Enhancement of perceptual sensitivity as the result of selectively attending to spatial locations

Abstract

The present experiment employed a visual signal-detection task within a cost-benefit (inhibitionfacilitation) paradigm to examine the effects of selective attention on perceptual sensitivity. A central cue directed the subjects' attention to either a right or a left spatial location where a detection task was performed. The cue was either a high/low or neutral-validity indicator of the position in which an event was likely to occur. A rating-scale response scheme in conjunction with the subjects' target signallocational judgments allowed for the construction of ROC curves for each condition. Significant benefits were found for all subjects, supporting the hypothesis that selective attention can enhance perceptual sensitivity. Deallocation of attention resulted in an inhibition of sensitivity in unattended spatial locations. Subjects were consistently most sensitive in the right spatial location. There were no significant differences in overall response bias among the three conditions or in spatial locations. The results support theories of attention, such as "perceptual tuning," that suggest very early selective control.

Dissociable prior influences of signal probability and relevance on visual contrast sensitivity

“…Characterizing the mechanisms by which attention enhances sensory processing at the behavioral and neuronal levels is a key goal of the neurosciences, and a large body of literature has used signal detection theory to measure increases in contrast sensitivity when a relevant stimulus is presented at an expected location relative to an unexpected one (3)(4)(5)(6)(7)(8)(9)(10). Most, if not all, of these studies have manipulated top-down attention using spatial cues that predict the occurrence of a target stimulus at a particular location (22).…”

“…SDT posits that performance can be summarized by two statistics: d′, indexing sensitivity to signal occurrence in signal-to-noise units, and c, reflecting a bias to report signal occurrence (modeled as a decision criterion). Using this approach, it is now well established that cues that predict the location of a behaviorally relevant signal increase sensitivity (3)(4)(5)(6) by improving the precision of visual processing (7)(8)(9)(10). By contrast, cues that predict a greater probability of signal occurrence alone are believed to have no influence on sensitivity (11,12) but instead bias observers to report signal occurrence by adopting a more liberal decision criterion.…”

When does visual attention select all features of a distractor?

“…There is extensive evidence that attention increases the speed and/or accuracy of processing stimuli at the attended location relative to elsewhere (Posner, Snyder, & Davidson, 1980;Shaw & Shaw, 1977). It reduces response variability (Prinzmetal, Amiri, Allen, & Edwards, 1998;Prinzmetal & Wilson, 1997) and enhances signal-to-noise ratio of a briefly displayed stimulus (Bashinski & Bacharach, 1980;Downing, 1988). Attending to a stimulus on one part of an object also facilitates the processing of other stimuli that pertain to the same object (Chen, 1998;Chen & Cave, in press;Duncan, 1984;Egly, Driver, & Rafal, 1994;see Scholl, 2001, for a review).…”

Visual attention and stability

“…without making an eye movement) to a stimulus, we perceive that stimulus more clearly than we would if attention were unfocused or directed elsewhere. This increased perceptual ability can be measured as an increased sensitivity to faint stimuli [3], enhancement of perceived contrast [4] and decreased reaction times to attended stimuli [5]. In addition, visual attention is characterized by an inhibitory surround: processing of stimuli outside of but near the focus of attention is suppressed (e.g.…”