Non-spatial extinction following lesions of the parietal lobe in humans

  title={Non-spatial extinction following lesions of the parietal lobe in humans},
  author={Glyn W. Humphreys and Cristina Romani and Andrew C. Olson and Malcolm Riddoch and John Duncan},
EFFICIENT behaviour in the visual environment requires selection between stimuli competing for control of action. Many current models of selection are spatial: relevant objects are chosen by attending to their locations1–3. The unilateral stimulus extinction observed following lesions of the parietal lobe provides evidence for spatial selection4. Such patients may identify a single stimulus presented in their contralesional field, but can fail to detect the same stimulus when a competing… 

Expectation-based attentional modulation of visual extinction in spatial neglect

Visual extinction and cortical connectivity in human vision.

Extinction: a window into attentional competition.

Transient binding by time: Neuropsychological evidence from anti-extinction

A series of experiments that examine the factors that lead to anti-extinction in a patient GK, who has bilateral parietal lesions but more impaired identification of left-side stimuli, interpret the data as indicating that there is unconscious and transient temporal binding in vision.

Contrast dependence of perceptual grouping in brain-damaged patients with visual extinction.

The present demonstration of contrast dependency in such processing, strengthens the previous conjecture that even in the presence of significant, extinction producing, parietal damage, the primary visual cortex preserves the capacity to encode, using long-range lateral interactions, an image description in which visual objects are already segregated from background.



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

Space- and object-based attention components were examined in neurologically normal and parietal-lesion subjects, who detected a luminance change at 1 of 4 ends of 2 outline rectangles, indicating a spatial deficit and object deficit.

On Varying the Span of Visual Attention: Evidence for Two Modes of Spatial Attention

Three experiments investigated whether subjects could selectively attend to a target item presented in close spatial proximity to a distractor element, with the result that there is differential processing of attended items even within the formerly critical area.

Simultanagnosia. To see but not two see.

It is suggested that the patient's simultanagnosia is attributable to an impairment in the process by which activated structural descriptions are linked to information coding the location of the object.

Selective attention gates visual processing in the extrastriate cortex.

The filtering of irrelevant information from the receptive fields of extrastriate neurons may underlie the ability to identify and remember the properties of a particular object out of the many that may be represented on the retina.

Analysis of visual behavior

Analysis of Visual Behavior deals with the visual mechanisms of diverse vertebrate species from salamanders and toads to primates and humans and presents a stimulating interaction of the disciplines of anatomy, physiology, and behavioral science.

On the Interaction of Selective Attention and Lexical Knowledge: A Connectionist Account of Neglect Dyslexia

The convergence of findings from the neuropsychological research and the computational modeling sheds light on the role of attention in normal visuospatial processing, supporting a hybrid view of attentional selection that has properties of both early and late selection.

Coordination of what and where in Visual Attention

Results suggest that ‘what?’ and ‘where?” systems are coordinated in visual attention: their separate outputs can be used simultaneously without cost, but only when they concern one object.

Effects of parietal injury on covert orienting of attention

The results show that damage to the parietal lobe produces a deficit in the disengage operation when the target is contralateral to the lesion, and suggest one mechanism of the effects of parietal lesions reported in clinical neurology.

Orienting of Attention*

  • M. Posner
  • Psychology
    The Quarterly journal of experimental psychology
  • 1980
This paper explores one aspect of cognition through the use of a simple model task in which human subjects are asked to commit attention to a position in visual space other than fixation by orienting a covert mechanism that seems sufficiently time locked to external events that its trajectory can be traced across the visual field in terms of momentary changes in the efficiency of detecting stimuli.