Hemodynamic changes after rTMS

Share on facebook
Share on twitter
Share on google
Share on linkedin
Share on email
Share on print
fNIRS

Comparison of hemodynamic changes after repetitive transcranial magnetic stimulation over the anatomical hand knob and hand motor hotspot: A functional near-infrared spectroscopy study.

Abstract
BACKGROUND: Low-frequency rTMS can induce upregulation of excitability in the contralateral hemisphere by interhemispheric interaction.
OBJECTIVE: The aim of this study was to compare the effects of interhemispheric modulation on hemodynamic changes after applying low-frequency rTMS over the anatomical hand knob (HK) and the hand motor hotspot (hMHS) in the dominant motor cortex.
METHODS: Ten healthy right-handed participants without a history of neurological or psychiatric symptoms (five males; 29.8±2.8 years) participated in this single-blind, randomized, cross-over study. rTMS was applied under three conditions over the dominant (left) hemisphere for 20 minutes: 1) 1 Hz rTMS stimulation on the HK (HK-rTMS), 2) 1 Hz rTMS stimulation on the hMHS (hMHS-rTMS), and 3) sham stimulation (Sham-rTMS). For all participants, functional near-infrared spectroscopy (fNIRS) was applied for measurement of cerebral oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) concentration over the non-dominant (right) hemisphere during a serial reaction time task (SRTT) with the non-dominant (left) hand before and after each condition.
RESULTS: The average coordinates of the hMHS (x = - 39.60 mm, y = - 17.11 mm, z = 66.40 mm) were anterior and lateral to the HK (x = - 36.72 mm, y = - 28.87 mm, z = 56.41 mm). In fNIRS time-series analysis, the integral value of oxyHb wassignificantly increased over the motor cortical region of the non-dominant hemisphere after the hMHS-rTMS compared with Sham-rTMS. The HK-rTMS also showed slight increment of oxyHb concentration but without statistical significance. The SPM group analysis showed greater magnitude of the activity in hMHS-rTMS than that of HK-rTMS after stimulation (p <  0.05).
CONCLUSIONS: These results demonstrated an interhemispheric modulation effect of hemodynamic changes by 1 Hz rTMS. The hMHS produced a more robust modulation effect of 1 Hz rTMS on the contralateral hemisphere than did the HK. Therefore, the rTMS can be considered a better stimulation target than the HK.

PMID: 33285650 [PubMed – as supplied by publisher]

Restor Neurol Neurosci. 2020 Nov 28;:

Authors: Kim J, Kim H, Lee J, Lee HJ, Na Y, Chang WH, Kim YH

Join Our Newsletter


Mike

Mike

Comments?