Effects of flunitrazepam on responses to lateralized visual stimuli: evidence for cerebral asymmetry of execution of manual movements to targets in contralateral and ipsilateral visual space

AbstractIt is well established that neural responses to visual stimuli are enhanced at select locations in the visual field. While spatial selectivity and the effects of spatial attention are well-understood for discrete tasks (e.g., visual cueing paradigms), little is known about neural response during a naturalistic visual experience that involves complex dynamic visual stimuli, for instance, driving. In this study, we assess the strength of neural responses across the visual space during a kart race video game. Specifically, we measure the correlation strength of scalp evoked potentials with optical flow magnitude at individual locations on the screen. We find the strongest neural responses for task-relevant locations in visual space, selectively extending to areas beyond the focus of overt attention: while the driver’s gaze is directed upon the heading direction at the center of the screen, we observe robust neural evoked responses also to peripheral areas such as the road and surrounding buildings. Importantly, this spatial selectivity of neural responses differs across scalp locations. Moreover, during active gameplay, the strength of the spatially-selective neural responses are enhanced compared to passive viewing. Spatially selective neural gains have previously been interpreted as an attentional gain mechanism. In this view, the present data suggest that different brain areas focus attention on different task-relevant portions of the visual field, reaching beyond the focus of overt attention.

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The Influence of Visual Cues on the Localisation of Circular Auditory Motion

Perception ◽

10.1068/p240457 ◽

1995 ◽

Vol 24 (4) ◽

pp. 457-465 ◽

Cited By ~ 7

Author(s):

Stephen Lakatos

Keyword(s):

Visual Cues ◽

Visual Stimuli ◽

Frontal Plane ◽

Visual Space ◽

Auditory Motion ◽

Auditory Cues ◽

Light Emitting ◽

Rapid Sequence ◽

Sequential Activation ◽

Relative Inability

A relative inability of listeners to refer auditory motion properly to the front hemifield when a rapid circular trajectory is traced around them in the horizontal plane was investigated. It was hypothesised that the representations of visual space and auditory frontal space are linked in such a way that auditory cues alone are insufficient to determine the veridical path in the front hemifield when both the front and the rear hemifield receive circular auditory input in rapid sequence. Listeners discriminated the direction of a rapid apparent trajectory created by the sequential activation of various combinations of loudspeakers and light-emitting diodes spaced evenly in a circular array. The addition of visual stimuli to the front hemifield, even when lacking motional cues, improved discrimination significantly. Conversely, when the same portion of the trajectory presented to the front hemifield consisted only of visual stimuli, performance decreased markedly. Additional conditions, in which the trajectory was restricted to a 120 deg path in the frontal plane, confirmed these effects. The findings suggest that the presence of a visual cue enhances the perception of auditory directionality, even when it does not itself provide any motion information.

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Selective gating of retinal information by arousal

10.1101/2020.03.12.989913 ◽

2020 ◽

Author(s):

Liang Liang ◽

Alex Fratzl ◽

Omar El Mansour ◽

Jasmine D.S. Reggiani ◽

Chinfei Chen ◽

...

Keyword(s):

Visual Processing ◽

Visual Information ◽

Visual Stimuli ◽

Sensory Information ◽

Visual Space ◽

Wide Field ◽

Visual Responses ◽

Visual Thalamus ◽

Spatial Frequencies ◽

Retinal Information

SummaryHow sensory information is processed by the brain can depend on behavioral state. In the visual thalamus and cortex, arousal/locomotion is associated with changes in the magnitude of responses to visual stimuli. Here, we asked whether such modulation of visual responses might already occur at an earlier stage in this visual pathway. We measured neural activity of retinal axons using wide-field and two-photon calcium imaging in awake mouse thalamus across arousal states associated with different pupil sizes. Surprisingly, visual responses to drifting gratings in retinal axonal boutons were robustly modulated by arousal level, in a manner that varied across stimulus dimensions and across functionally distinct subsets of boutons. At low and intermediate spatial frequencies, the majority of boutons were suppressed by arousal. In contrast, at high spatial frequencies, the proportions of boutons showing enhancement or suppression were more similar, particularly for boutons tuned to regions of visual space ahead of the mouse. Arousal-related modulation also varied with a bouton’s sensitivity to luminance changes and direction of motion, with greater response suppression in boutons tuned to luminance decrements vs. increments, and in boutons preferring motion along directions or axes of optic flow. Together, our results suggest that differential filtering of distinct visual information channels by arousal state occurs at very early stages of visual processing, before the information is transmitted to neurons in visual thalamus. Such early filtering may provide an efficient means of optimizing central visual processing and perception of state-relevant visual stimuli.

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Word Association of Time-Altered Auditory and Visual Stimuli in Aphasia

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.2403.469b ◽

1981 ◽

Vol 24 (3) ◽

pp. 469-469

Author(s):

Robert Goldfarb ◽

Harvey Halpern

Keyword(s):

Word Association ◽

Visual Stimuli

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Response and Reinforcement in Operant Audiometry

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.5203.294 ◽

1987 ◽

Vol 52 (3) ◽

pp. 294-299 ◽

Cited By ~ 8

Author(s):

Michael A. Primus

Keyword(s):

Operant Conditioning ◽

Space Versus ◽

Visual Space ◽

Central Processing ◽

Operant Discrimination ◽

Conditioning Rate ◽

Significant Difference ◽

Simple Detection ◽

Variable Success ◽

Response Task

Variable success in audiometric assessment of young children with operant conditioning indicates the need for systematic examination of commonly employed techniques. The current study investigated response and reinforcement features of two operant discrimination paradigms with normal I7-month-old children. Findings indicated more responses prior to the onset of habituation when the response task was based on complex central processing skills (localization and coordination of auditory/visual space) versus simple detection. Use of animation in toy reinforcers resulted in more than a twofold increase in the number of subject responses. Results showed no significant difference in response conditioning rate or consistency for the response tasks and forms of reinforcement examined.

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