Trained examiners rate the infant’s smile and laughter while

observing her/him in different situations. Normally, the behavior is videotaped to be rated

afterwards. Observations may include global ratings and time sampling. There exist several

methods each providing a consistent instrument of assessment of infant temperament including

infant happiness, e.g. the Bayley Test (Bayley, 1969). Further instruments are listed in Table 1.

4.3 Observation schedule

Babies mood is mostly assessed using an observation schedule which contains a set of instructions

for the observer on how to rate manifestations of the baby’s happiness. For example, it contains

questions for the mother concerning the baby’s general behavior providing special answering

options. Questions are e.g. “When waking up: a) generally happy (smiling, etc), b) variable moods

at these times, c) generally fusses on waking up and going to sleep” (Carey Parent Questionnaire

on Infant Behavior). Likewise, instructions for an external examiner involve ratings for different

situations, e.g. the baby’s smiling during a 5-minute period on a scale from 1 to 5. An item in the

Infant Behavior Record (IBR)reads for example: “rating of infant’s behavior on basis of

videotaped behavior: “General emotional tone”: 1 extremely upset, crying vigorously 2 between 3

upset but can be soothed 4 5 bland, no apparent reaction 6 7 contented, happy 8 9 exited or

animated” (Bayley, 1969).

Such observation schedules help to avoid selectivity in the observations and ratings. To

guarantee the reliability of the gathered data, often two or more trained examiners rate the same

infants’ behavior and intercorrelations are computed. The higher the correlation the more reliable

the data are.

The two types of observational assessment introduced above (observation by caregiver

and by examiner) seem to be the only available options to measure infant’s happiness. Still, we

have to be careful with their interpretation. Let us have a look at the advantages and

disadvantages of these types of measurement.

4.4 Strengths and weaknesses of the methods

The parental questionnaire seems to be able to give a more precise description of the offspring’s

temperament than the rating by an examiner, because the parents spend most of the day with

their infant and therefore know exactly how s/he behaves in different situations and they know

which behavior is normal and which behavior is only a single event. The parents are the ones

who are able to rate their infant’s overall mood on basis of days, weeks and months. But the

parent’s rating is a very subjective measure such that we have to wonder what it actually

measures. Since parents cannot compare their child to the average, we do not know the criterions

they take into account for rating their infant as happy or not. The data might not be comparable.

Furthermore, it is well shown that mothers and fathers rate their child’s behavior differently

(Goldsmith & Campos, 1990; Gartstein & Rothbart. 2003). Fathers tended to evaluate activity as

positive emotionality whereas mothers tended to rate it as negative emotionality. The difference

in mothers and fathers rating probably base upon general gender differences but also on

difference amounts of time spent with the offspring at different points of time as already reported

Rothbart (1981). Thus, we have to ask, whether parental report really assesses the infant’s

general mood or whether it rather assesses the parental perception of the latter.

The observation and rating by an examiner is probably the more objective method, since

several trained raters who are not emotionally related to the child rate her/his behavior on a

common basis. They exclusively assess the infant’s temperament including her/his mood, i.e.

duration, intensity and amount of smiling or general pleasure. But their possibilities are limited

since the child is only observed for some hours during one or a few meetings. Even if these

meetings take place at a point of time when the infant is fed and has slept such that her/his mood

should not be biased by her/his unsatisfied basic needs. Anyway, the results might not reflect the

infant’s general temperament and mood, albeit they provide the more objective data.

4.5 Context of measurements of infants’ happiness

The above described measures of infant mood have been developed in the context of research on

‘temperament’, which is the genetic component of personality, where personality is a tendency to

react in a particular way. Babies are suitable subjects for identifying such innate dispositions

since their reactions are not yet much influenced by learning.

In the 1950s and the 1960s, Alexander Thomas, Stella Chess and Herbert G. Birch1

(Thomas et al., 1960, 1963; Chess et al., 1960) found that differences in temperament already

occur in very early childhood. They defined nine basic temperament traits: activity level,

rhythmicity, approach or withdrawal, adaptability, intensity of reaction, threshold of

responsiveness, distractibility, attention span and persistence and quality of mood. Most

researchers used these nine characteristics to introduce methods to measure the infant’s

temperament. For our aim, mainly the category mood is of interest, since it can be an indicator of

hedonic level which -as already explained above- is the only available type of happiness

assessable in infants.

4.6 Classification in the World Database of Happiness

The World Database of Happines comprises i.a. a collection of ‘Measures of Happiness’ which

involves all acceptable indicators of happiness as defined in section 3 of this paper. These

measures are classified by 1) conceptual focus (variants shown in figure 1), 2) time frame of the

observation, 3) method of observation and 4) rating of observation.

The measures of infant hedonic level at hand here are classified in focus category ‘A’ (for

Affect). Within the category further sub-classifications are as “Affect: Affect Balance” (A-AB)

1 Their New York Longitudinal Study started in the year 1956, including 141 children.

or “Affect: Cheerful Appearance” (A-CA) or “Affect: Cheerful Person” (A-CP). As time

reference usually the “last week” (cw) or the “last day” (md) or the “present” (c) is used. Since

the mode of assessment is observation by others it is coded for example by “rating by family”

(rdf) or rather the systematic observation is coded by “rating by interviewer (of happy

appearance)” (ri) or “time sampling of happy behaviors” (tsb). At last, the rating scale is coded,

e.g. “verbal scale” (v) or “numerical scale” (n). Hence, the coding of a measure of infants’

happiness may look like “A-CP-mi-tsb-n-7a”. Each measure has a unique coding.

In the following part, I present the results of the studies that have used these measures.

5. WHAT WE DO KNOW

Results of the research synthesis

Infants’ happiness was assessed in fifteen studies. These studies are marked with * in the list of

references of this paper. In the Bibliography of Happiness, they are listed in subject section

‘Happiness in Infants’ (code Ak01.01.01). These studies involved 1708 infants and their parents

(mostly mothers) in the United States, Canada, Japan, Israel and the United Kingdom. Together

these studies yield 980 findings of which 54 findings are on how happy babies are (distributional

findings) and 926 findings are about determinants of more or less happiness of babies

(correlational findings).

5.1 How happy are infants?

At first, we wanted to know how happy our infants can be and how happy they typically feel. In

order to be able to compare the given means which are result of different assessments, we

aligned all the mean scores to the same 11-step happiness scale from 0 to 10, which are presented

in Figure 1.

