Multisensory auditory–somatosensory interactions in early cortical processing revealed by high-density electrical mapping

• Published in: Brain research. Cognitive brain research Vol. 10; no. 1; pp. 77 - 83
• Main Authors: Foxe, John J, Morocz, Istvan A, Murray, Micah M, Higgins, Beth A, Javitt, Daniel C, Schroeder, Charles E
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2000; Elsevier Science
• Subjects: Acoustic Stimulation; Adult; AEP; Auditory cortex; Auditory Cortex - physiology; Behavioral psychophysiology; Binding; Biological and medical sciences; Brain Mapping - methods; Crossmodal integration; Electric Stimulation; Electroencephalography; Electrophysiology; ERP; Event-related potential; Evoked Potentials, Auditory - physiology; Evoked Potentials, Somatosensory - physiology; Female; Fundamental and applied biological sciences. Psychology; High-density mapping; Human; Humans; Male; Median Nerve - physiology; Multisensory integration; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Scalp - physiology; SEP; Somatosensory cortex; Somatosensory Cortex - physiology; Time Factors; Event-related potential; Human; Binding; Somatosensory cortex; ERP; Crossmodal integration; High-density mapping; Sensory systems; Multisensory integration; AEP; Auditory cortex; SEP; Information integration; Somesthesia; Central nervous system; Electrophysiology; Cognition; Somesthetic pathway; Perception; Auditory pathway; Intermodal perception; Event evoked potential; Brain (vertebrata)
• ISSN: 0926-6410
• DOI: 10.1016/S0926-6410(00)00024-0

We investigated the time-course and scalp topography of multisensory interactions between simultaneous auditory and somatosensory stimulation in humans. Event-related potentials (ERPs) were recorded from 64 scalp electrodes while subjects were presented with auditory-alone stimulation (1000-Hz tones), somatosensory-alone stimulation (median nerve electrical pulses), and simultaneous auditory–somatosensory (AS) combined stimulation. Interaction effects were assessed by comparing the responses to combined stimulation with the algebraic sum of responses to the constituent auditory and somatosensory stimuli when they were presented alone. Spatiotemporal analysis of ERPs and scalp current density (SCD) topographies revealed AS interaction over the central/postcentral scalp which onset at approximately 50 ms post-stimulus presentation. Both the topography and timing of these interactions are consistent with multisensory integration early in the cortical processing hierarchy, in brain regions traditionally held to be unisensory.