Blindsight modulation of motion perception.

Monkey data suggest that of all perceptual abilities, motion perception is the most likely to survive striate damage. The results of studies on motion blindsight in humans, though, are mixed. We used an indirect strategy to examine how responses to visible stimuli were modulated by blind-field stimuli.

Antisaccades and task-switching: interactions in controlled processing.

Smaller latency costs for switching from dominant (habitual) to non-dominant (unusual) tasks compared to the reverse direction have been noted in some studies of task-switching. This asymmetry has been cited as evidence of inhibitory effects from the prior trial. We examined accuracy and latency costs of task-switching between prosaccades and antisaccades, where task-switching is limited to stimulus-response re-mapping and occurs between tasks highly asymmetric in dominance.

Schizophrenic subjects show deficient inhibition but intact task switching on saccadic tasks.

Background: Schizophrenic patients have executive function deficits, presumably on the basis of prefrontal cortex dysfunction. Although they consistently show impaired inhibition, the evidence of a task switching deficit is less consistent and is often based on performance of neuropsychological tests that require several cognitive processes (e.g.

Antisaccades and task switching: studies of control processes in saccadic function in normal subjects and schizophrenic patients.

Executive functions allow us to respond flexibly rather than stereotypically to the environment. We examined two such functions, task switching and inhibition in the antisaccade paradigm, in two studies. One study involved 18 normal subjects; the other, 21 schizophrenic patients and 16 age-matched controls.

Discrimination of spatial relations and features in faces: Effects of inversion and viewing duration.

We studied discrimination of changes in eye position, mouth position, and eye colour at viewing durations ranging from 1 second to unlimited time. With upright faces, perception was rapid and did not improve above 2 seconds viewing time. Face inversion impaired discrimination of mouth position significantly, eye position slightly, but not eye colour.

Lesions of the fusiform face area impair perception of facial configuration in prosopagnosia.

Background: Prosopagnosia, the inability to recognize faces, is associated with medial occipitotemporal lesions, especially on the right. Functional imaging has revealed a focal region in the right fusiform gyrus activated specifically during face perception.

Objective: The study attempted to determine whether lesions of this region were associated with defects in face perception in patients with prosopagnosia.