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Neural substrates of reliability-weighted visual-tactile multisensory integration.

Beauchamp MS, Pasalar S, Ro T - Front Syst Neurosci (2010)

Bottom Line: When subjects detected viewed and felt touches to the hand, a network of brain areas was active, including visual areas in lateral occipital cortex, somatosensory areas in inferior parietal lobe, and multisensory areas in the intraparietal sulcus (IPS).In agreement with the weighted connection model, the connection weight measured with structural equation modeling between somatosensory cortex and IPS increased for somatosensory-reliable stimuli, and the connection weight between visual cortex and IPS increased for visual-reliable stimuli.This double dissociation of connection strengths was similar to the pattern of behavioral responses during incongruent multisensory stimulation, suggesting that weighted connections may be a neural mechanism for behavioral reliability weighting.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurobiology and Anatomy, University of Texas Health Science Center at Houston Houston, TX, USA.

ABSTRACT
As sensory systems deteriorate in aging or disease, the brain must relearn the appropriate weights to assign each modality during multisensory integration. Using blood-oxygen level dependent functional magnetic resonance imaging of human subjects, we tested a model for the neural mechanisms of sensory weighting, termed "weighted connections." This model holds that the connection weights between early and late areas vary depending on the reliability of the modality, independent of the level of early sensory cortex activity. When subjects detected viewed and felt touches to the hand, a network of brain areas was active, including visual areas in lateral occipital cortex, somatosensory areas in inferior parietal lobe, and multisensory areas in the intraparietal sulcus (IPS). In agreement with the weighted connection model, the connection weight measured with structural equation modeling between somatosensory cortex and IPS increased for somatosensory-reliable stimuli, and the connection weight between visual cortex and IPS increased for visual-reliable stimuli. This double dissociation of connection strengths was similar to the pattern of behavioral responses during incongruent multisensory stimulation, suggesting that weighted connections may be a neural mechanism for behavioral reliability weighting.

No MeSH data available.


Related in: MedlinePlus

The visual stimulus. The visual stimulus consisted of a video of an animated probe (triangular shape) approaching the image of a hand. Three frames of the video are shown. (A) Reliable visual stimulus. Dynamic random noise was overlaid on the visual stimulus. During reliable visual stimulation, the dynamic noise was transparent. (B) Unreliable visual stimulus. During unreliable visual stimulation, the dynamic noise was opaque.
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Figure 1: The visual stimulus. The visual stimulus consisted of a video of an animated probe (triangular shape) approaching the image of a hand. Three frames of the video are shown. (A) Reliable visual stimulus. Dynamic random noise was overlaid on the visual stimulus. During reliable visual stimulation, the dynamic noise was transparent. (B) Unreliable visual stimulus. During unreliable visual stimulation, the dynamic noise was opaque.

Mentions: Subjects performed a two-alternative forced choice task, deciding whether a touch was delivered to the index finger of the right hand or not. Visual stimuli consisted of a 1.5 s video of an animated triangular probe approaching the tip of the index finger of a photograph of an actor's hand (Figure 1). On “visual touch” trials, the probe contacted the finger at t = 1.0 s and then withdrew. On “visual no-touch” trials, the probe stopped just short of the fingertip at t = 1.0 s and then withdrew.


Neural substrates of reliability-weighted visual-tactile multisensory integration.

Beauchamp MS, Pasalar S, Ro T - Front Syst Neurosci (2010)

The visual stimulus. The visual stimulus consisted of a video of an animated probe (triangular shape) approaching the image of a hand. Three frames of the video are shown. (A) Reliable visual stimulus. Dynamic random noise was overlaid on the visual stimulus. During reliable visual stimulation, the dynamic noise was transparent. (B) Unreliable visual stimulus. During unreliable visual stimulation, the dynamic noise was opaque.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2903191&req=5

Figure 1: The visual stimulus. The visual stimulus consisted of a video of an animated probe (triangular shape) approaching the image of a hand. Three frames of the video are shown. (A) Reliable visual stimulus. Dynamic random noise was overlaid on the visual stimulus. During reliable visual stimulation, the dynamic noise was transparent. (B) Unreliable visual stimulus. During unreliable visual stimulation, the dynamic noise was opaque.
Mentions: Subjects performed a two-alternative forced choice task, deciding whether a touch was delivered to the index finger of the right hand or not. Visual stimuli consisted of a 1.5 s video of an animated triangular probe approaching the tip of the index finger of a photograph of an actor's hand (Figure 1). On “visual touch” trials, the probe contacted the finger at t = 1.0 s and then withdrew. On “visual no-touch” trials, the probe stopped just short of the fingertip at t = 1.0 s and then withdrew.

Bottom Line: When subjects detected viewed and felt touches to the hand, a network of brain areas was active, including visual areas in lateral occipital cortex, somatosensory areas in inferior parietal lobe, and multisensory areas in the intraparietal sulcus (IPS).In agreement with the weighted connection model, the connection weight measured with structural equation modeling between somatosensory cortex and IPS increased for somatosensory-reliable stimuli, and the connection weight between visual cortex and IPS increased for visual-reliable stimuli.This double dissociation of connection strengths was similar to the pattern of behavioral responses during incongruent multisensory stimulation, suggesting that weighted connections may be a neural mechanism for behavioral reliability weighting.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurobiology and Anatomy, University of Texas Health Science Center at Houston Houston, TX, USA.

ABSTRACT
As sensory systems deteriorate in aging or disease, the brain must relearn the appropriate weights to assign each modality during multisensory integration. Using blood-oxygen level dependent functional magnetic resonance imaging of human subjects, we tested a model for the neural mechanisms of sensory weighting, termed "weighted connections." This model holds that the connection weights between early and late areas vary depending on the reliability of the modality, independent of the level of early sensory cortex activity. When subjects detected viewed and felt touches to the hand, a network of brain areas was active, including visual areas in lateral occipital cortex, somatosensory areas in inferior parietal lobe, and multisensory areas in the intraparietal sulcus (IPS). In agreement with the weighted connection model, the connection weight measured with structural equation modeling between somatosensory cortex and IPS increased for somatosensory-reliable stimuli, and the connection weight between visual cortex and IPS increased for visual-reliable stimuli. This double dissociation of connection strengths was similar to the pattern of behavioral responses during incongruent multisensory stimulation, suggesting that weighted connections may be a neural mechanism for behavioral reliability weighting.

No MeSH data available.


Related in: MedlinePlus