Developmental cognitive neuroscience

Question 1

What are the key processes that occur in neuronal development in the brain?

Answer 1

1. Synaptogensis: Formation of synapses.
2. Neural pruning: Competition among synapses results in retention of active synpases and elimination of inactive synapses (Hebb’s law).
3. Myelination: Development of myelin sheath from oligodentrocytes in CNS to increase speed of conduction.

Question 2

What is the nature of grey matter development after birth?

Answer 2

Increase up to the age of ~5 years followed by steady decline.

Question 3

What is the relationship between changes in white/grey matter thickness and cognitive ability of children?

Answer 3

1. Children with higher IQ scores tend to show higher rate of cortical thickening/thinning throughout development.
2. Children with higher IQ scores tend to reach peak cortical thickness at a later age.

Question 4

What are the different schools of thought concerning development of cognition?

Answer 4

1. Nativism
2. Empiricism

Question 5

What is nativism?

Answer 5

• Cognition is a consequence of series of genetically pre-programmed brain ‘modules’ that each mediate a specific part of cognition.
• These are either obervable at birth or develop as the child matures.
• Key point is that cognitive abilities are intrinsically present at birth.

Question 6

What is empiricism?

Answer 6

• The brain is a blank slate at birth.
• Knowledge is acquired as a consequence of exposure to senosry stimuli throughout life time.
• These different senosry stimuli are connected together in associated networks throughout life and form the basis of cognition.

Question 7

What are the problems with nativism?

Answer 7

Does not provide a mechanistic view of cognitive development and has limited psychological value.

Question 8

What is the problem with empiricism?

Answer 8

Some developmental phenomena cannot be explained by the theory, such as acquisition of language (development of good language skills despite lack of reinforcement from parents).

Question 9

What is constructivism?

Answer 9

• Hybrid between nativism and empiricism.
• Children are born with innate schemas (e.g. reflexes) that are developed and changed by interactions with the external environment.
• When the schemas are no longer sufficient, they are remodelled to accommodate new requirements.

Question 10

What are the stages of development outlined by constructivism?

Answer 10

1. Sensor-motor stage (~0-2)
2. Pre-operational stage (~2-6)
3. Concrete operational stage (~6-12)
4. Formal operation (12-adult)

Question 11

What is the nature of each developmental stage in constructivism?

Answer 11

• Each stage has limited functionality.
• These limits in functionality are overcome by remodelling of the intrinsic schemas as a result of interactions with the enternal environment.

Question 12

What are the characteristics of the sensori-motor stage?

Answer 12

• Egocentricity (self-centred)
• Objects in the world exist because the child is able to interact with them. Once the child is unable to interact with them, representation of object is lost.

Question 13

What are the characteristics of the pre-operational stage?

Answer 13

• Lack of cognitive flexibility.
• Child develops ability to have mental representations of objects in their absence, allowing them to participate in basic problem solving tasks.
• Child only able to focus on single dimensions when problem solving and are unable to consider multiple dimensions.

Question 14

What are the characteristics of the concrete operational stage?

Answer 14

• Cognitive flexibility develops and the child acquires the ability to incorporate multiple dimensions when problem solving.
• Child only able to apply cognitive flexibility to concrete problems (e.g. arithamtic operations) but not more abstract problems (e.g. algebra).

Question 15

What are the characteristics of formal opperational stage?

Answer 15

Development of the ability to solve abstract problems and there are no longer limitations in cognitive abilities.

Question 16

What is object permanence?

Answer 16

Ability to mentally represent an object even when it is absent.

Question 17

What evidence suggests that babies in sensori-motor stage lack object permanence?

Answer 17

1. Babies to not actively search for objects that become occluded after they are exposed to it during this stage.
2. A-not-B error: The baby is presented with ball in well A, and reaches for it in well A. When the ball is put into well B, baby still reached for it in well A.

Question 18

Aside from lack of object permanence, what is an alternative explanation for A-not-B error?

Answer 18

• Babies don’t have well developed parts of the brain like the prefrontal cortex, and so lack executive functions such as behavioural inhibition.
• Even if they know the ball is in well B, they are unable to stop themselves from reaching for it in well A.

Question 19

What is neoconstructivism?

Answer 19

• There are innate proessing biases towards certain stimuli at birth (e.g. faces). These innate processing ‘schemas’ allow for acquisition of certain types of knowledge more easily.
• Acquisition of knowledge allows formation of new cognitive processes throughout life and specialisation of brain areas to carrying out particular cognitive processes.

Question 20

Why is face processing an important part of social cognition?

Answer 20

Understanding the face of others gives clues as to what the cognitive processes in others may be, allowing internal representations of another’s mental state. This is key in social cognition.

Question 21

What is the false-belief task?

Answer 21

1. Children were shown scenarios whereby a character puts an object in location A.
2. The object is then put into location B by another character.
3. Children asked which location the first character would look for the object.

Question 22

What were the results of the false-belief task?

Answer 22

• Children fail to indicate that the character would look for the object in location A instead of location B.
• Explanation for this could be the fact that they lack ability to represent mind of first character in their minds, so that they are unaware of the fact that despite themselves knowing object was placed into location B, the first character doesn’t.

Question 23

What is “Theory of Mind”?

Answer 23

The ability to have internal representation of the mental state of others in one’s own mind.

Question 24

What are the changes that occur in the prefrontal cortex throughout development?

Answer 24

1. Children show greater activation of PFC when required to perform activity requiring behavioural supression. This implies their PFCs are less efficient at inducing behavioural suppression.
2. Slight differences in PFC activity in adolescence compared to adults may be responsible for their egocentricity and lack of regard for future consequences.

Question 25

What is a possible explanation for the general ‘impulsive’ behaviours displayed by adolescence?

Answer 25

Greater activity in the nucleus accumbens and associated reward system.