Figure 1: Infants’ Average Happiness on 11-step-scale computed by WDH team

The averages range from 0 to more than 8 and a mean of 5,86 on a scale from 0 to 10. This

average score is slightly lower in comparison with the adults’ average hedonic level, which lies

at 6,71 for the United States (Veenhoven, 2014a). No difference appears in the variance in mood

among infants and adults. Babies’ happiness increases with age, which might be related to the

cognitive development.

These averages of infant happiness as computed by the WDH team2 should not be taken

for granted. Comparability is hampered by differences in rating scales largely, modes of

assessment and the number of assessed infants. Details are reported in Table 2.

5.2 Determinants of babies’ happiness

Why are not all infants equally happy? Correlational findings suggest some answers to that

question.

5.2.1 The impact of nature

A few studies provide a view on inborn determinants of happiness.

Heritability

Emde et al. (1992), Plomin et al. (1993) and Robinson, Emde & Corley (2001) compared

happiness in twins, both monozygotic and dizygotic. On that basis, they report that even in the

14-months-olds an impact of genes of up to 50% on the hedonic tone can be found

Inborn handicaps

Rozga et al. (2010) studied infants who were later at the age of three years diagnosed with

autism. Since autistic people’s impairment consists of a loss of comprehension of social

interaction, Rozga and his colleagues expected to find these differences at the age of six months

in infants who were later diagnosed with autism. They assumed that the autistic baby would

smile less than the normal one since the act of smiling at that age is mostly an unconscious

answer to social interaction indicating pleasure. Surprisingly, they didn’t find a difference in

smiling and showing pleasure between the infants later diagnosed with autism and the healthy

ones.

5.2.2 The Impact of nurture

What about environmental correlates of infants’ mood? All the available research findings are

about parental behavior.

Breastfeeding

Blandine de Lauzon-Guillain and her colleagues (2012) inspected whether at the age of three

months, formula-fed babies are less happy compared to mixed-fed or breast-fed babies. Contrary

to expectations, the breast-fed offspring appeared to be slightly less happy than the formula-fed.

2 World Database of Happiness Team

They were also rated lower concerning emotional stability. This finding does not fit observed

positive effects of breast-feeding on infantile cognitive development (Morrow-Tlucak, Haude &

Ernhart, 1988; Kramer et al., 2008).

Stimulation by mother

In an Israeli study, Pnina S. Klein (1984) compared the mothers rating of her baby to her

behavior towards her/him. It turned out, that happy infants received more sensory and social

stimulation from the mother. Yet, of course the direction of influence cannot be determined.

Caudill and Weinstein (1969) observed American and Japanese mothers and their babies

in home situations. The American babies were more active and expressed happy vocalization to a

greater extent than the Japanese babies who rather tended to be passive and occasional unhappy

vocalization. The authors explained these outcomes in terms of the different cultural concepts of

the baby. In America a baby has to be brought up to become an independent individual such that

the mother talks a lot to the child. In Japan a baby is a distinct being that has to be integrated in

the community such that the mother rather lulls and rocks it instead of talking to her/him.

Mother’s depression

Whiffen and Gotlib (1989) asked depressed and non-depressed mothers to rate their two months

aged infant’s temperament and subsequently let independent observers rate the baby’ emotional

tone. The babies of the depressed mothers were significantly less happy than the healthy

mothers’ babies and even showed negative emotions more frequently, albeit there was no

difference in the mothers’ ratings of the infants’ difficulty of temperaments. Thus, either the

baby suffers from the mother’s depression or the mother suffers from the baby’s negative

emotionality.

5.3 Consequences of babies’ happiness

Everybody likes happy babies and every parent wants her/his infant feel well. But what

consequences follow from the infant’s happiness except for satisfying the parents? Is early

happiness a guarantor for later happiness? Does happiness stimulate development?

Effects on parental behavior

Above we have seen that happy babies receive more stimulation. Next to an effect of stimulation

of the babies’ happiness, this correlation could occur due to an effect of babies happiness on

parental behavior: happy babies my elicit more attention from their parents. Empirical research

has not yet separated these causal effects. Still there is a clue in a study on adoption preferences.

Volk and Quinsey (2002) presented parents and non-parents with images of babies and

asked to rate their willingness to (fictionally) adopt each of these. Afterwards, they also rated the

infant’s happiness. Happy looking babies were more likely to be selected for adoption, at leastby

women. No difference was found among men.

Effects on later happiness

(Schaefer & Bayley, 1963) compared behavioral manifestations of good moof in the first year of

life with a clinical rating of happiness in adolescence and found little correlation. If not due to

methodological problems this could mean both modest genetic determination of happiness and

little effect of early happiness.

An overview of all the studies and their findings is presented in Table 3 which is appended.

5.4 How to have a happy baby

What can we learn from these findings? It was shown that the infant’s well-being depends to a

certain degree on innate temperament. For parents, this information can help to relax because

they are not fully responsible for having an unhappy infant.

Also interesting for parents is the finding of breast feeding, which counters common

wisdom and thus is a relief for mothers who opted for bottle feeding. Yet, we are not sure about

the correlation’s direction. Are less happy babies more likely to be breast-fed than others or does

the breastfeeding lead to a decrease of the baby’s emotional stability? Probably, if we would

exclusively consider the baby’s the smaller amount of happiness related to breastfeeding, the

mother’s should rather switch to formula-feeding. But I think this is not an option regarding the

cognitive development which is a fact supported by a lot of research.

Even more important is the observed correlation if the parent’s mental health with the

baby’s happiness. This should be acknowledged in the decision to have children or not, together

with research findings on the negative effect of having children on the happiness of parents, and

of mentally vulnerable parents in particular (Veenhoven, 2014c, 2014d). A policy implication is

that protection of children requires investment in mental health care for parents.

The findings on stimulation imply that it is very important to spend time with the infant,

even when s/he is still very young and does not yet seem to react to it. This conclusion is

supported by the findings of Goldsmith & Campos (1996). Infants seem to be happier in

interaction with persons they know very well which might also origin from the familiar person’s

knowledge of what the baby likes because she spend more time with her/him. Hence, parents

should spend more time with their offspring. For the government, from this it follows that part-

time-jobs should be provided to a larger amount for women and for men such that they have

more time to spend with their child, which in turn positively influences her/his happiness.

