UC Davis

Traditionally, working memory has been defined to include both maintenance mechanisms for storing information and general control mechanisms related to manipulating information. However, modern neuroscientific methods have steered the research into focusing on tasks that explicitly require active maintenance when studying working memory. This dissertation contains two separate experiments showing that working memory is recruited even by very simple tasks, highlighting that working memory does more than simply storing information. Moreover, we show that active maintenance of information is in fact disrupted by interposed simple tasks, but not by task irrelevant automatic processing of stimuli, even when the automatic processing is moderately complex. Furthermore, we provide some evidence suggesting that this disruption of active maintenance can happen even when the interposed task is of a different modality than the maintained items, suggesting that the disruption is caused by modality-independent control mechanisms, and not simply due to the recruitment of the modality-specific storage mechanisms. Lastly, a third experiment provides strong evidence that shifting attention to near-midline stimuli can produce a measurable lateralized evoked activity. This broadens the range of paradigms that can be used to study the effects of lateralized spatial attention and working memory.