Oscillatory beta activity predicts response speed during a multisensory audiovisual reaction time task: a high-density electrical mapping study.

TY - JOUR

T1 - Oscillatory beta activity predicts response speed during a multisensory audiovisual reaction time task: a high-density electrical mapping study.

AU - Senkowski, Daniel

AU - Molholm, Sophie

AU - Gomez-Ramirez, Manuel

AU - Foxe, John J

PY - 2006

Y1 - 2006

N2 - Bisensory redundant targets are processed faster than the respective unisensory target stimuli alone as evidenced by substantially faster reaction times (RTs). This multisensory RT facilitation has been interpreted as an expression of integrative processing between the different sensory modalities. However, the neuronal mechanisms underlying the RT facilitation effect are not well understood. Oscillatory responses in the beta frequency range (13-30 Hz) have been related to sensory-motor processing. Here, we investigated whether modulation of beta responses might also underlie the faster RTs seen for multisensory stimuli. Using high-density electrical mapping, we explored the association between early (50-170 ms) multisensory processing in the evoked beta response and RTs recorded during a simple RT task. Subjects were instructed to indicate the appearance of any stimulus in a stream of auditory-alone (A), visual-alone (V), and multisensory (AV) stimuli by a button press. Beta responses were analyzed using Morlet wavelet transformations. Multisensory interactions were found over frontal, occipital, central, and sensory-motor regions. Critically, beta activity correlated with mean RTs over all stimulus types. Significant negative correlations were found for frontal, occipital, and sensory-motor scalp regions. We conclude that the association between oscillatory beta activity and integrative multisensory processing is directly linked to multisensory RT facilitation effects.

AB - Bisensory redundant targets are processed faster than the respective unisensory target stimuli alone as evidenced by substantially faster reaction times (RTs). This multisensory RT facilitation has been interpreted as an expression of integrative processing between the different sensory modalities. However, the neuronal mechanisms underlying the RT facilitation effect are not well understood. Oscillatory responses in the beta frequency range (13-30 Hz) have been related to sensory-motor processing. Here, we investigated whether modulation of beta responses might also underlie the faster RTs seen for multisensory stimuli. Using high-density electrical mapping, we explored the association between early (50-170 ms) multisensory processing in the evoked beta response and RTs recorded during a simple RT task. Subjects were instructed to indicate the appearance of any stimulus in a stream of auditory-alone (A), visual-alone (V), and multisensory (AV) stimuli by a button press. Beta responses were analyzed using Morlet wavelet transformations. Multisensory interactions were found over frontal, occipital, central, and sensory-motor regions. Critically, beta activity correlated with mean RTs over all stimulus types. Significant negative correlations were found for frontal, occipital, and sensory-motor scalp regions. We conclude that the association between oscillatory beta activity and integrative multisensory processing is directly linked to multisensory RT facilitation effects.

M3 - SCORING: Zeitschriftenaufsatz

VL - 16

SP - 1556

EP - 1565

JO - CEREB CORTEX

JF - CEREB CORTEX

SN - 1047-3211

IS - 11

M1 - 11

ER -