Cortex Controls Multisensory Depression in Superior Colliculus

2003 ◽  
Vol 90 (4) ◽  
pp. 2123-2135 ◽  
Author(s):  
Wan Jiang ◽  
Barry E. Stein
Keyword(s):  
Receptive Field ◽  
Superior Colliculus ◽  
Multisensory Integration ◽  
Auditory Stimulus ◽  
Visual Stimulus ◽  
Sensory Stimulus ◽  
Visual Orientation ◽  
Orientation Behavior ◽  
Cortical Areas

Multisensory depression is a fundamental index of multisensory integration in superior colliculus (SC) neurons. It is initiated when one sensory stimulus (auditory) located outside its modality-specific receptive field degrades or eliminates the neuron's responses to another sensory stimulus (visual) presented within its modality-specific receptive field. The present experiments demonstrate that the capacity of SC neurons to engage in multisensory depression is strongly dependent on influences from two cortical areas (the anterior ectosylvian and rostral lateral suprasylvian sulci). When these cortices are deactivated, the ability of SC neurons to synthesize visual-auditory inputs in this way is compromised; multisensory responses are disinhibited, becoming more vigorous and in some cases indistinguishable from responses to the visual stimulus alone. Although obtaining a more robust multisensory SC response when cortex is nonfunctional than when it is functional may seem paradoxical, these data may help explain previous observations that the loss of these cortical influences permits visual orientation behavior in the presence of a normally disruptive auditory stimulus.

Behavioral Indices of Multisensory Integration: Orientation to Visual Cues is Affected by Auditory Stimuli

1989 ◽  
Vol 1 (1) ◽  
pp. 12-24 ◽  
Author(s):  
Barry E. Stein ◽  
M. Alex Meredith ◽  
W. Scott Huneycutt ◽  
Lawrence McDade
Keyword(s):  
Superior Colliculus ◽  
Single Cell ◽  
Multisensory Integration ◽  
Auditory Stimulus ◽  
Visual Cues ◽  
Single Cells ◽  
Receptive Fields ◽  
Visual Cue ◽  
Overt Behavior ◽  
Low Intensity

Physiological studies have demonstrated that inputs from different sensory modalities converge on, and are integrated by, individual superior colliculus neurons and that this integration is governed by specific spatial rules. The present experiments were an attempt to relate these neural processes to overt behavior by determining if behaviors believed to involve the circuitry of the superior colliculus would show similar multisensory dependencies and be subject to the same rules of integration. The neurophysiological-behavioral parallels proved to be striking. The effectiveness of a stimulus of one modality in eliciting attentive and orientation behaviors was dramatically affected by the presence of a stimulus from another modality in each of the three behavioral paradigms used here. Animals trained to approach a low intensity visual cue had their performance significantly enhanced when a brief, low intensity auditory stimulus was presented at the same location as the visual cue, but their performance was significantly depressed when the auditory stimulus was disparate to it. These effects were independent of the animals' experience with the modifying (i.e. auditory) stimulus and exceeded what might have been predicted statistically based on the animals' performance with each single-modality cue. The multiplicative nature of these multisensory interactions and their dependence on the relative positions and intensities of the two stimuli were all very similar to those observed physiologically for single cells. The few differences that were observed appeared to reflect the fact that understanding integration at the level of the single cell requires reference to the individual cell's multisensory receptive field properties, while at the behavioral level populations of receptive fields must be evaluated. These data illustrate that the rules governing multisensory integration at the level of the single cell also predict responses to these stimuli in the intact behaving organism.

Enhancement of visual responses in monkey striate cortex and frontal eye fields

1976 ◽  
Vol 39 (4) ◽  
pp. 766-772 ◽  
Author(s):  
R. H. Wurtz ◽  
C. W. Mohler
Keyword(s):  
Receptive Field ◽  
Superior Colliculus ◽  
Visual Stimulus ◽  
Striate Cortex ◽  
Frontal Eye Field ◽  
Enhancement Effect ◽  
Frontal Eye Fields ◽  
Visual Response ◽  
Visual Responses ◽  
Response Enhancement

1. We have studied the visual enhancement effect in two areas of the cerebral cortex of monkeys. The response of the cells to a visual stimulus was determined both when the monkey used the visual stimulus as the target for a saccadic eye movement and when he did not. 2. In striate cortex cells with nonoriented, simple, complex, and hypercomplex receptive-field types were studied. Clear enhancement of the response to the appropriate visual stimulus was seldom seen when the monkey used the stimulus as a target for a saccade. In addition, any enhancement effect seen was nonselective; it occurred whether the monkey made a saccade to the receptive-field stimulus or some other stimulus at a point distant from the receptive field. The enhancement also occurred whether the monkey made a saccade to the stimulus or just released the bar when the stimulus dimmed. 3. This nonselective enhancement in striate cortex is in striking contrast to the selective enhancement of the visual response seen in the superior colliculus. The different characteristics of the enhancement in striate cortex and the observation of enhancement in the colliculus following ablation of striate cortex suggest that this cortical area is an unlikely source of the collicular enhancement. 4. These observations reinforce the distinction between striate cortex and superior colliculus. Striate cortex is an excellent analyzer of stimulus characteristics but a poor evaluator of stimulus significance. The superior colliculus is an excellent evaluator but a poor analyzer. 5. The area of frontal eye fields in which cells have clear visual responses has been better localized. Enhancement of the visual response of these cells also occurs and, at least for some cells, the response enhancement is selective. The response enhancement, like the visual properties of these frontal eye field cells, appears to be more closely related to the properties of superior colliculus cells than to striate cortex cells.

