The development of executive functions: evidence from behavioural and electrophysiological perspectives

[Truncated abstract] Background: Executive functions are cognitive processes associated with higher-order levels of behaviour. Previous research has suggested that between the ages of 7 and 11 years, executive functions change from a unitary structure, where specific abilities are indistinguishable from each other, to displaying ‘unity and diversity’, where specific executive functions are separate constructs, yet related to each other. During the same developmental period, large-scale neural changes also occur within the brain. This thesis tests the hypothesis that electrophysiological development occurs before, and is related to, the development of behavioural abilities specific to single executive functions. It is further hypothesised that this development of executive functions through mid- to late-childhood may be a sequential process – neural changes occurring during this time are known to affect the amplitude and latency of event-related potential (ERP) peaks, which may then lead to the development of behavioural abilities specific to single executive functions. This process changes the structure of executive functions from unitary to displaying both unity and diversity.