Spatial attention in the mental architecture: Evidence from neuropsychology

Abstract

Using neuropsychological evidence, this paper examines whether spatial attention functions as a domain-specific module or as a more general-purpose central processor. Data are presented from two spatial attention cuing tasks completed by subjects, with an acquired attentional deficit, and control subjects. In both tasks, an arrow indicated with high probability the side of response (response task) or the side of space on which the stimulus would appear (visuospatial task). In the response task, the stimuli appeared foveally and the response component was lateralized, and in the visuospatial task, the stimuli were lateralized and the response component remained constant in the midline. Only the neglect subjects showed a disproportionate increase in reaction time on both the response and visuospatial tasks when the arrow cued the subject to the ipsilateral side and the stimulus or response was on the side of space contralateral to the lesion. The substantial association across the two tasks suggests that a common underlying internal spatial representation subserves perception and action. While this finding is consistent with Fodor's view of a cross-domain processor, it does not meet all of his criteria of a central processor. We conclude, therefore, that the posterior attentional mechanism is strictly neither a module nor a central processor. Rather, these results suggest that a common attentional mechanism may subserve behavior in domains that are tightly coupled.

Object-centered not scene-based visual neglect.

“…These data may imply that there are multiple frames of reference in which neglect arises, and that the variety of lesion sites or severities will influence these multiple frames in different ways. Similar observations regarding the effect of severity on performance have been made by Behrmann, Black, and Murji (1995) and by Driver and Halligan (1991). This participant variability may be used to great advantage in future research.…”

Time to imagine space: a chronometric exploration of representational neglect

“…This, however, introduced a potential problem in the interpretation of the results. Patients with left neglect may show a response bias when asked to press lateralized keys (even if they are close to each other, as in the present study), with faster responses for right-sided keys than for left-sided keys (Behrmann, Black, & Murji, 1995;Làdavas, Farne, Carletti, & Zeloni, 1994). Thus, slower RTs for left-sided imagined locations might in fact originate from a response bias, and not from an imaginal impairment 1 .…”

Attentional bias to emotional stimuli is altered during moderate- but not high-intensity exercise.

“…Some stimuli are preferentially processed because the brain presumably has been designed to process salient stimuli more so than nonsalient stimuli. Experimental studies have generally confirmed that relevant or salient visual stimuli produce deeper or more effective cognitive processing than other irrelevant stimuli (Behrmann, Black, & Murji, 1995;Danckert et al, 2000;Egeth & Yantis, 1997;Fuster, 1990;Yantis & Jonides, 1984). Emotional stimuli, in particular, have been shown to naturally engage the visual attention system (Keil, Moratti, Sabatinelli, Bradley, & Lang, 2005).…”