Information processing and aspects of visual attention in children with the DSM-III-R diagnosis “pervasive developmental disorder not otherwise specified” (PDDNOS): II. sustained attention

Abstract
A group of 15 nonhyperactive children of normal intelligence with the DSM-III-R diagnosis “pervasive developmental disorder not otherwise specified” (PDDNOS) performed a sustained attention task. Adopting a cognitive-energetical linear stage model of human information processing, we investigated whether task performances deteriorated due to a diminishing level of arousal, activation, or by the active ‘effortful’ mode of information processing. In comparison to an age-matched group of normal children, the patients showed no sharper decrease in perceptual sensitivity (d'). D' is assumed to be a measure of arousal. However, the children with PDDNOS exhibited large fluctuations in their response bias beta (β), which is assumed to be a measure of activation. During the first part of the task, they shifted between under- and overestimating negative responses. In the latter part of the task this pattern altered to significantly overestimating the number of negative responses. This indicates that the patients were not able to appropriately tune to the task-inherent response probability. Moreover, as compared to the control children, the patients showed a significantly sharper decrease in hit rate with time on task, despite the fact that feedback was given on the errors. The findings are interpreted as an increasing loss of the ability to control the response bias due to difficulties in maintaining the voluntary effortful mode of processing information with prolonged time on task.