Goldsmith and Campos’ (1996) findings, concerning the different parental perceptions of

infants’ temperament might be interesting for the respecting parents. That is to say that they

should talk about how they perceive their offspring and about their worries. Probably they have

different views such that they can appease and support each other. This might help to not worry

about non-existing problems.

6. WHAT WE DO NOT YET KNOW

The findings reported above in section 5do not answer all the questions raised in section 3 of this

paper.

As yet, research tells us little about circumstances of pregnancy and delivery that

influence the baby’s happiness. For instance, no data about listening to a certain kind of music or

eating special food during pregnancy have been reported. Furthermore, the aspect of innate

disability was concerned regarding autism, but there are a lot of other disabilities like the Down’s

syndrome or physical disabilities whose influence on the infant’s well-being would be interesting

for future parents.

For those, who plan to have children, it might be an important fact to know whether

summer-born babies are happier, hence the season of birth can be actively influenced to support

the offspring's well-being.

Research found relations between the parents' behavior and their baby's happiness. But,

these data are mostly based on observations of mother-child-interactions. Nowadays, fathers

spend much more time with their offspring than at the early years of this research area which

most of the presented studies were conducted in. We do not know whether fathers have a

different influence on the baby's happiness or whether babies are happier when the mother is

their primary caregiver or whether this privilege is reserved for the fathers. Data dealing with this

issue might simplify decisions for parents about who will stay at home and who will go to work.

The impact of the parents' age is not explicitly reported but in the database we can find

those parents, who are older at the child's birth are generally happier. Probably, they do not feel

that overstretched by the large responsibility than younger parents. Thus, if we could say, that

happier parents have happier babies, we could conclude that older parents have the happier

babies. But parents' happiness was not measured in relation to the infants' well-being.

One of our questions asked for cultural differences. This question was addressed by

Caudill and Weinstein in the year 1969. But this study is limited to a comparison between the

American and the Japanese culture. Additionally, we do not know whether their findings also

apply to the actual globalized world of the year 2013.

Lastly, the database does not provide data concerning the most important question: Will

happier babies lead a happier life as an adult? If there would be no correlation then, why should

we aim at having happy babies?

7. CONCLUSION

How happy our babies are can be measured using observation techniques. The available research

findings suggest that the concept of happiness also applies to the youngest earth-dwellers and

that they mostly feel better than neutral. But, on average their happiness is slightly lower than

among adults. Happiness of babies is influenced by inborn dispositions and environmental

conditions, in particular the by parental behavior. The study of infant happiness is still in its

infancy.

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temperament." Child Development (1984): 1212-1218.

16 Kramer, Michael S., et al. "Breastfeeding and child cognitive development: new evidence

from a large randomized trial." Archives of general psychiatry 65.5 (2008): 578.

17 Lauzon-Guillain, Bd, et al. "Breastfeeding and infant temperament at age three months."

PloS one 7.1 (2012): e29326.

18 Matheny, Adam P., and Ronald S. Wilson. “Developmental tasks and rating scales for the

laboratory assessment of infant temperament”, American Psycholog. Ass., Journal Suppl.

Abstract Service, 1981.

19 Medoff-Cooper, Barbara, William B. Carey, and Sean C. McDevitt. "The early infancy

temperament questionnaire." Journal of Developmental & Behavioral Pediatrics 14.4

(1993): 230-235.

20 Morrow-Tlucak, Mary, Richard H. Haude, and Claire B. Ernhart. "Breastfeeding and

cognitive development in the first 2 years of life." Social Science & Medicine 26.6 (1988):

635-639.

21 Plomin, Robert, et al. "Genetic change and continuity from fourteen to twenty months: The

MacArthur Longitudinal Twin Study." Child development 64.5 (1993): 1354-1376.

22 Putnam, Samuel P., Maria A. Gartstein, and Mary K. Rothbart. "Measurement of fine-

grained aspects of toddler temperament: The Early Childhood Behavior Questionnaire."

Infant Behavior and Development 29.3 (2006): 386-401.

23 Ramey, Craig T., and Dale C. Farran. "The functional concern of mothers for their infants."

Infant Mental Health Journal 2.1 (1981): 48-55.

24 Robinson, J. L., Emde, R. N., & Corley, R. P. (2001). Dispositional cheerfulness: Early

genetic and environmental influences. In R. N. Emde & J. K. Hewitt (Eds.). Infancy to early

childhood: Genetic and environmental influences on developmental change (pp. 163-177).

London: Oxford University Press.

25 Rothbart, Mary Klevjord. "Measurement of temperament in infancy." Child Development

(1981): 569-578.

26 Rozga, Agata, et al. "Behavioral profiles of affected and unaffected siblings of children with

autism: Contribution of measures of mother–infant interaction and nonverbal

communication." Journal of autism and developmental disorders 41.3 (2011): 287-301.

27 Schaefer, Earl S., and Nancy Bayley. "Maternal behavior, child behavior, and their

intercorrelations from infancy through adolescence." Monographs of the Society for

Research in Child Development 28.3 (1963): 1-127.

28 Schanberg, Saul M., and Tiffany M. Field. "Sensory deprivation stress and supplemental

stimulation in the rat pup and preterm human neonate." Child development (1987): 1431-

1447.

29 Thomas, Alexander, et al. "A longitudinal study of primary reaction patterns in children."

Comprehensive Psychiatry 1.2 (1960): 103-112.

30 Thomas, A., Chess, S., et al. “Behavioral individuality in early childhood”, New York: New

York University Press (1963).

31 Veenhoven, R. "Conditions of Happiness (Reidel, Dordrecht)." (1984).

32 R. Veenhoven, (2014a) World Database of Happiness, collection Happiness in Nations,

Overview of happiness surveys using Measure type: 222 / 10-item Affect Balance Scale

(Bradburn), viewed on 2014-03-25 at

http://worlddatabaseofhappiness.eur.nl/hap_nat/nat_fp.php?mode=7

33 Veenhoven, R., (2014b) Bibliography of Happiness (section of ‘Happiness in age-groups’),

World Database of Happiness, Erasmus University Rotterdam, Assessed on 2013-12-20 at:

http://www1.eur.nl/fsw/happiness/hap_pub/list_stud.php?popid=55

34 Veenhoven, R. (2014c) Findings on Happiness and Children:Having, World Database of

Happiness, Erasmus University Rotterdam, The Netherlands, Assessed on 2014-03-25 at:

http://www1.eur.nl/fsw/happiness/hap_cor/top_sub.php?code=C3

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http://www1.eur.nl/fsw/happiness/hap_cor/top_sub.php?code=M7

36 Volk, Anthony, and Vernon L. Quinsey. "The influence of infant facial cues on adoption

preferences." Human Nature 13.4 (2002): 437-455.

