Transcranial magnetic stimulation reveals high test–retest reliability for phosphenes but not for suppression of visual perception

ObjectiveTo investigate test–retest reliability of visual cortical excitatory and inhibitory phenomena.MethodsTranscranial magnetic stimulation (TMS) was applied over occipital cortex twice in 22 healthy young adults with at least a one-month interval between both measurements. The test–retest reliability of the phosphenes and TMS-induced suppression of visual perception was assessed using correlation and calculation of the repeatability coefficient.ResultsBoth analyses revealed a high reliability for phosphenes but not for the suppression of visual perception.ConclusionsIt seems likely that the phosphenes may be better used than the TMS-induced suppression of visual perception in experiments which need repeated measurements (e.g., longitudinal studies or studies with pharmacological and non-pharmacological interventions).SignificanceThe study demonstrates a rather limited value of the TMS-induced suppression of visual perception for studies with repeated measurements.

► High retest-reliability and repeatability of phosphenes evoked by the transcranial magnetic stimulation (TMS).
► Low retest-reliability and repeatability of the TMS induced suppression of visual perception.
► Higher value of excitatory and lower of inhibitory phenomena in the visual cortex for studies with repeated measurements.