Training and transfer effects of executive functions in preschool children
This study was supported by grants from the Vårdal Foundation and the Swedish Council for Working Life and Social Research to the first author and by grants from the Knut and Alice Wallenberg Foundation and the Bank of Sweden Tercentenary Foundation to the last author. Training program, investigator training, and technical support provided by Cogmed. No funding provided by Cogmed.
Summary
Working memory (WM) – the ability to retain and manipulate information in mind for short periods of time – and inhibition control – the ability to refrain from acting impulsively – are important executive functions that are related to academic achievement and ADHD. As the importance of executive functions has become more widely known, there has been growing interest in whether these functions can be improved with cognitive training. Of particular interest is whether training could enhance these critical skills in young children and thus prevent difficulties in early academic achievement that may have otherwise occurred.
This question was the focus of the study reviewed here. Participants were 63 four to five year olds attending four different preschools in Sweden. Children were randomly assigned to one of four experimental conditions: Working Memory Training (WMT), Inhibitory Control Training (ICT), an active control condition (ACT), and a passive control condition (PCT). These were all normally developing children, none of whom had ADHD or any other known psychiatric diagnosis.
WMT was provided in daily 15 minute sessions over a five-week period. The focus was on training visuo-spatial WM based on research indicating that this is more strongly associated with ADHD than verbal working memory. During training a number of visual stimuli were presented sequentially on the computer screen; children had to remember their location and order and demonstrate this by clicking with the mouse in the correct locations. Task difficulty was manipulated by increasing the number of stimuli that had to be remembered and was adjusted after each trial according to whether the child had answered correctly. This ‘adpative’ training ensured that children were constantly challenged by tasks that were closely suited to their WM capacity.