Journal: PLOS ONE

Article Title: The effects of verbal and spatial working memory on short- and long-latency sensorimotor circuits in the motor cortex

doi: 10.1371/journal.pone.0302989

Figure Lengend Snippet: The memory set was presented after a 500ms pre-trial period. A group of two or six items appeared. There were twelve locations where an object could appear on a given trial. The inset demonstrates all possible stimuli and locations for the verbal and spatial task. In any single trial, one TMS stimulus alone (unconditioned) or one TMS stimulus preceded by electrical stimulation of the median nerve (conditioned) was delivered during the latter half of the maintenance period. To minimize anticipation of the TMS stimulus, the timing of TMS stimulus varied between 1500, 1750, 2000, 2250, or 2500 ms using a rectangular distribution. The TMS stimulus was triggered by the working memory program using a digital output trigger sent to the digital trigger input on the Magstim 200 2 stimulator via a BNC connection on the Magstim Stimulator Interface Module. For conditioned trials, a separate digital output trigger was sent to a digital trigger input on the SD9 constant current stimulator. The digital trigger to the peripheral stimulator preceded the digital trigger to the TMS stimulator by either 21 ms or 200 ms.

Article Snippet: Electrical stimulation was delivered using an SD9 constant current high voltage stimulator (Grass Astro-Med, West Warwick, RI).

Techniques: