Infants Development

Observational Studies on Infants Development

File photo. The Developmental Stages of a Child (Online Psychology Degree Guide, 2021) Observational studies are studies in which behaviour is observed and recorded, and the researcher does not attempt to influence the individual’s natural behaviour in any way.

1.   Baby biographies

Perhaps the simplest in form is the case study, which involes repeated observations of the same person over time. These observations are usually of infants, and are made by parents or caregivers who are close to the child. These are often called baby diaries, or baby biographies, which may either describe several aspects of development, such as Darwin’s biography described below, or may focus on a more specific type of development, such as emerging musically (Forrester, 2010).

Charles Darwin wrote a delightful biographical sketch of the development of his first born son — William Erasmus Darwin (in Slater & Muir, 1999). William Erasmus (nicknamed ‘Doddy’) was born on 27 December 1839, but Darwin’s account of his development was not published until 1877, by which time Charles and his wife Emma had had another nine children, five boys and four girls (Darwin, 1877/1999): thus Darwin was able to compare his eldest child with his others. we will give four extracts from this account in order to illustrate some of the strengths and weaknesses of such biographies:

• Seeing: ‘With respect to vision, – his eyes were fixed on a candle as early as the 9th day, and up to the 45th day nothing else seemed thus to fix them; but on the 49th day his attention was attracted by a brightly coloured tassel . . .

• Hearing: ‘Although so sensitive to sound in a general way, he was not able even when 124 days easily to recognize whence a sound proceeded, so as to direct his eyes to the source.’
• Anger: ‘When two years and three months old, he became a great adept at throwing books or sticks, etc., at anyone who offended him; and so it was with some of my other sons. On the other hand, I could never see a trace of such an aptitude in my infant daughters; and this makes me think that a tendency to throw objects is inherited by boys.’ (italics added)
• Anger: ‘When two years and three months old, he became a great adept at throwing books or sticks, etc., at anyone who offended him; and so it was with some of my other sons. On the other hand, I could never see a trace of such an aptitude in my infant daughters; and this makes me think that a tendency to throw objects is inherited by boys.’ (italics added)
• Moral Sense: (When 2 years and 7¹/₂ months) ‘I met him coming out of the dining room with his eyes unnaturally bright, and an odd unnatural or affected maner, so that I went into the room to see who was there, and found that he had been taking pounded sugar, which he had been told not to do. As he had never been in any way punished, his odd manner certainly was not due to fear and I suppose it was pleasurable excitement struggling with conscience . . . As this child was educated solely by working on his good feelings, he soon became as truthful, open, and tender, as anyone could desire.’ (italics added)

While such case studies provide a rich source of ideas and insights, they have many obvious weaknesses. Despite the fact that Darwin was one of the finest observers of natural behaviour who has ever lived, we now know that his account of the development of vision and hearing is wrong.

We know from careful experimentation that although vision at birth is poor it is sufficient for the infant to begin learning about the visual world: for instance, within hours from birth infants will prefer to look at their mother’s face when hers is shown paired with that of a female stranger (Bushell, 2003). We also know that newborn infants can localize sounds at birth, an ability that Darwin was unable to detect in his son, even at 124 days (4 months).

We can notice weakness in the italicised extracts from ‘Anger’ and ‘Moral Sense’: in both of these Darwin is expressing untested theoretical views which are derived either from observations of just a few children or from a ‘folk theory of development’ of the sort we discussed earlier. With respect to ‘Anger’, Darwin suggests that there may be inherited gender differences in acts of aggression, and indeed there is clear evidence that the majority of physically aggressive acts are committed by males.

With respect to ‘Moral Sense’, note that Darwin is assuming that children brought up in the absence of physical punishment will display less anti-social behaviour in later life. But it turns out that Darwin was right: that is, the use of punishment is not a good way of changing behaviour, and children disciplined with the use of physical punishment are more likely to misbehave and become aggressive.

The weaknesses of such accounts include problems of generalisation — one or two children hardly constitute a representative sample of the population. Also, the observations tend to be unsystematic, and in many cases are retrospective — that is, events described long after their occurrence.

Baby biographers may have strong theoretical biases which lead them to note anecdotes supporting their own theories.

