Magnetoencephalographic study of cortical activity evoked by electrogustatory stimuli.
Electrogustometry is a convenient method to examine taste acuity in clinical situations. Some basic properties of neural activity in the cerebral cortex in response to electrogustatory stimulation were revealed by measuring magnetoencephalography (MEG) signals with a whole-cortex-type system in response to varying intensities of anodal DC currents focally applied to the tongue surface in human subjects. Independent component analysis was used to eliminate stimulus artifacts in MEG signals. Electrogustatory stimulation with intensities of induced electric taste evoked responses bilaterally, mainly in the opercular-insular cortex with a mean onset latency of approximately 350 ms, while subthreshold electrogustatory stimulation induced modest responses in the cortex. Stronger stimulation induced a tingling sensation and elicited large transient responses in both the opercular-insular and somatic sensory cortices. This is the first description of the basic properties of human MEG responses to electrogustatory stimulation.
Yamamoto
Chizuko
C
Department of Behavioral Physiology, Graduate School of Human Sciences, Osaka University, 1-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Takehara
Shiho
S
Morikawa
Kiyomi
K
Nakagawa
Seiji
S
Yamaguchi
Masahiko
M
Iwaki
Sunao
S
Tonoike
Mitsuo
M
Yamamoto
Takashi
T
D000328:Adult; D004558:Electric Stimulation; D004566:Electrodes; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D013003:Somatosensory Cortex / Q000502:physiology*; D013649:Taste / Q000502:physiology*; D014059:Tongue / Q000502:physiology*