TY - JOUR
T1 - Changes in intracortical inhibition and clinical symptoms after STN-DBS in Parkinson's disease
AU - Kobayashi, Masahito
AU - Ohira, Takayuki
AU - Mihara, Ban
AU - Fujimaki, Takamitsu
N1 - Funding Information:
This work was partly supported by JSPS KAKENHI # 23592105 . We would like to express our gratitude to Professor Masayuki Hirukawa for his valuable guidance in the statistical analysis.
PY - 2016/4/1
Y1 - 2016/4/1
N2 - Objectives: To examine effects of subthalamic nucleus deep brain stimulation (STN-DBS) on intracortical inhibition in Parkinson's disease (PD) and the correlation between intracortical inhibition and clinical symptoms after alteration of STN-DBS status. Methods: Nine PD patients treated by STN-DBS were compared with eight age-matched controls. Antiparkinsonian medication was withdrawn 12 h before the study. Short-interval intracortical inhibition (SICI) with a 3-ms interval and silent period (SP) were examined using transcranial magnetic stimulation. SP duration, SICI and motor symptoms (rigidity and tremor) were evaluated with STN-DBS ON, and over 120 min during STN-DBS OFF. Results: Even during STN-DBS, PD patients showed a shortened SP and reduced SICI relative to normal controls. SICI decreased further throughout STN-DBS OFF, resulting in facilitation rather than inhibition; SP shortened only after 120 min STN-DBS OFF. Both rigidity and tremor worsened throughout STN-DBS OFF, with a time course similar to SICI. Conclusion: Even during STN-DBS, both SICI and SP in PD patients remain impaired without medication. Changes in SICI, but not SP, show a time course similar to those of motor symptoms. Significance: The dissimilarity of SICI and SP changes suggests differences in mediation of inhibitory mechanisms and/or superimposition of exaggerated intracortical facilitation on SICI.
AB - Objectives: To examine effects of subthalamic nucleus deep brain stimulation (STN-DBS) on intracortical inhibition in Parkinson's disease (PD) and the correlation between intracortical inhibition and clinical symptoms after alteration of STN-DBS status. Methods: Nine PD patients treated by STN-DBS were compared with eight age-matched controls. Antiparkinsonian medication was withdrawn 12 h before the study. Short-interval intracortical inhibition (SICI) with a 3-ms interval and silent period (SP) were examined using transcranial magnetic stimulation. SP duration, SICI and motor symptoms (rigidity and tremor) were evaluated with STN-DBS ON, and over 120 min during STN-DBS OFF. Results: Even during STN-DBS, PD patients showed a shortened SP and reduced SICI relative to normal controls. SICI decreased further throughout STN-DBS OFF, resulting in facilitation rather than inhibition; SP shortened only after 120 min STN-DBS OFF. Both rigidity and tremor worsened throughout STN-DBS OFF, with a time course similar to SICI. Conclusion: Even during STN-DBS, both SICI and SP in PD patients remain impaired without medication. Changes in SICI, but not SP, show a time course similar to those of motor symptoms. Significance: The dissimilarity of SICI and SP changes suggests differences in mediation of inhibitory mechanisms and/or superimposition of exaggerated intracortical facilitation on SICI.
KW - Intracortical inhibition
KW - Parkinson's disease
KW - Subthalamic nucleus deep brain stimulation
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U2 - 10.1016/j.clinph.2016.01.022
DO - 10.1016/j.clinph.2016.01.022
M3 - Article
C2 - 26971486
AN - SCOPUS:84958568877
SN - 1388-2457
VL - 127
SP - 2031
EP - 2037
JO - Clinical Neurophysiology
JF - Clinical Neurophysiology
IS - 4
ER -