37 Whiffen, Valerie E., and Ian H. Gotlib. "Infants of postpartum depressed mothers:

temperament and cognitive status." Journal of abnormal psychology 98.3 (1989): 274.

16

Table 1: Observation Methods Used for Assessment of Infants’ Happiness

Name of Method Happiness

Measure

Rating scale Classification in

World Database of

Happiness

Author

Questionnaires

1 IBR Infant Behavior Record

(part of Bayley Infant Behavior

Profile)

General emotional tone 1 to 9 A-CA-mi-tsb-v-8a

A-CA-mi-tsb-v-9a

A-CA-mi-tsb-v-9b

Bayley, 1969

(paper n.a.)

not in DB

2 ITQ [Carey] Infant Temperament

Questionnaire

Mood 0 to 2

(originally: high to low)

A-CA-g-rdf-v-3-a Carey, 1970

3 R-ITQ Revised Infant Temperament

Questionnaire

Mood 1 to 6

(originally: high to low)

Carey & McDevitt, 1978

not in DB

4 ICQ Infant Characteristics Questionnaire

General Mood 1 to 7 A-CA-g-rdf-v-7b Bates, Bennett Freeland &

Lounsbury, 1979 Smiles and happy

sounds

1 to 7 A-CA-g-rdf-v-7a

5 IBQ Infant Behavior Questionnaire

Smiling and laughter 1 to 7 A-CA-cw-rdf-v-7a Rothbart, 1981

6 TTS Toddler Temperament Scale

Quality of mood 1 to 3

(originally high to low)

Fullard, McDevitt & Carey,

1985

not in DB

7 EITQ Early Infancy Temperament

Questionnaire

Mood 1 to 6 Medoff-Cooper, Carey,

McDevitt, 1993

not in DB

8 TBAQ Toddler Behavior Assessment

Questionnaire

Pleasure 1 to 7 Goldsmith, 1996 (paper of

1987 not available)

not in DB

17

9 ECBQ Early Childhood Behavior

Questionnaire

High Intensity Pleasure 1 to 7 Putnam, Gartstein &

Rothbart, 2006 Low Intensity Pleasure 1 to 7

not in DB

10 IBQ-R Revised Infant Behavior

Questionnaire

High Intensity Pleasure 1 to 7 A-CA-cw-rdf-v-7-ab Gartstein & Rothbart, 2003

Smiling & Laughter 1 to 7 A-CA-cw-rdf-v-7-b

Low Intensity Pleasure 1 to 7 A-CA-cw-rdf-v-7-ba

Observation schedules used in laboratory assessment

1 Bayley test General emotional tone Bayley, 1969

(paper n.a.)

not in DB

2 LTS Laboratory Assessment of Infant

Temperament

Emotional Tone

(during assessment &

physical measurement)

1 to 9 Matheney & Wilson, 1981

(paper n.a.)

1 to 9

not in DB

3 LAB-TAB Laboratory Temperament

Assessment Battery

Joy/ pleasure Goldsmith & Rothbart, 1991

not in DB

4 General assessment method of

Infants Temperament

Total positive Garcia Coll, Halpern, Vohr,

Seifer, Oh, 1992

not in DB

18

Table 2: Happiness of Babies: Averages observed in 13 studies transformed to scale 0-10

Subjects/ Location Assessment/Measure Average

mood on

scale 0-10

Author/Year

Examiners’ ratings of infants’ happiness in laboratory settings

"Louisville Twin Study",

12 months aged twins,

N=84 (18 male-male pairs, 16 female-female pairs, 8

opposite-sex pairs);

Kentucky, USA

changed Infant Behavior Record 1981, Matheney & Wilson (paper

n.a.) Emotional Tone during assessment

(videotaped) 4.13

Emotional Tone during physical measurement 4.63

not in DB

6-18 months aged infants & their mothers,

N=24;

USA

Infant Behavior Record 1981, Ramey & Farran

Infant's happiness 5.84

2 months aged babies & their 25 depressed mothers, 25 non-

depressed mothers,

N=50;

Ontario, Canada

Bayley assessment in lab 1989, Whiffen & Gotlib

infant's observed happy emotional tone 5.2

14 months aged, 199 same-sex twin pairs,

N= 398;

Colorado, USA

rating instrument not reported 1992, Emde et al.

positive hedonic tone 4.4

overall mood 6.25

14 & 20 months aged, 199 same-sex twin pairs,

N=398;

Colorado, USA

no special rating instrument 1993, Plomin et al.

positive hedonic tone 4.47

overall mood 6.42

19

14, 20 & 24 months aged, 100 MZ twin pairs,

100 DZ twin pairs,

N=400;

Colorado, USA

rated with Hedonic Tone Scale (Easterbrook&Emde, 1983, unpublished!)

2001, Robinson, Emde & Corley

positive hedonic tone (1-4 scale) 4.53 14 months: 4.4

20 months: 4.57

24 months: 4.6

Parents’ rating of infant's average happiness in daily life

4-8 months aged infants & their mothers,

N=206;

Philadelphia, USA

Revised Infant Temperament Questionnaire 1978, Carey & McDevitt

infant's mood 4.34

not in DB

6 & 12 months aged infants (born in 1980, first-born) & their

mothers,

N=40;

Petach Tikva, Israel

Infant Temperament Questionnaire 1984, Klein

Infant's mood 6.85

12-36 months aged children and their caregivers,

N=309,

Philadelphia, USA

Toddler Temperament Scale 1985, Fullard, McDevitt & Carey

Infant's mood 0.35 1st year: 0.2

2nd year: 0.5 not in DB

14-24 months aged infants & their mothers,

(Sample 6&7: 18-24 months, N=102;

Sample 10: 14-21 months, N=81;

Sample 11: 18 months, N=78)

N=261;

Wisconsin, USA

Toddler Behavior Assessment Questionnaire 1996, Goldsmith

(1987 paper n.a.) Smiling & Laughter/ Pleasure 6.6

not in DB

6-12 months aged infants (3 age groups: 3-6, 6-9, 9-12

months) & their parents,

N=361;

