Social and Cognitive Development in Childhood and Adolescence II Flashcards
considering developmental trajectories in social understanding
In this lecture, we will be considering developmental trajectories in social understanding. While Piaget’s theory has been much criticised by findings suggesting cognitive competencies very much earlier in life than he predicted, some competencies appear to develop over a very long time period. Furthermore, development appears dynamic – a competence appears at one time point, then declines and re-emerges later. Developmental trajectories such as these have the potential to reveal more about the underlying processes and mechanisms supporting development. However, apparent changes in development over time are not easy to interpret.
The ability to infer the mental states of others
The ability to infer the mental states of others has attracted an enormous amount of research and has often yielded conflicting results. In layman’s terms, the ability to infer mental states results from an appreciation that the behaviour of other people is not simply their reactions to external stimuli and instead that most of their behaviour is driven by the contents of their minds - what they know, what they believe, what they desire and so on. This seems like an essential fundamental skill for navigating human interactions and once acquired, mentalising opens up new worlds of opportunity. It brings with it the understanding that others hold repositories of information that you have yet to learn and that are there just for the taking without having to go through the laborious task of learning it by yourself, you can now trick people into believing something that is or isn’t true for your own gain, you can now withhold knowledge in order to avoid punishments from or gain advantages over others and you can now adapt your responses to allow more rapid and effective communication.
False belief tasks
False belief tasks are a measure of children’s ability to understand the mental states of others, because the predictions that we make about the behaviour of others based on reasoning about their false beliefs differ from the predictions that we make if we reason on the basis of current reality. In fact, the philosopher Dennett has argued that successful reasoning about false beliefs is the only convincing evidence for the attribution of mental states to others (Dennett, 1978). This is because a person who acts on the basis of a false belief acts in a way that would not be predicted by the real situation in the world. One of the most frequently-used methods to probe children’s understanding of false belief involves hiding an object at a location (e.g. Sally-Ann task). Then, while the protagonist is absent, the hiding place is changed. Consequently, when the protagonist returns and seeks the object, the rational act is to look in the location at which the protagonist believes the object to be hidden. But this belief of the protagonist is now false – the object is now in a new location. Hence in order to find the object, the protagonist must discover this new location. However, the protagonist will first seek the object at the wrong location. Knowledge of this likely action sequence is thought to provide an index of the ability to understand false beliefs. For a long time, it was believed that children had no understanding of false belief until the age of 3 – 4 years. Passing the false belief task was equated with having a theory of mind. Between the ages of 3 and 4 years, children were thought to acquire a previously-absent representational concept of belief, and to become able to represent the contents of other people’s beliefs (meta-representation).
Criticism on False belief task
However, as so often, experimental procedures to test mentalising abilities can be criticised. The false belief test appears vulnerable to criticisms that it involves many more processes than mentalising, specifically the interaction of limited working memory capacity (knowledge of the earlier displacement) with limited cognitive inhibition of what is most salient to the child (their own knowledge). Russell tested this by designing a “windows” task as a structurally equivalent task to the false belief task. It is set up as a competitive game, where children can learn to trick an adult to opening a box that does not contain a sweet. If they do so, the child gets the sweet but if they point to the baited box, the adult “wins” the sweet. Once they have been trained on the task, they move onto the deception stage where the boxes now have “windows” facing the child. Hence, the child can now see the sweet and must inhibit this highly salient knowledge in order to pick the unbaited box for the adult to open.
Children between 3-4 are unable to perform this task, suggesting that children of this age are unable to inhibit a prepotent response and could account for poor performance on the false belief task. By four years, executive functioning appears to have developed: children this age pass both the false belief task and the Windows task. However, it could still be argued that even though the false belief task is confounded by high executive functioning demands, children below 4 could be competent in the skill of mentalising and their failure is entirely due to the limitations of the false belief task.
Onishi and Baillargeon (2005)
Onishi and Baillargeon (2005) devised a way of testing false belief understanding in 15-month-old infants, using the violation-of-expectation paradigm and a search task. During familiarisation trials, infants watched as a protagonist hid a toy in one of two possible locations (a yellow box or a green box). The openings of the boxes were at 90’ to the infants, so that the infants could not see into the boxes. In the first familiarisation trial, the actor put the toy into the green box. In the next two familiarisation trials, she put her hand into the green box as though to grasp the toy, and rested her hand there. The infants then saw a belief induction trial. In the false belief condition, they watched as the toy moved location into the yellow box out of view of the actor. The infants observed that the actor did not see this move. In the true belief condition, the actor and infant both watched as the toy moved location. A test trial was then given, during which the actor simply placed her hand into one of the boxes. In the false belief condition, infants were expected to look longer when this was the yellow box, as the actor believed that the toy was in the green box. In the true belief condition, infants were expected to look longer when this was the green box, as the actor believed that the toy was in the yellow box. Further conditions checked the analogous predictions when the first hiding place was the yellow box. Onishi and Baillargeon found that the infants indeed looked significantly longer when the box that the actor chose to search was inconsistent with her belief about the toy’s location. They argued that this was evidence for a rudimentary representational theory of mind in infants.
