Cognition in children with attentional difficulties with particular reference to working memory.

This research investigated cognitive function in children with observed and rated behavioural manifestations associated with inattention, hyperactivity and impulsivity. The aims were firstly to assess whether there were children in mainstream classrooms who displayed these behaviours, and secondly, to assess executive function and working memory in these children compared to a control group. It was anticipated that the findings could provide a basis for the development of a new model to explain cognitive function in children with attentional difficulties.A group of children with attentional difficulties who were part of the normal population but who did have cognitive difficulties in comparison to controls were identified. It was concluded that these children constituted part of a normal continuum of attentional skills and were not diagnosable. Using the working memory model (Baddeley and Hitch, 1974, Baddeley, 2000) the nature of the cognitive difficulties in children with attentional difficulties was established. Specifically it was revealed that children with attentional difficulties had difficulties on spatial working memory tasks but not on visual working memory tasks. Central executive function was initially proposed to explain differences between the groups, however when this explanation was explored the Supervisory Attentional System (Norman and Shallice, 1980) emerged as a better model to explain the data. Limitations of Barkley's (1997) inhibition model were also identified.It was hypothesised that children with attentional difficulties have difficulties associated with 'executive attentional control' mechanisms which impinge on their ability to complete central executive working memory tasks. Existing models were incorporated into a new model to more accurately explain these difficulties.It is intended that these findings will be followed up longitudinally to assess the development of executive attentional control in children with attentional difficulties and to incorporate these findings into a developmental model.