Two experiments examined whether over-selectivity is the product of a post-acquisition performance deficit, rather than an attention problem. In both experiments, children with Autistic Spectrum Disorder were presented with a trial-and-error discrimination task using two, two-element stimuli and over-selected in both studies. After behavioral control by the previously over-selected stimulus was extinguished, behavioral control by the previously under-selected cue emerged without direct training. However, this effect was only found in higher-functioning children, and not with more severely impaired children. These findings suggest that over-selectivity is not simply due to a failure to attend to all of the stimuli presented. They also suggest that extinction of over-selected stimuli may be a fruitful line of intervention for clinical intervention for some individuals.

No abstract

Stimulus overselectivity occurs when only one of potentially many aspects of the environment controls behavior. Adult participants were trained and tested on a trial-and-error discrimination learning task while engaging in a concurrent load task, and overselectivity emerged. When responding to the overselected stimulus was reduced by reinforcing a novel stimulus in the presence of the previously overselected stimulus in a second trial-and-error discrimination task, behavioral control by the underselected stimulus became stronger. However, this result was only found under certain circumstances: when there was substantial overselectivity in the first training phase; when control by the underselected stimulus in the first phase was particularly low; and when there was effective reduction in the behavioral control exerted by the previously overselected stimuli. The emergence of behavioral control by the underselected stimulus suggests that overselectivity is not simply due to an attention deficit, because for the emergence to occur, the stimuli must have been attended to and learned about in the training phase; but that a range of additional learning factors may play a role.

No abstract