Comparing endoscopic systems on two simulated tasks.

Endoscopes are slender instruments for performing medical procedures through small incisions or natural body orifices. Three experiments examined the performance effects of various endoscope systems when naive participants executed tasks in a bladder-like environment. The systems involved a direct endoscope, requiring the user to look through a lens at the outer part of the endoscope, and a video endoscope that picks up the image via a camera attached to the endoscope and displays it on a video monitor.

On the role of the SMA in the discrete sequence production task: a TMS study. Transcranial Magnetic Stimulation.

Participants practiced two discrete six-key sequences for a total of 420 trials. The 1 x 6 sequence had a unique order of key presses while the 2 x 3 sequence involved repetition of a three-key segment. Both sequences showed a long interkey interval halfway the sequence indicating hierarchical sequence control in that not only the 2 x 3 but also the 1 x 6 sequence was executed as two successive motor chunks.