Title:
Virtual lesion’ in pain research; a study on magnetic stimulation of the
primary motor cortex.
Authors:
Granovsky Y; Liem KS; Weissman-Fogel I; Yarnitsky D; Chistyakov
A;Sinai A.InstitutionGranovsky,Y. Department of Neurology, Rambam Medical Center, Haifa,Israel.Granovsky,Y. Clinical Neurophysiology Laboratory, Technion Faculty of Medicine, Haifa, Israel.
Liem,K S. Faculty of Medicine, University Utrecht, The Netherlands.
Weissman-Fogel,I. Faculty of Social Welfare and Health Sciences,
University of Haifa, Haifa, Israel. Yarnitsky,D. Department of Neurology, Rambam Medical Center, Haifa,Israel. Yarnitsky,D. Clinical Neurophysiology Laboratory, Technion Faculty of Medicine, Haifa, Israel.
Chistyakov,A. Neurosurgery Laboratory, Rambam Medical Center, Haif
a,Israel. Sinai,A. Department of Neurology, Rambam Medical Center, Haifa, Israel. Sinai,A. Neurosurgery Laboratory, Rambam Medical Center, Haifa, Israel.
Title:
Virtual lesion’ in pain research; a study on magnetic stimulation of the
primary motor cortex.
Source:
European Journal of Pain. 20(2):241-9, 2016 Feb.
BACKGROUND:
Virtual lesion’ (‘VL’) is a transient disruption of cortical activity during task performance. It can be induced by single pulses or short trains of transcranial magnetic stimulation (TMS) directed to
functionally relevant brain areas. We applied ‘VL’ methodology of a short
train of TMS given on top of experimental tonic pain, expecting to see
changes in pain scores.
METHODS:
Thirty young healthy subjects (15 women) were assessed with active (‘VL’) or ‘sham’ TMS in different sessions, randomly. In each
session, 30 sec-long contact heat (47.5 degreeC, right forearm) was
applied stand-alone (‘baseline’) and with 5 sec-long 10 Hz-TMS over left
primary motor cortex (M1) starting at 17 sec of the heat stimulation.
RESULTS:
Pain scores decreased after ‘VL’ or ‘sham’ (p < 0.001). Independently of the type of TMS, pain reduction was stronger in women (p= 0.012). A triple Sex x Stimulation type (‘VL’ or ‘sham’) x Condition (‘baseline’ heat pain vs. heat pain with TMS) interaction (p =0.027) indicated stronger pain reduction by ‘VL’ in women (p = 0.008) and not in men (p = 0.78) as compared to ‘baseline’. Pain catastrophizing and perceived stress ratings affected the model (p = 0.010 and p < 0.001, respectively), but without sex differences.
CONCLUSIONS:
This study indicates that interactions between cortical excitability of the motor cortex and nociceptive processing may be gender-related.
Copyright:
2015 European Pain Federation -EFIC
Publication Type:
Journal Article. Randomized Controlled Trial. Research Support, Non-U.S.
Gov’t.
