Article

The leading sense: supramodal control of neurophysiological context by attention.

Cognitive Neuroscience and Schizophrenia Program, Nathan Kline Institute, Orangeburg, New York 10962, USA.
Neuron (impact factor: 14.74). 11/2009; 64(3):419-30. DOI:10.1016/j.neuron.2009.10.014
Source: PubMed

ABSTRACT Attending to a stimulus enhances its neuronal representation, even at the level of primary sensory cortex. Cross-modal modulation can similarly enhance a neuronal representation, and this process can also operate at the primary cortical level. Phase reset of ongoing neuronal oscillatory activity has been shown to be an important element of the underlying modulation of local cortical excitability in both cases. We investigated the influence of attention on oscillatory phase reset in primary auditory and visual cortices of macaques performing an intermodal selective attention task. In addition to responses "driven" by preferred modality stimuli, we noted that both preferred and nonpreferred modality stimuli could "modulate" local cortical excitability by phase reset of ongoing oscillatory activity, and that this effect was linked to their being attended. These findings outline a supramodal mechanism by which attention can control neurophysiological context, thus determining the representation of specific sensory content in primary sensory cortex.

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Keywords

Attending
 
cases
 
findings outline
 
intermodal selective attention task
 
local cortical excitability
 
neuronal representation
 
nonpreferred modality stimuli
 
ongoing neuronal oscillatory activity
 
ongoing oscillatory activity
 
oscillatory phase reset
 
Phase reset
 
preferred
 
preferred modality stimuli
 
primary cortical level
 
specific sensory content
 
stimulus enhances
 
supramodal mechanism
 
underlying modulation
 
visual cortices
 

Peter Lakatos