Oregon, USA

Revised Infant Behavior Questionnaire 2003, Gartstein & Rothbart

High Intensity Pleasure 8.27 Group 1: 7.78

Group 2: 8.38

Group 3: 8.58

20

Low Intensity Pleasure 6.8 Group 1: 7.20

Group 2: 6.78

Group 3: 6.40

18 (n=104), 24 (n=99), 30 (n=98), and 36 (n =94) months

aged infants & their parents;

N=395 (94 different infants);

mid-coast Maine, USA

Early Childhood Behavior Questionnaire 2006, Putnam, Gartstein, Rothbart

High Intensity Pleasure 6.63 18 months: 6.32

24 months: 6.58

30 months: 6.9

36 months: 6.78

Low Intensity Pleasure 6.52

18 months: 6.53

24 months: 6.58

30 months: 6.47

36 months: 6.48 not in DB

3 months aged infants (born 2006-2009) & mothers;

Breast-fed (BF, N=137) vs. formula-fed (FF, N=88) vs.

Mixed-fed (MF, N=91) infants;

N=316;

Cambridge, UK

Revised Infant Behavior Questionnaire 2012, Lauzon-Guillain et al.

High Pleasure 6.85 FF: 7.33

MF: 6.67

BF: 6.67

Smiling & Laughter 5.85

FF: 6.33

MF: 5.67

BF: 5.67

Low Pleasure 6.85

FF: 7.17

MF: 6.83

BF: 6.67

21

Table 3: Happiness of Babies: Overview of Correlates and Number of Findings

Correlate with happiness Observed relation with happiness In studies (number

in reference list)

Detail in table 4

Positive

(≥+.10 effect size)

Unrelated

(-.10 to +.10 effect size)

Negative

(≤-.10 effect size)

Characteristics of baby

Age 6 24 17

Health 2 36 25

Monozygotic twins 16 1 1 8, 21, 24 15, 16, 17

Dizygotic twins 11 7 8, 21, 24 15, 16, 17

Heritability 14 5 8, 21, 24 15, 16, 17

Common environment 9 9 1 8, 21, 24 15, 16, 17

Correlation from 14 to 20 months 3 21 16

Resemblance 2 36 25

Approach 3 12 13

Cuteness 2 36 25

Vocal Reactivity 3 12 13

High Intensity Pleasure 2 12 13

Smiling/Laughter 2 12 13

Activity Level 4 3 12, 13, 25 13, 24, 7

Perceptual Sensitivity 3 12 13

Sadness 1 2 12 13

Distress to Limitations 1 1 5 12,13, 25 13, 24, 7

22

Fear 1 2 4 12, 13, 25 13, 24, 7

Falling Reactivity 2 1 12 13

Low Intensity Pleasure 2 12 13

Cuddliness 2 1 12 13

Duration of Orienting 7 12, 13, 25 13, 24, 7

Soothability 7 12, 13, 25 13, 24, 7

Empathy 3 24 17

Prohibition 3 24 17

Responsive to persons 4 10 18 27 20

Rapid 8 16 8 27 20

Active 14 15 3 27 20

Not shy 32 27 20

Positive Behavior 32 27 20

Calm 32 27 20

Friendly/ Friendliness 19 7 2 27 20

Cooperative/ Cooperativeness 27 20

Attentive/ Attentiveness 27 20

Facility 27 20

Laughter 1 13 24

Instrumental attempts 2 13 24

Joy/Pleasure 1 13 24

Later Characteristics of Child

Friendly/ Friendliness 27 20

23

Cooperative/ Cooperativeness 27 20

Attentive/ Attentiveness 27 20

Facility 27 20

Not shy 34 11 3 27 20

Interested 9 5 2 27 20

Exerts Effort 7 8 1 27 20

Not distractible 11 4 1 27 20

Systematic 11 4 1 27 20

Swift comprehension 11 2 3 27 20

Valid Test 15 1 27 20

Inactive 4 4 27 20

Timid 2 1 5 27 20

Courteous 3 3 2 27 20

Tactful 2 2 27 20

Social 3 3 2 27 20

Independent 6 2 27 20

Bold 2 4 2 27 20

Irritable 5 3 27 20

Rude 2 2 27 20

Hostile 7 1 27 20

Cold 1 1 2 27 20

Reserved 4 2 2 27 20

Conscientious 2 2 27 20

24

Defiant 1 3 27 20

Sulky 1 3 27 20

Discontented 4 27 20

Gloomy 4 27 20

Popular 1 2 1 27 20

Characteristics of Caregiver

IBQ scale loadings for first

common factor (maternal/paternal

report)

2 13 24

Correlation Laboratory observation

& IBQ report

5 1 13 24

Present Behavior of Caregiver

Adoption Preference 1 1 36 25

Tactile Stimulation 2 15 22

Kinesthetic Stimulation 1 1 15 22

Visual Stimulation 2 15 22

Auditory Stimulation 1 1 15 22

Mediation by affect 2 15 22

Mediation by smile 2 15 22

Mediation by play 1 1 15 22

Instrumental mediation 2 15 22

Verbal mediation 2 15 22

Contingency : Positive Vocal 2 15 22

25

Contingency: Distress 2 15 22

Object Environment Responsivity 2 15 22

Object Environment Complexity 1 1 15 22

Object Environment Variety 2 15 22

Functional Maternal Concern Index 2 23

Walking Fingers(mom, smile) 6 13 24

Walking Fingers(exp., smile) 5 13 24

Walking Fingers(mom, laugh) 4 13 24

Walking Fingers(exp., laugh) 3 13 24

Peek-a-boo (mom, smile) 11 13 24

Peek-a-boo (exp., smile) 10 13 24

Peek-a-boo (mom, laugh) 9 13 24

Peek-a-boo (exp., laugh) 7 1 13 24

Walking Finger instrumental 2 13 24

Autonomy 4 2 2 27 20

Ignoring 2 6 27 20

Punitiveness 1 7 27 20

Perceives Child as Burden 2 8 27 20

Strictness 1 7 27 20

Use Fear to Control 8 27 20

Punishment 1 7 27 20

Irritability 8 27 20

Anxiety 1 1 6 27 20

26

Intrusiveness 1 3 4 27 20

Concern about Health 5 3 27 20

Achievement Demand 4 1 3 27 20

Excessive Contact 2 3 3 27 20

Fostering Dependency 3 1 4 27 20

Emotional Involvement 4 4 27 20

Expression of Affection 7 1 27 20

Equalitarianism 8 27 20

Positive Evaluation 8 27 20

Rejection of Homemaking 1 3 4 27 20

Negative Emotionality 1 7 27 20

Mood Swings 8 27 20

Financial Stress 1 7 27 20

Poor Physical Health 4 4 27 20

Suppression of Aggression 1 7 27 20

Dominance 4 4 27 20

Self-Abasement 4 4 27 20

Dependency 3 1 4 27 20

Over-Conscientiousness 4 2 2 27 20

Sociability 5 2 1 27 20

Cooperativeness 6 2 27 20

Estimated Intelligence 7 1 27 20

Narcissism 4 4 27 20

27

Later Behavior of Caregiver (mother)

