The superior colliculus is sensitive to gestalt-like stimulus configuration in hemispherectomy patients

Alterations to multisensory and unisensory integration by stimulus competition

Journal of Neurophysiology ◽

10.1152/jn.00509.2011 ◽

2011 ◽

Vol 106 (6) ◽

pp. 3091-3101 ◽

Cited By ~ 15

Author(s):

Scott R. Pluta ◽

Benjamin A. Rowland ◽

Terrence R. Stanford ◽

Barry E. Stein

Keyword(s):

Superior Colliculus ◽

Multisensory Integration ◽

Individual Component ◽

Selection Process ◽

Stimulus Configuration ◽

Competitive Interactions ◽

Stimulus Selection ◽

Multiple Targets ◽

Interhemispheric Competition ◽

Stimulus Environment

In environments containing sensory events at competing locations, selecting a target for orienting requires prioritization of stimulus values. Although the superior colliculus (SC) is causally linked to the stimulus selection process, the manner in which SC multisensory integration operates in a competitive stimulus environment is unknown. Here we examined how the activity of visual-auditory SC neurons is affected by placement of a competing target in the opposite hemifield, a stimulus configuration that would, in principle, promote interhemispheric competition for access to downstream motor circuitry. Competitive interactions between the targets were evident in how they altered unisensory and multisensory responses of individual neurons. Responses elicited by a cross-modal stimulus (multisensory responses) proved to be substantially more resistant to competitor-induced depression than were unisensory responses (evoked by the component modality-specific stimuli). Similarly, when a cross-modal stimulus served as the competitor, it exerted considerably more depression than did its individual component stimuli, in some cases producing more depression than predicted by their linear sum. These findings suggest that multisensory integration can help resolve competition among multiple targets by enhancing orientation to the location of cross-modal events while simultaneously suppressing orientation to events at alternate locations.

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Decision letter for "Monosynaptic Inputs To Specific Cell Types Of The Intermediate And Deep Layers Of The Superior Colliculus"

10.1002/cne.24888/v1/decision1 ◽

2019 ◽

Keyword(s):

Superior Colliculus ◽

Cell Types ◽

Specific Cell ◽

Deep Layers

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Ultrastructure of developing visual cortical synapses in the cat superior colliculus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100085083 ◽

1991 ◽

Vol 49 ◽

pp. 156-157

Author(s):

Caroline A. Miller ◽

Laura L. Bruce

Keyword(s):

Superior Colliculus ◽

Phosphate Buffer ◽

Receptive Fields ◽

Visual Cortical Area ◽

Cortical Synapses ◽

Visual Cortical ◽

And Function ◽

Phosphate Buffered Saline ◽

The Brain ◽

Cat Superior Colliculus

The first visual cortical axons arrive in the cat superior colliculus by the time of birth. Adultlike receptive fields develop slowly over several weeks following birth. The developing cortical axons go through a sequence of changes before acquiring their adultlike morphology and function. To determine how these axons interact with neurons in the colliculus, cortico-collicular axons were labeled with biocytin (an anterograde neuronal tracer) and studied with electron microscopy.Deeply anesthetized animals received 200-500 nl injections of biocytin (Sigma; 5% in phosphate buffer) in the lateral suprasylvian visual cortical area. After a 24 hr survival time, the animals were deeply anesthetized and perfused with 0.9% phosphate buffered saline followed by fixation with a solution of 1.25% glutaraldehyde and 1.0% paraformaldehyde in 0.1M phosphate buffer. The brain was sectioned transversely on a vibratome at 50 μm. The tissue was processed immediately to visualize the biocytin.

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