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Our current understanding of spatial behaviour and parietal lobe function is largely based on the belief that spatial neglect in humans (a lack of awareness of space on the side of the body contralateral to a brain injury) is typically associated with lesions of the posterior parietal lobe. However, in monkeys, this disorder is observed after lesions of the(More)
Three patients with a right hemisphere lesion and marked left-sided neglect without visual field defects were asked to detect and identify stimuli which were tachistoscopically presented in the left or right visual half-field. Neglect of stimuli presented in the contralesional left visual field, which was observed when the patient's body was in a normal(More)
Spatial neglect is usually assessed using cancellation tests or line bisection. A recent comparison of these tests has revealed a double dissociation, in which one neglect patient was impaired in line bisection but not in star cancellation whereas another showed the reverse deficit. This dissociation has prompted the question whether 'neglect' is still a(More)
The internal representation of space involves the integration of different sensory inputs-visual, somatosensory/proprioceptive, vestibular-yielding reference frames which are not based on individual peripheral sensory codes, being organized instead in ego-centred (e.g. head, trunk, arm) and object- or environment-centred coordinates. Lateralized or(More)
Two patients with left-sided visual extinction after right parietal damage were each given two 'prior entry' tasks that have recently been used to study attentional biases in normals. The first task presented two unconnected bars, one in each visual field, with the patients asked to judge which appeared sooner. Both patients reported that the right bar(More)
This surprising finding prompted the question: what are the functions of the intact right superior temporal cortex in monkey and human? Different experimental observations have led to divergent interpretations. Here I examine the neurophysiological and neuropsychologi-cal contributions to our understanding of the functions of the superior temporal cortex. I(More)
In patients with spatial neglect, contralesional reflexive saccades toward suddenly appearing targets show direction-specific deficits. We examined whether these deficits also occur during free exploration of space. Neglect patients' voluntary eye movements showed reduced amplitudes for saccades in all directions but no direction-specific deficit. The(More)
Some debate remains as to whether underestimation of the horizontal size of objects in the left part of visual space is a general disturbance in spatial neglect. The issue is unclear because size perception may be influenced by factors other than neglect, e.g. visual field defects such as hemianopia. To disentangle these effects, we compared the performance(More)
Do patients with unilateral neglect exhibit direction-specific deficits in the control of movement velocity when performing goal-directed arm movements? Five patients with left-sided neglect performed unrestrained three-dimensional pointing movements to visual targets presented at body midline, the left and right hemispace. A group of healthy adults and a(More)
Various studies have documented that right hemispheric lesions restricted to the basal ganglia or to the thalamus may evoke spatial neglect. However, for methodological reasons, the exact anatomical correlate of spatial neglect within these two subcortical structures still remained uncertain. The present study identified these locations by comparing the(More)