Abstract
Cortical excitation/inhibition (E/I) imbalances contribute to various clinical symptoms observed in autism spectrum disorder (ASD). However, the detailed pathophysiologic underpinning of E/I imbalance remains uncertain. Transcranial magnetic stimulation (TMS) motor-evoked potentials (MEP) are a non-invasive tool for examining cortical inhibition in ASD. Here, we conducted a systematic review on TMS neurophysiology in motor cortex (M1) such as MEPs and short-interval intracortical inhibition (SICI) between individuals with ASD and controls. Out of 538 initial records, we identified six articles. Five studies measured MEP, where four studies measured SICI. There were no differences in MEP amplitudes between the two groups, whereas SICI was likely to be reduced in individuals with ASD compared with controls. Notably, SICI largely reflects GABA(A) receptor-mediated function. Conversely, other magnetic resonance spectroscopy and postmortem methodologies assess GABA levels. The present review demonstrated that there may be neurophysiological deficits in GABA receptor-mediated function in ASD. In conclusion, reduced GABAergic function in the neural circuits could underlie the E/I imbalance in ASD, which may be related to the pathophysiology of clinical symptoms of ASD. Therefore, a novel treatment that targets the neural circuits related to GABA(A) receptor-mediated function in regions involved in the pathophysiology of ASD may be promising.
| Original language | English |
|---|---|
| Article number | 110 |
| Journal | Translational psychiatry |
| Volume | 9 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 2019 Dec 1 |
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ASJC Scopus subject areas
- Psychiatry and Mental health
- Cellular and Molecular Neuroscience
- Biological Psychiatry
Cite this
Motor cortex excitability and inhibitory imbalance in autism spectrum disorder assessed with transcranial magnetic stimulation : a systematic review. / Masuda, Fumi; Nakajima, Shinichiro; Miyazaki, Takahiro; Yoshida, Kazunari; Tsugawa, Sakiko; Wada, Masataka; Ogyu, Kamiyu; Croarkin, Paul E.; Blumberger, Daniel M.; Daskalakis, Zafiris J.; Mimura, Masaru; Noda, Yoshihiro.
In: Translational psychiatry, Vol. 9, No. 1, 110, 01.12.2019.Research output: Contribution to journal › Review article
}
TY - JOUR
T1 - Motor cortex excitability and inhibitory imbalance in autism spectrum disorder assessed with transcranial magnetic stimulation
T2 - a systematic review
AU - Masuda, Fumi
AU - Nakajima, Shinichiro
AU - Miyazaki, Takahiro
AU - Yoshida, Kazunari
AU - Tsugawa, Sakiko
AU - Wada, Masataka
AU - Ogyu, Kamiyu
AU - Croarkin, Paul E.
AU - Blumberger, Daniel M.
AU - Daskalakis, Zafiris J.
AU - Mimura, Masaru
AU - Noda, Yoshihiro
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Cortical excitation/inhibition (E/I) imbalances contribute to various clinical symptoms observed in autism spectrum disorder (ASD). However, the detailed pathophysiologic underpinning of E/I imbalance remains uncertain. Transcranial magnetic stimulation (TMS) motor-evoked potentials (MEP) are a non-invasive tool for examining cortical inhibition in ASD. Here, we conducted a systematic review on TMS neurophysiology in motor cortex (M1) such as MEPs and short-interval intracortical inhibition (SICI) between individuals with ASD and controls. Out of 538 initial records, we identified six articles. Five studies measured MEP, where four studies measured SICI. There were no differences in MEP amplitudes between the two groups, whereas SICI was likely to be reduced in individuals with ASD compared with controls. Notably, SICI largely reflects GABA(A) receptor-mediated function. Conversely, other magnetic resonance spectroscopy and postmortem methodologies assess GABA levels. The present review demonstrated that there may be neurophysiological deficits in GABA receptor-mediated function in ASD. In conclusion, reduced GABAergic function in the neural circuits could underlie the E/I imbalance in ASD, which may be related to the pathophysiology of clinical symptoms of ASD. Therefore, a novel treatment that targets the neural circuits related to GABA(A) receptor-mediated function in regions involved in the pathophysiology of ASD may be promising.
AB - Cortical excitation/inhibition (E/I) imbalances contribute to various clinical symptoms observed in autism spectrum disorder (ASD). However, the detailed pathophysiologic underpinning of E/I imbalance remains uncertain. Transcranial magnetic stimulation (TMS) motor-evoked potentials (MEP) are a non-invasive tool for examining cortical inhibition in ASD. Here, we conducted a systematic review on TMS neurophysiology in motor cortex (M1) such as MEPs and short-interval intracortical inhibition (SICI) between individuals with ASD and controls. Out of 538 initial records, we identified six articles. Five studies measured MEP, where four studies measured SICI. There were no differences in MEP amplitudes between the two groups, whereas SICI was likely to be reduced in individuals with ASD compared with controls. Notably, SICI largely reflects GABA(A) receptor-mediated function. Conversely, other magnetic resonance spectroscopy and postmortem methodologies assess GABA levels. The present review demonstrated that there may be neurophysiological deficits in GABA receptor-mediated function in ASD. In conclusion, reduced GABAergic function in the neural circuits could underlie the E/I imbalance in ASD, which may be related to the pathophysiology of clinical symptoms of ASD. Therefore, a novel treatment that targets the neural circuits related to GABA(A) receptor-mediated function in regions involved in the pathophysiology of ASD may be promising.
UR - http://www.scopus.com/inward/record.url?scp=85062583629&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85062583629&partnerID=8YFLogxK
U2 - 10.1038/s41398-019-0444-3
DO - 10.1038/s41398-019-0444-3
M3 - Review article
C2 - 30846682
AN - SCOPUS:85062583629
VL - 9
JO - Translational Psychiatry
JF - Translational Psychiatry
SN - 2158-3188
IS - 1
M1 - 110
ER -