meta-cognition
It is difficult to accept that the violation of expectation procedure is indicative of an early innate module for meta-cognition. Metacognition involves an understanding of and objective stance upon one’s own mental states and knowledge, yet other skills such as episodic memory which require metacognition are not apparent until much later in development. Furthermore, even adolescents find theory of mind tasks difficult. The “director task” asks participants to move an object on a sets of free-standing shelves, some of which are open and some which are closed at the back. In one condition, they need to move the object referred to by a director who stands behind the shelves and participants must represent his viewpoint in order to identify the specific object he refers to. For example, if he says “move the large ball up” and the largest ball the participant can see is on a closed shelf, they must infer that the director means the next largest ball to their own perception. In another condition, there is no director and participants must obey the rule “only move objects on open shelves”. Both children and adolescents show difficulties on this task compared to adults.
Theory of mind abilities therefore seem to follow a protracted developmental trajectory. The same can be said for imitation and face-processing. In imaging studies, functional specialisation for faces appears to extend well into adolescence. In one study, Sherf et al (2007) presented images of faces, buildings and navigation routes (spatial stimuli) and objects. Classic areas were activated for objects (lateral occipital area) and spatial stimuli (parahippocampal place area) in all three age groups, but activation of face areas (fusiform face area, superior temporal sulcus and occipital face area) was observed only in adolescents and adults.
Developmental Cognitive Neuroscience
Recently, a new area of research called Developmental Cognitive Neuroscience (Johnson, 2011) aims to integrate knowledge about cognitive development with knowledge about the development of the brain. Although this area is still in its infancy, increasingly sophisticated measures for measuring brain development in utero, in very young children and into adolescence and adulthood have produced an extraordinary new body of data and raises the possibility of being able to be used to adjudicate amongst theories of cognitive development which have reached an impasse.
For example, cross-sectional and longitudinal studies of have taken structural brain images of children between four years through late childhood, adolescence and into adulthood. These have documented a linear increase in white matter and a linear decrease in grey matter. Grey matter also region-specific chronological changes, each showing a characteristic rise and fall pattern. In frontal areas, the rise reaches a peak in boys at around 11 years and in girls, around 10 years old. In parietal grey matter, the peak is around nine years, slightly earlier for boys than girls. In temporal cortex, the peak is around 13 years for boys and 11 years for girls. In all cases, the peak is followed by a gradual decline.
What might that indicate from a developmental perspective and from a cognitive perspective?
What might that indicate from a developmental perspective and from a cognitive perspective? One interpretation of the rise and fall pattern is that it reflects the emergence of neural processing networks which, over time, become localised in regions of cortex and then become specialised for performing domain specific functions. The rise could indicate the genesis of new synapses, arborisation of dendrites etc. and the fall could be the consequence of neural selection within developing networks where neurones that synapse onto a network which are activated with sufficient frequency are retained while relatively inactive neurones are pruned away. This would increase the overall efficiency of the network by keeping the most responsive neurones and rejecting those that do not add computing power. This view would suggest that cortical and functional specialisation emerges very slowly, as has been observed in the case of face processing and possibly in a future longitudinal study
might be the case of areas of frontal cortex that in adults have been shown to be involved in processing other people’s mental states.
Interactive Specialisation (Johnson 2011)
These ideas are central to a new theoretical perspective called Interactive Specialisation (Johnson 2011) which attempts to explain those phenomena, where some competencies are observed very early in life, followed by a decline and then a very protracted trajectory of further development over childhood and adolescence. Advocates of this theory argue that none of these trajectories can be interpreted by straightforward nativist explanation of a constantly maturing neural module nor can they be easily explained the empiricist perspective which predicts a gradual emergence of a competency over time.
Johnson’s argument is that early competencies are observed because some areas of cortex have what we might call narrow receptive fields that respond to a very narrow set of input with the result that very specific areas of cortex will tend to be activated by very particular stimulus inputs. Other areas of cortex have a much broader receptive field with the result that they are activated by quite a wide range of different types of stimulation. However, regions of cortex are not isolated from one another – there is intense connectivity across the brain. Hence, when areas are activated (either by highly specific stimuli or a broader range), they will be receiving activity from and will themselves be activating other regions of cortex. The challenge of development is to make selective connections across areas that serve a particular function well by competitive interaction - inter-region connectivity. Even if a particular area has a narrow receptive field and responds very specifically (e.g. to faces), it will nonetheless have the potential to become connected to other areas and also to engage other areas within its own processing network. Johnson argues that the response properties of specific cortical areas are thereby altered through these competitive “activity-dependent” interactions with other areas and become more and more optimal and selective for particular types of stimuli.