Reliability of an Attention-Assessing Technique

1984 ◽  
Vol 59 (1) ◽  
pp. 212-214
Author(s):  
H. W. Craver
Keyword(s):  
Auditory Stimulus ◽  
Visual Stimulus ◽  
Experimental Situation ◽  
Auditory Stimuli ◽  
Self Monitoring ◽  
Monitoring Techniques ◽  
Self Reports

The reliability of an attention-focusing technique was assessed for 12 subjects over 4 sessions. Subjects' thought intrusions were counted while they were focusing on either visual or auditory stimuli. Digital temperatures were recorded and an experimental-situation questionnaire was administered. This technique provides extremely reliable self-reports across the sessions. The total number of intrusions was higher for the auditory stimulus than for the visual stimulus. The study's relevance to assessing self-monitoring techniques such as meditation is discussed.

The Effects of Cue Reliability on Crossmodal Recalibration in Adults and Children

2021 ◽  
pp. 1-19
Author(s):  
Sophie Rohlf ◽  
Patrick Bruns ◽  
Brigitte Röder
Keyword(s):  
Multisensory Integration ◽  
Sound Localization ◽  
Visual Stimulus ◽  
Cue Combination ◽  
Single Exposure ◽  
Visual Cue ◽  
Cue Reliability ◽  
Adults And Children ◽  
Ventriloquist Effect

Abstract Reliability-based cue combination is a hallmark of multisensory integration, while the role of cue reliability for crossmodal recalibration is less understood. The present study investigated whether visual cue reliability affects audiovisual recalibration in adults and children. Participants had to localize sounds, which were presented either alone or in combination with a spatially discrepant high- or low-reliability visual stimulus. In a previous study we had shown that the ventriloquist effect (indicating multisensory integration) was overall larger in the children groups and that the shift in sound localization toward the spatially discrepant visual stimulus decreased with visual cue reliability in all groups. The present study replicated the onset of the immediate ventriloquist aftereffect (a shift in unimodal sound localization following a single exposure of a spatially discrepant audiovisual stimulus) at the age of 6–7 years. In adults the immediate ventriloquist aftereffect depended on visual cue reliability, whereas the cumulative ventriloquist aftereffect (reflecting the audiovisual spatial discrepancies over the complete experiment) did not. In 6–7-year-olds the immediate ventriloquist aftereffect was independent of visual cue reliability. The present results are compatible with the idea of immediate and cumulative crossmodal recalibrations being dissociable processes and that the immediate ventriloquist aftereffect is more closely related to genuine multisensory integration.

scholarly journals Multisensory Integration in the Superior Colliculus of the Alert Cat

1998 ◽  
Vol 80 (2) ◽  
pp. 1006-1010 ◽  
Author(s):  
Mark T. Wallace ◽  
M. Alex Meredith ◽  
Barry E. Stein
Keyword(s):  
Superior Colliculus ◽  
Multisensory Integration ◽  
Sensory Response ◽  
Functional Link ◽  
Sensory Stimuli ◽  
Response Properties ◽  
Alert Cat

Wallace, Mark T., M. Alex Meredith, and Barry E. Stein. Multisensory integration in the superior colliculus of the alert cat. J. Neurophysiol. 80: 1006–1010, 1998. The modality convergence patterns, sensory response properties, and principles governing multisensory integration in the superior colliculus (SC) of the alert cat were found to have fundamental similarities to those in anesthetized animals. Of particular interest was the observation that, in a manner indistinguishable from the anesthetized animal, combinations of two different sensory stimuli significantly enhanced the responses of SC neurons above those evoked by either unimodal stimulus. These observations are consistent with the speculation that there is a functional link among multisensory integration in individual SC neurons and cross-modality attentive and orientation behaviors.

Context dependence of receptive field remapping in superior colliculus

2011 ◽  
Vol 106 (4) ◽  
pp. 1862-1874 ◽  
Author(s):  
Jan Churan ◽  
Daniel Guitton ◽  
Christopher C. Pack
Keyword(s):  
Receptive Field ◽  
Superior Colliculus ◽  
Visual Stimulation ◽  
Receptive Fields ◽  
Spatial Location ◽  
Macaque Monkey ◽  
Visual Signals ◽  
Perceptual Stability ◽  
Visual Background ◽  
The Brain

Our perception of the positions of objects in our surroundings is surprisingly unaffected by movements of the eyes, head, and body. This suggests that the brain has a mechanism for maintaining perceptual stability, based either on the spatial relationships among visible objects or internal copies of its own motor commands. Strong evidence for the latter mechanism comes from the remapping of visual receptive fields that occurs around the time of a saccade. Remapping occurs when a single neuron responds to visual stimuli placed presaccadically in the spatial location that will be occupied by its receptive field after the completion of a saccade. Although evidence for remapping has been found in many brain areas, relatively little is known about how it interacts with sensory context. This interaction is important for understanding perceptual stability more generally, as the brain may rely on extraretinal signals or visual signals to different degrees in different contexts. Here, we have studied the interaction between visual stimulation and remapping by recording from single neurons in the superior colliculus of the macaque monkey, using several different visual stimulus conditions. We find that remapping responses are highly sensitive to low-level visual signals, with the overall luminance of the visual background exerting a particularly powerful influence. Specifically, although remapping was fairly common in complete darkness, such responses were usually decreased or abolished in the presence of modest background illumination. Thus the brain might make use of a strategy that emphasizes visual landmarks over extraretinal signals whenever the former are available.

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