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Visual attention and visual working memory exert severe capacity limitations on cognitive processing. Impairments in both functions may exacerbate the social and communication deficits seen in children with an autism spectrum disorder (ASD). This study characterizes spatial working memory and visual attention in school-age children with high-functioning autism. Children with ASD, and age, gender, and IQ-matched typically developing (TD) children performed 2 tasks: a spatial working memory task and an attentive tracking task. Compared with TD children, children with ASD showed a more pronounced deficit in the spatial working memory task than the attentive tracking task, even though the latter placed significant demands on sustained attention, location updating, and distractor inhibition. Because both groups of children were sensitive to configuration mismatches between the sample and test arrays, the spatial working memory deficit was not because of atypical organization of spatial working memory. These findings show that attention and working memory are dissociable, and that children with ASD show a specific deficit in buffering visual information across temporal discontinuity. [ABSTRACT FROM AUTHOR]

Deficits in explicit spatial memory, as well as abnormalities of the hippocampus and neighboring medial temporal structures, have been documented in schizophrenia and depression. Recent evidence relying on the contextual cueing paradigm has shown that integrity of these structures is crucial not only for explicit memory but also for implicit spatial memory. Using this paradigm, the authors show that implicit memory for spatial context is severely impaired in clinically depressed patients but reaches a normal level in schizophrenia patients, although in these patients, acquisition is slower than in controls. By contrast, implicit memory for isolated locations and colors is normal in both schizophrenia and depressed patients. These findings suggest an implicit memory impairment specific to spatial context in depression. The implications for research on the differences between schizophrenia and depression in abnormalities of the hippocampal system and for research on the neural correlates of contextual cueing are discussed. [ABSTRACT FROM AUTHOR]