Pulse configuration-dependent effects of repetitive transcranial magnetic stimulation on visual perception

2002 | journal article. A publication with affiliation to the University of Göttingen.

Jump to: Cite & Linked | Documents & Media | Details | Version history

Cite this publication

​Pulse configuration-dependent effects of repetitive transcranial magnetic stimulation on visual perception​
Antal, A.; Kincses, T. Z.; Nitsche, M. A.; Bartfai, O.; Demmer, I. ; Sommer, M. & Paulus, W. J.​ (2002) 
Neuroreport13(17) pp. 2229​-2233​.​ DOI: https://doi.org/10.1097/00001756-200212030-00013 

Documents & Media

License

GRO License GRO License

Details

Authors
Antal, Andrea; Kincses, T. Z.; Nitsche, M. A.; Bartfai, O.; Demmer, Iris ; Sommer, M.; Paulus, Walter J.
Abstract
Transcranial magnetic stimulation (TMS) is a noninvasive technique for direct stimulation of the neocortex. In the last two decades it is successfully applied in the study of motor and sensory physiology TMS uses the indirect induction of electrical fields in the brain generated by intense changes of magnetic fields applied to the scalp. It encompasses two widely used waveform configurations: monophasic magnetic pulses induce a single current in the brain while biphasic pulses induce at least two currents of inverse direction. As has been shown for the motor cortex, efficacy of repetitive transcranial magnetic stimulation (rTMS) may depend on pulse configuration. In order to clarify this question with regard to visual perception, static contrast sensitivities (sCS) were evaluated before, during, immediately after and 10 minutes after monophasic and biphasic low frequency (1 Hz) rTMS applied to the occipital cortex of 15 healthy subjects. The intensity of stimulation was the phosphene threshold of each individual subject. Using 4c/d spatial frequency, significant sCS loss was found during and immediately after 10 min of monophasic stimulation, while biphasic stimulation resulted in no significant effect. Ten minutes after the end of stimulation, the sCS values were at baseline level again. However, reversed current flow direction resulted in an increased efficacy of biphasic and decreased efficacy of monophasic stimulation. Our results are in agreement with previous findings showing that primary visual functions, such as contrast detection, can be transiently altered by low frequency transcranial magnetic stimulation. However the effect of modulation significantly depends on the current waveform and direction.
Issue Date
2002
Status
published
Publisher
Lippincott Williams & Wilkins
Journal
Neuroreport 
ISSN
0959-4965

Reference

Citations


Social Media