The strengths of such accounts are primarily two fold:

1. the biographer can give a detailed account of subtle changes in behaviour because of their intimate knowledge of the child;
2. the observations can lead to the production of theories of child development, which can then be given a more systematic (often experimental) test.

2.   Time and event sampling

Time sampling is an observational method in which individuals are studied over a period of time, and at frequent brief intervals during this period a note is made — usually by an observer but sometimes by the individuals themselves — of whether or not certain behaviours of interests are occurring. For example, a researcher might watch a child over a 20-minute play period, noting every 30 seconds for a 5-second interval, whether the child is playing alone, playing with others, not playing, being aggressive, and so on.

Here is one study to illustrate the use of this method. Lee and Larson (2000) sampled 56 high school seniors (17 – 18-year-olds) in South Korea and 62 seniors (17-year-olds) in the United States. Each student was studied for one month and was provided with an electronic timer which gave a beep seven times a day at randomly spaced intervals over the period between approximately 7.00 am to 11.30 pm.

Every time the beeper sounded the student was asked to note down (a) what they were doing, and (b) their affect state (i.e. whether they were happy, sad, etc.) as it was just before the beeper sounded. What they found was that the Korean students recorded many more times spent in schoolwork and much less time in other (e.g. recreational) activities than the American students.

We know that academic stress heightens student anxiety levels (Leung et al., 2010) and what Lee and Larson found was that the Korean students experienced many more negative affect states (i.e. they were more depressed) than their American counterparts. This suggests that the Koreans’ ordeal of studying in preparation for the competitive college entrance examinations was causing them considerable distress and depression.

While the greater academic stress experienced by the Korean students clearly has negative consequences, there are positive rewards: in the biggest ever global school rankings published to date, by the Organisation for Economic Cooperation and Development (2015) the top five performers were Asian — Singapore, Hong Kong, South Korea, Japan, Taiwan (the UK and the US were, respectively, 20th and 28th).

The Lee and Larson study, and other time sampling studies, record the participants’ behaviour at frequent intervals over a period of time, and simply note what is happening at each recording period. The aim is to get an idea of how frequently different behaviours occur during the total observation period.

However, there are two interrelated criticisms of time sampling.

• One is that that researcher may not get an accurate record of the amount of time spent in different behaviours — quite simply, many naturally occurring behaviours may not be happening when each behaviour sample is taken!
• The other is that many behaviours of interest may simply not occur, or might be missed, during the period that recording is taking place.

Event sampling is an alternative method that avoids these problems. As the name suggests, in this procedure the researchers actively select the type of event that they want to observe. This event is then recorded, usually throughout its time period (rather than at intervals as would be the case for time sampling) on a continuous basis — for this reason this type of event sampling is also known as continuous sampling, and it is the most common observation method used in child development research.

There are innumerable events that are of interest to child psychologists. The following list, while long, is not exhaustive!

Although these methods look like longitudinal designs their aim is to accumulate data systematically rather than to investigate change over time.

A final point to note is that the baby biographies, referred to earlier, used both time and event sampling procedures, but not in a particularly systematic fashion.

3.   The clinical method

The greatest developmental psychologists of all time, Jean Piaget, studied the development of his three children during their infancy. He kept very detailed records of their development, but instead of simply recording their development, which is typical of the baby biographers, he would note an interesting behaviour and then, in order to understand it better, he varied the task to note any changes in the infant’s response.

This technique, which is a combination of observation and loosely structured experimentation, is known as the clinical method. He also used this method extensively with other children. Here is a brief extract (Piaget, 1954, pp. 177 – 178) to illustrate the procedure – Piaget observed his son Laurent (aged 6 months 22 days) when reaching for objects:

Piaget’s reasonable interpretation of this observation is that when one object is on top of, and hence touching, another object, his infant did not realise that there were two objects. In fact, it was not until he was 10 months old that he:

As we have seen, observational studies are ideal for discovering questions to ask about various phases and aspects of children’s development. Such studies can often lead to answers and theories, and they are often critical in allowing the researcher to generate hypotheses about aspects of development. We need always to remember that the child has a vast repertoire of behaviours that occur in natural settings. We can conclude that observational studies are ideal in studying children’s behaviour and development in its natural context.