Ignoring 8 27 20

Punitiveness 3 5 27 20

Irritability 2 6 27 20

Perceives Child as Burden 1 2 5 27 20

Use Fear to Control 1 2 5 27 20

Strictness 2 4 2 27 20

Wish to Control Child 5 3 27 20

Social Isolation of Child 4 1 3 27 20

Intrusiveness 3 2 3 27 20

Excessive Contact 4 4 27 20

Fostering Dependency 5 1 2 27 20

Achievement Demand 7 1 27 20

Emotional Involvement 6 2 27 20

Positive Evaluation of Child 7 1 27 20

Expression of Affection 5 2 1 27 20

Equalitarianism 5 3 27 20

Positive Mother-Child Relationship 7 1 27 20

Autonomy 2 2 4 27 20

Rejection of Homemaking Role 1 1 6 27 20

Anxiety of Mother 1 4 3 27 20

Dependency 4 4 27 20

Sociability 6 2 27 20

28

Cooperativeness 8 27 20

Emotional Withdrawal 3 4 1 27 20

Marital Happiness 1 6 1 27 20

Estimated Intelligence 6 1 1 27 20

Positive Emotional State 4 1 3 27 20

Communicativeness 3 5 27 20

Summed up: 660 274 318

29

Table 4: Correlates of Babies’ Happiness: Overview of selected Finding

FINDINGS * p<.10, ** p<.05, ***p<.01, ****p<.001

Subjects/ Location Assessment of happiness Observed correlation

with happiness

Verbal summary Author

Methods for measuring infant hedonic level

1 The New York

Longitudinal Study

(NYLS)

observation, interview with

parents

Indication of 9 infant & child temperament scales:

activity, rhythmicity, approach, adaptability, intensity,

MOOD, persistence, distractibility, threshold;

distribution into 3 subgroups: "easy children", "slow to

warm up", "difficult children"

1956 ff., Thomas,

Chess & Birch

Mood

not in DB

2 “The McArthur

Longitudinal Twin Study”

(MALT)

observation at home, examiner

filled in IBR afterwards

/ Infant Behavior Record (IBR) in Bayley-Setting vs. IBR

in non-Bayley-Setting

1969, Bayley

(paper n.a.)

General emotional tone/ degree

of Happiness (1-9 scale)

/

not in DB

3 4-8 months aged infants &

their mothers,

N=101;

Philadelphia, USA

ITQ completed by mother [Carey] Infant Temperament Questionnaire (ITQ)

a good index for measuring Infant Behavior

1970, Carey

Infant's mood (0-2 scale: 0=high,

1=moderate, 2=low)

+

4 4-8 months aged infants &

their mothers,

N=206;

Philadelphia, USA

parents filled in RITQ Revised ITQ (RITQ):

(standardized only for the 4 to 8 month range), better

because more items and more answer-options, not

sufficient by itself

1978, Carey &

McDevitt Mood (1-6 scale) (1=low,

6=high), [order revised by WDH team!]

M=3.17

not in DB

5 4-6 months aged infants

and their mothers,

N=322;

Indiana, USA

mother filled in ICQ, home

observation

Infant Characteristics Questionnaire (ICQ) 1979, Bates,

Bennett Freeland

& Lounsbury General Mood (1-7 scale) /

Smiles and happy sounds

(1-7 scale)

/

not in DB

30

6 "Louisville Twin Study",

12 months aged twins,

N=84 (18 male-male pairs,

16 female-female pairs, 8

opposite-sex pairs);

Kentucky, USA

observation of videotaped

behavior in lab, rating on basis of

a changed IBR

Laboratory Assessment of Infant Temperament (LTS):

general assessment method (videotaped assessment of

emotional tone, physical measures of emotional tone)

1981, Matheney

& Wilson (paper

n.a.)

Emotional Tone (1-9 scale)

during assessment (videotaped)

M=4.3

Emotional Tone (1-9 scale)

during physical measurement

M=4.7

not in DB

7 3-12 aged infants & their

parents,

N= 463;

Oregon, USA

IBQ filled in by parents Infant Behavior Questionnaire (IBQ): showing

reliability; parents' reports about the same child are

similar, but not alike because they spent time with child

at different moments

1981, Rothbart

Infant's smiling and laughter /

8 12-36 months aged

children and their

caregivers,

N=309,

Philadelphia, USA

parents filled in TTS Toddler Temperament Scale (TTS): Assessing

Temperament of 1-3 year old children

1985, Fullard,

McDevitt &

Carey Quality of mood (1-3 scale) [order revised by WDH team!]

