Isolating attentional systems: A cognitive-anatomical analysis

Abstract

Downing & Pinker, 1985;Posner, 1980).Each of these operations appears to be affected by a different form of brain injury. Damage to the parietal lobe can produce a severe deficit in the ability to disengage attention from a visual location, without any loss in efficiency of the move or engage operations (posner, Walker, Friedrich, & Rafal, 1984). Our results show only small

Shifting visual attention between objects and locations: Evidence from normal and parietal lesion subjects.

“…There were no significant differences between horizontal and vertical shifts of attention from invalid cues to targets in these analyses. The spatial disengage difficulty with horizontal shifts to an invalidly cued contralesional target replicates the previous findings of Posner, Inhoff, et al (1987), and the difficulty with vertical shifts within the contralesional field replicates the observations of Baynes et al (1986). Of course, a lack of power may be masking a real difference between vertical and horizontal shifts.…”

“…Impaired attentional disengagement from objects was operationally measured by exaggerated costs from invalid cuing of the rectangle where the target did not appear. This follows the logic Posner et al established (1984;Posner, Inhoff, et al, 1987;Posner, Walker, et al, 1987), although in our critical conditions the invalid cue specified an inappropriate object as well as an inappropriate location. On Posner et al's assumption that exaggerated costs from invalid cues reveal the defective operation of disengage systems, our results suggest that the left hemisphere is specialized for disengaging attention from objects.…”

“…Our measure of the spatial component revealed the abnormality that has previously been associated with unilateral parietal injury by other investigators. That is, the parietal patients showed a greater cost of invalid cuing for contralesional targets than for ipsilesional targets-the spatial disengage deficit previously reported by Baynes et al (1986), Morrow andRatcliff (1988), andPetersen et al (1989) and originally observed by Posner et al (1984;Posner, Inhoff, et al, 1987;Posner, Walker, et al, 1987).…”

Socialization and attentional deficits under focusing and divided attention conditions.

“…In this context, when one of two concurrent tasks is given processing priority, low-So individuals may be less able than high-So individuals to disengage attention from a primary task channel (or primary task events), less able to reallocate attention in response to secondary task events, or less able to accomplish either of these things. Testing hypotheses for underlying mechanisms appears to require further research and different paradigms than those employed here (e.g., see Jonides, 1981;Posner, Inhoff, Friedrich, & Cohen, 1985).…”

Feature integration and spatial attention: More evidence of a dissociation between endogenous and exogenous orienting.

“…This latter assumption may be risky because endogenous visual cues most likely involve the operation of a second, anterior attention system. This attention system is not devoted only to spatial processing but it also seems to be a general-purpose system that can be applied to several tasks (Carr, 1992; Nakagawa, 1991; Posner, Inhoff, Freidrich, & Cohen, 1987; Posner & Peterson, 1990; Posner, Sandson, Dhawan, & Shulman, 1989). With respect to studies of visual attention, the use of endogenous cues has been an accepted practice because it is assumed (at least implicitly) that, although the anterior system might be needed to interpret the cues, it merely exerts voluntary control over the operation of the posterior spatial attention system.…”