Title
Steady-state responses in MEG demonstrate information integration within but not across the auditory and visual senses.
Abstract
To form a unified percept of our environment, the human brain integrates information within and across the senses. This MEG study investigated interactions within and between sensory modalities using a frequency analysis of steady-state responses that are elicited time-locked to periodically modulated stimuli. Critically, in the frequency domain, interactions between sensory signals are indexed by crossmodulation terms (i.e. the sums and differences of the fundamental frequencies). The 3×2 factorial design, manipulated (1) modality: auditory, visual or audiovisual (2) steady-state modulation: the auditory and visual signals were modulated only in one sensory feature (e.g. visual gratings modulated in luminance at 6Hz) or in two features (e.g. tones modulated in frequency at 40Hz & amplitude at 0.2Hz). This design enabled us to investigate crossmodulation frequencies that are elicited when two stimulus features are modulated concurrently (i) in one sensory modality or (ii) in auditory and visual modalities. In support of within-modality integration, we reliably identified crossmodulation frequencies when two stimulus features in one sensory modality were modulated at different frequencies. In contrast, no crossmodulation frequencies were identified when information needed to be combined from auditory and visual modalities. The absence of audiovisual crossmodulation frequencies suggests that the previously reported audiovisual interactions in primary sensory areas may mediate low level spatiotemporal coincidence detection that is prominent for stimulus transients but less relevant for sustained SSR responses. In conclusion, our results indicate that information in SSRs is integrated over multiple time scales within but not across sensory modalities at the primary cortical level.
Year
DOI
Venue
2012
10.1016/j.neuroimage.2012.01.114
NeuroImage
Keywords
Field
DocType
MEG,Multisensory integration,Crossmodal,Audiovisual,Steady-state responses,Crossmodulation frequencies
Crossmodal,Neuroscience,Multisensory integration,Primary sensory areas,Psychology,Cognitive psychology,Speech recognition,Stimulus (physiology),Coincidence detection in neurobiology,Sensory system,Stimulus modality,Percept
Journal
Volume
Issue
ISSN
60
2
1053-8119
Citations 
PageRank 
References 
8
0.67
14
Authors
6
Name
Order
Citations
PageRank
Anette S. Giani180.67
Erick Ortiz2121.48
Paolo Belardinelli3234.20
Mario Kleiner4745.75
Hubert Preissl56619.36
U. Noppeney612933.46