1-year olds: M=0.04

Gender: r=+.12 ns

Age: r=+.18 **

2-year old: M=0.10

Gender: r=-.08 ns

Age: r=+.01 ns not in DB

9 3-18 months aged infants,

Oregon, USA

observation of videotaped

behavior in lab (LAB-TAB)

The Laboratory Temperament Assessment Battery (LAB-

TAB): giving a standard laboratory setting to asssess

infants temperament; 20 settings, 4 per dimension; locomotor version for 12 & 18

months old infants, prolocomotor version for 6 months old

infants;

1991, Goldsmith

& Rothbart

Joy/ pleasure (LAB-TAB)

Smiling & Laughter (IBQ) stability increases with age

Activity level:

6 months: r=+11

12 months: r=+.00

Fear:

6 months: r=-.22

12 months: r=-.34

31

Distress to Limitations:

6 months: r=-.19

12 months: r=-.30

Soothability:6 months:

r=+.2912 months: r=+.17

Duration of Orienting:

6 months: r=+.19

12 months: r=+.19

Pleasure (TBAQ) social desirability: r=+.45

activity level: r=+19

social fearfulness: r=-.21

anger proneness: r=+.19

interest/persistence: r=+.32 not in DB

10 3 & 7 months aged,

preterm & full-term

infants,

N=79 at 3 months, N=73

at 7 months;

Rhode Island, USA

special assessment method (lab) general assessment method of Infants Temperament at 3

& 7 months of age

1992,Garcia Coll,

Halpern, Vohr,

Seifer, Oh Total positive /

Sociability: positive response during

several 'social' situations

Preterm:

3 months: M=7.91

7 months: M=11.11

Full-term:

3 months: M=11.49

7 months: M=15.61 not in DB

11 1-4 months aged infants &

their parent,

N=404;

Philadelphia, USA

EITQ Early Infancy Temperament Questionnaire (EITQ),

RITQ for infants younger than 4 months

1993, Medoff-

Cooper, Carey,

McDevitt infant's mood (1-6 scale) ?

not in DB

12 14-24 months aged infants Parent filled in TBAQ Toddler Behavior Assessment Questionnaire (TBAQ), 1996, Goldsmith

32

& their mothers

(Sample 6&7: 18-24

months, N=102;

Sample 10: 14-21 months,

N=81;

Sample 11: 18 months,

N=78),

N=261;

Wisconsin, USA

Smiling & Laughter/ Pleasure (1-

7 scale)

Sample 6&7:

M=5.07Sample 10:

M=4.90Sample 11

M=4.87overall: M=4.96

16-36 months, comparison TBAQ - IBQ (1987 paper not

available)

not in DB

13 3-12 months aged infants

(3 age groups: 3-6, 6-9, 9-

12 months) & their

parents,

N=361;

Oregon, USA

parents filled in R-IBQ Reliability of Revised Infant Behavior Questionnaire (R-

IBQ):

more differentiated measure of infant temperament,

satisfying reliability of subscales, mother & father

similar ratings but not alike (probably because they

spent time with infant at different points of time,

IBQ-R as unique opportunity of rating infant's

temperament because parents answer questionnaire

2003, Gartstein &

Rothbart High Intensity Pleasure (1-7

scale)

Group 1: M=5.67 ***

Group 2: M=6.03 ***

Group 3: M=6.15 ***

males: M=6.03 ***

females: M=5.86 ***

Smiling & Laughter (1-7scale) no significant effects

Low Intensity Pleasure (1-7

scale)

Group 1: M=5.32 ***

Group 2: M=5.07 ***

Group 3: M=4.84 ***

14 18 (n=104), 24 (n=99), 30

(n=98), and 36 (n=94)

months aged infants &

their parents;

N=395 (94 different

infants);

Maine, USA

primary caregiver filled in ECBQ Early Childhood Behavior Questionnaire (ECBQ):

18-36 months

2006, Putnam,

Gartstein &

Rothbart

High Intensity Pleasure (1-7

scale)

18 months: M=4.79

24 months: M=4.95

30 months: M=5.14

36 months: M=5.07

Low Intensity Pleasure (1-7

scale)

18 months: M=4.92

24 months: M=4.95

30 months: M=4.88

36 months: M=4.89 not in DB

33

Correlates of infant happiness: happiness of siblings

15 14 months aged, same-sex

twin pairs (199 pairs),N=

398;Colorado, USA

observation of infant at home,

2weeks later in lab, Bayley &

free play

showing that heritability influences only on positive

emotionality whereas earlier studies often show genetic

influences only for negative emotionality

1992, Emde et al.

positive hedonic tone (1-4

scale)

h²= + ns

c²= + ns

overall mood (1-7 scale) h²= + ns

c²= - ns

16 14 & 20 months aged same-

sex twin pairs (199 pairs),

N=398;

Colorado, USA

behavioral observation, Bayley

& free play

genetic factors are large responsible for continuity from

14 to 20 months;

disputable: generalisability, computation of h² and c²

1993, Plomin et

al.

positive hedonic tone (time

sampling)

14 months: h²: + ns

c²: + ns

20 months: h²: + ns

c²: + ns

CHANGE: h²= + **

c²= 0 ns

Continuity: h²= + ns

c²= + ns

overall mood (1-7 scale) 14 months: h²: + ns

c²: 0 ns

20 months: h²: + ns

c²: + ns

CHANGE: h²= + ns

c²= 0 ns

Continuity: h²= + **

c²= + ns

34

17 14, 20 & 24 months aged,

100 MZ twin pairs,

100 DZ twin pairs,

N=400;

Colorado, USA

observation in home & lab,

rating with Hedonic Tone

Scale (Easterbrook&Emde, 1983,

unpublished!)

at 20 months: strongest genetic influence on positive

expressiveness in Bayley & free play, but not great at 14

& 24 months;

shared environment influenced continuity over time and

consistency across contexts

2001, Robinson,

Emde & Corley

positive hedonic tone (1-4

scale)

14 months: M=2.32

20 months: M=2.37

24 months: M=2.38

MZ: + ***DZ: + (*** at

14&20 months,** at 24

months)

Heritability:

+.22 ns (14months)

+.40 ** (20months)

+.16 ns (24months)

Common environment:

+.28 ns (14months)

+.14 ns (20months)

+.10 ns (24months)

Empathy (pos. expr.):

+ ***

Prohibition (pos. expr.):

+ ***

18 6-18 months aged infants,

N=83;

California, USA

observation in lab surprising finding: infants diagnosed autism at 36

months, did not smile less toward caregiver at 6 months,

they were also equally sensitive to disruption of

contingent social interaction

2010, Rozga et al.

Positive Affect

Correlates of infant happiness: feeding mode

19 3 months aged infants (born

2006-2009) & mothers;

mothers indicated feeding-

mode & they filled in R-IBQ

"breast-fed & mixed-fed babies were rated as having

lower impulsivity, positive response to stimulation,

2012, Lauzon-

Guillain et al.

