title: Deactivation and activation of left frontal lobe during and after low-frequency repetitive transcranial magnetic stimulation over right prefrontal cortex: a near-infrared spectroscopy study.
abstract: The effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) over the right frontal lobe on the function of the left frontal lobe were examined by near-infrared spectroscopy (NIRS) in eleven healthy subjects. rTMS applied 5cm anterior to the motor cortex at 1 Hz and approximately 50% of the motor threshold intensity (MT) for 60 s resulted in a significantly larger decrease in the concentration of oxygenated hemoglobin ([oxy-Hb]) during the stimulation period followed by a significantly larger increase in [oxy-Hb] and a smaller decrease in the concentration of deoxygenated hemoglobin ([deoxy-Hb]) during the poststimulation baseline period than sham stimulation. These findings are interpreted as demonstrating the deactivation and activation of the left frontal cortex during and after rTMS of the right frontal cortex, respectively. If replicated in depressed patients, NIRS can be employed for monitoring rTMS effects as brain [Hb] changes in vivo, and may be helpful for determining therapeutic parameters of rTMS for individual patients.
authors.affiliation: Department of Psychiatry and Human Behavior, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Hanaoka
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Aoyama
authors.forename: Masaki
authors.initials: M
authors.lastname: Kameyama
authors.forename: Masato
authors.initials: M
authors.lastname: Fukuda
authors.forename: Masahiko
authors.initials: M
authors.lastname: Mikuni
mesh_terms: D000328:Adult; D002560:Cerebrovascular Circulation / Q000502:physiology; D003866:Depressive Disorder / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D005625:Frontal Lobe / Q000033:anatomy & histology / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology*; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000033:anatomy & histology / Q000502:physiology; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology; D011237:Predictive Value of Tests; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000502:physiology*; D011930:Reaction Time; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
chemical_list: D006454:Hemoglobins