title: Roles of the pre-SMA and rIFG in conditional stopping revealed by transcranial magnetic stimulation.
abstract: Although both the presupplementary motor area (pre-SMA) and the right inferior frontal gyrus (rIFG) have been demonstrated to be critical for response inhibition, there is still considerable disagreement over the roles they play in the process. In the present study, we investigated the causal relations of the pre-SMA and the rIFG in a conditional stop-signal task by applying offline theta-burst transcranial magnetic stimulation. The task introduced a continue condition, which requires the same motor response as in a go trial but captures attention as in a stop trial. We found great individual differences in the amount of slowing on continue trials. Temporary suppression of pre-SMA activity prolonged the continue RT in participants who slowed little in response to continue trials, whereas disruption of the rIFG did not lead to significant changes in performance irrespective of the degree of slowing. Our results contribute to the understanding of the role of the pre-SMA by providing causal evidence that it is involved in response slowing on continue trials during conditional stopping, and it is likely that its efficiency in updating motor planning and reinitiating an inhibited response was associated with the amount of slowing.
authors: Institute of Cognitive Neuroscience, National Central University, Taoyuan City 320, Taiwan.
authors: Hon Wah
authors: HW
authors: Lee
authors: Institute of Cognitive Neuroscience, National Central University, Taoyuan City 320, Taiwan.
authors: Ming-Shan
authors: MS
authors: Lu
authors: Department and Graduate Institute of Criminology, National Chung Cheng University, Chiayi County 621, Taiwan.
authors: Chiao-Yun
authors: CY
authors: Chen
authors: Institute of Cognitive Neuroscience, National Central University, Taoyuan City 320, Taiwan; Department of Psychology, Goldsmiths, University of London, New Cross, London, UK.
authors: Neil G
authors: NG
authors: Muggleton
authors: Brain and Consciousness Research Center, Taipei Medical University-Shuang-Ho Hospital, New Taipei City 235, Taiwan.
authors: Tzu-Yu
authors: TY
authors: Hsu
authors: Institute of Cognitive Neuroscience, National Central University, Taoyuan City 320, Taiwan; Brain Research Center, National Central University, Taoyuan City 320, Taiwan. Electronic address: chijuan@cc.ncu.edu.tw.
authors: Chi-Hung
authors: CH
authors: Juan
mesh_terms: D000328:Adult; D001931:Brain Mapping; D056344:Executive Function / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology*; D013826:Theta Rhythm / Q000502:physiology*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D055815:Young Adult
keywords: Conditional stop-signal task; Inhibitory control; Pre-supplementary motor area; Right inferior prefrontal gyrus; Transcranial magnetic stimulation