35

Breast-fed (=BF, N=137)

vs. Formula-fed (=FF,

N=88) vs. Mixed-fed (=MF,

N=91) infants;

N=316;

Cambridge, UK

High Pleasure (1-7 scale) FF: M=5.4

MF: M=5.0

BF: M=5.0

lower ability to regulate own emotions, higher emotional

instability"

Smiling & Laughter (1-7 scale) FF: M=4.8

MF: M=4.4

BF: M=4.4

Low Pleasure (1-7 scale) FF: M=5.3

MF: M=5.1

BF: M=5.0

Affect Balance (computed by

WDH team)

FF: 7.1

MF: 5.7

BF: 5.4

Correlates of infant happiness: perception of temperament & related behavior

20 0-36 months aged infants

(born in 1928-29) & their

mothers,

N=54;

California, USA

maternal behavior observed in

lab

boys: positive behavior & happiness at 27-36 months

positivly correlated with attentiveness & facility between

27 & 96 month

girls:positive behavior & happiness not predictive of

positive behavior at distant ages;

1963, Schaefer &

Bayley

infant's happiness (1-7 scale)

infant's positive behavior

21 6-18 months aged infants &

their mothers,

N=24;

USA

home & lab, examiner filled in

IBR for infant and HOME for

mother

Functional Maternal Concern (Maternal Warmth and Verbal

Responsivity, Absence of Restriction & Punishment, Maternal Involvement with the Child)

1981, Ramey &

Farran

Infant's happiness Functional Maternal

Concern: + **

M=5.67

22 6 & 12 months aged infants

(born in 1980, first-born) &

their mothers,

N=40;

at home, observation of

mother's behavior, mothers

completed ITQ

Infants rated as more adaptable, approaching, intense in

response and positive in mood received more sensory

and social stimulation.

1984, Klein

Infant's mood (0-2 scale) rated expressed pos. affect: + ns

36

Petach Tikva, Israel by mother (only girls)

visual stimulation: + ***

(only girls)

object environment chosen

by mother: +

23 2 months aged babies and

their depressed mothers

(N=25)/ non-depressed

mothers (N=25),

N=50;

Ontario, Canada

Bayley assessment in lab,

questionnaires (NPI, ICQ)

Infants of depressed mothers significantly less happy

(also more rapidly showing negative emotion);

depressed mothers did not rate their infants as more

termperamentally difficult

1989, Whiffen &

Gotlib

infant's observed happy

emotional tone (1-9 scale)

depressed mothers:

M=4.76non-depressed

mothers: M=5.56

(significant differences)

24 9 months aged infants &

their parents,

140 twins, 28 singletons,

N=168 ;

Denver, USA

observation in lab, each parent

completed IBQ

more smiling, laughter&instrumental acts in situations

with mother than with familiar experimenter;

Mothers and fathers perceive their infant's behavior

differently.

Fathers are more likely to rate infant's activity as

positive emotionality, mothers more often rate this as

negative emotionality.

1990, Goldsmith

& Campos

Smiling: latency, peak

intensity & duration

Peek-mom: ++++ **

Peek-exp.: +++ **

WF-mom: ++ **

WF-exp.: + **

Laughter: latency, peak

intensity & duration

Peek-mom: +++ **

Peek-exp.: +++ **

WF-mom: + **

WF-exp.: ++ **

Joy/ instrumental; + **

Joy/pleasure (broad) + **

concord maternal IBQ with lab

observation

smiling: +.23

laughter: +.11

instrumental act: +.17

concord paternal IBQ with lab

observation

smiling: +.19

laughter: +.02

instrumental act: +.29

37

Correlates of infant happiness: happiness rated by stranger, correlated adoption preferences

25 Adults (having children,

not-having children)

(21 videos of 4-6 months

aged infant faces),

N=152 ;

Ontario, Canada

rating of pictures of infants in

lab concerning willingness to

adopt, health, happiness,

resemblance & cuteness

for women baby's happiness, health and cuteness are

more important than resemblance; for men it is the other

way round!

2002, Volk &

Quinsey

adults rated the infants' (shown

in video) happiness

women: +.208 ***

men: +.089 ***

Correlates of infant happiness: cultural differences

26 30 Japanese, 30 American

first born infants aged 3-4

months and their mothers,

N=60;

Tokyo & Kyoto, Japan;

Washington D.C., USA

observation at home (during

1961-64)

American baby's: more active &happily vocal (mother

more often looks at and talks to baby)

Japanese baby's: passive with occasional

unhappy vocalization (mother more often lulls, cares

and rocks her baby)

1969, Caudill &

Weinstein

happy vocal (rated by

observer)

Nation: rpc=+.51 ****

Father's occup.: rpc=+.02 ns

Baby's gender: rpc=+.14 ns

unhappy vocal (rated by

observer)

Nation: rpc=-.33 **

Father's occup.: rpc=-.21 ns

Baby's gender: rpc=-.03 ns

Appendix A: Observation Schedule: Carey Parent Questionnaire on Infant Behavior

Rating of babies behaviour by mother on 13 questions

A When waking up

a generally happy (smiling, etc)

b variable moods at these times

c generally fusses on waking up and going to sleep

B With interuptions of milk and solid feedings, as for burping

a is generally happy and smiles

b variable response

c generally cries with these interuptions

C After feeding the baby

a smiles and laughs

b content but not usually happy (smiles etc) or fussy

c fussy and wants to be left alone

D Initial reaction to new foods

a pleasant (smiles, etc) whether accepts or not

b variable or intermediate

c response unpleasant (cries, etc), whether accepts or not

E When diaper is soiled with b.m

a usually fusses

b sometimes fusses

c usually does not fuss

F During diapering and dressing

a generally pleasant (smiles, etc.)

b variable

c generally fusses

G Usual reaction to bath

a laughs and smiles

b variable

c usually cries or fusses

H During produres such as mail cutting, hair brushing, washing face and hair; onece established

a generally pleasant, smiles

b neutral or variable

c generally fussy or crying

I With physical exam by doctor

a generally friendly and smiles

b both smiles and fusses; variable

c fusses most of the time

J With any kind of illness

a much crying and fusing

b variable

c not much crying, just whimpering sometimes, generally his usual self

K Initial reaction to approach by strangers

a positive, friendly (smiles etc)

b variable reaction

c rejection or withdrawal

L General Reaction to familiar people

a friendly, Smiles and laughs

b variable reaction

c generally glum and unfriendly, little smiling

M Initial reaction to new places and situations

a acceptance - tolerates or enjoys thenm in a few minutes

b variable

c rejection, does not tolerate or enjoy in a few minutes