Normal and Impaired Reflexive Orienting of Attention after Central Nonpredictive Cues

Abstract

Abstract& Recent studies suggest that stimuli with directional meaning can trigger lateral shifts of visuospatial attention when centrally presented as noninformative cues. We investigated covert orienting in healthy participants and in a group of 17 right braindamaged patients (9 with hemispatial neglect) comparing arrows, eye gaze, and digits as central nonpredictive cues in a detection task. Orienting effects elicited by arrows and eye gaze were overall consistent in healthy participants and in right braindamaged patients, whereas digit cues were ineffective. Moreover, patients with neglect showed, at the shortest delay between cue and target, a disengage deficit for arrow cueing whose magnitude was predicted by neglect severity. We conclude that the peculiar form of attentional orienting triggered by the directional meaning of arrow cues presents some features previously thought to characterize only the stimulus-driven (exogenous) orienting to noninformative peripheral cues. &

Cue-target contingencies modulate voluntary orienting of spatial attention: dissociable effects for speed and accuracy

“…This type of orienting shares some characteristics with the "genuine" exogenous orienting of attention that is triggered by using peripheral and non predictive cues. Consistent with this assumption, in patients with unilateral spatial neglect, it is plausible that involuntary components mostly contribute to the characteristic disengage deficit for contralesional targets (Bonato, Priftis, Marenzi & Zorzi, 2009;Olk, Hildebrandt, & Kingstone, 2010). However, as already outlined here above, past studies primarily questioned the use of asymmetric symbolic, directional cues as arrows to induce endogenous spatial orienting (Lambert, Roser, Wells, & Heffer, 2006) without studying the role of cue predictivity.…”

The Premotor theory of attention: Time to move on?

“…One possibility is that spatial, directional cues actually primarily activate exogenous attention, rather than endogenous attentional mechanisms. Consistent with this interpretation, a number of studies have shown that arrow cues elicit the very rapid, mandatory shifts of attention (Bonato, Priftis, Marenzi, & Zorzi, 2009;Eimer, 1997;Hommel, Pratt, Colzato, & Godijn, 2001;Tipples, 2002Tipples, , 2008 which are characteristic of exogenous attention. Furthermore, while the cues used by Craighero et al, (2004) were presented foveally, they were not presented centrally.…”

Computer-Based Attention-Demanding Testing Unveils Severe Neglect in Apparently Intact Patients

“…Nevertheless, computer-based testing is seldom, if ever, implemented for the diagnosis of neglect. Thus, many studies on neglect involving a control group of righthemisphere damaged patients, in which the presence of neglect was excluded by means of paper-and-pencil testing (e.g., [9]), may have encompassed some patients with sub-clinical neglect. Only the use of tests on which no compensation is possible allows clinicians to sensitively determine the true degree of impairment and disability of the patients [10].…”