Title
Neuromodulation of early multisensory interactions in the visual cortex.
Abstract
Merging information derived from different sensory channels allows the brain to amplify minimal signals to reduce their ambiguity, thereby improving the ability of orienting to, detecting, and identifying environmental events. Although multisensory interactions have been mostly ascribed to the activity of higher-order heteromodal areas, multisensory convergence may arise even in primary sensory-specific areas located very early along the cortical processing stream. In three experiments, we investigated early multisensory interactions in lower-level visual areas, by using a novel approach, based on the coupling of behavioral stimulation with two noninvasive brain stimulation techniques, namely, TMS and transcranial direct current stimulation (tDCS). First, we showed that redundant multisensory stimuli can increase visual cortical excitability, as measured by means of phosphene induction by occipital TMS; such physiological enhancement is followed by a behavioral facilitation through the amplification of signal intensity in sensory-specific visual areas. The more sensory inputs are combined (i.e., trimodal vs. bimodal stimuli), the greater are the benefits on phosphene perception. Second, neuroelectrical activity changes induced by tDCS in the temporal and in the parietal cortices, but not in the occipital cortex, can further boost the multisensory enhancement of visual cortical excitability, by increasing the auditory and tactile inputs from temporal and parietal regions, respectively, to lower-level visual areas.
Year
DOI
Venue
2013
10.1162/jocn_a_00347
Cognitive Neuroscience, Journal of
Keywords
Field
DocType
behavioral stimulation,multisensory interaction,visual cortical excitability,early multisensory interaction,multisensory enhancement,redundant multisensory stimulus,multisensory convergence,visual cortex,cortical processing stream,lower-level visual area,noninvasive brain stimulation technique,sensory-specific visual area
Neuroscience,Phosphene,Visual cortex,Brain stimulation,Psychology,Cognitive psychology,Neuromodulation,Stimulus (physiology),Sensory system,Transcranial direct-current stimulation,Perception
Journal
Volume
Issue
ISSN
25
5
1530-8898
Citations 
PageRank 
References 
3
0.57
5
Authors
4
Name
Order
Citations
PageRank
Silvia Convento130.57
Giuseppe Vallar2152.77
Chiara Galantini330.57
Nadia Bolognini4256.31