As discussed previously in "Microelectrode Recording (MER)", use of the microelectrode also allows us to pass current (5-100uA) at a very high frequency (300Hz) through the microelectrode in order to better define our target. For example, microstimulation can demonstrate tremor arrest when at target (see videos).

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    Microstimulation delivered during the buzzing sound demonstrates
    tremor effect in the upper extremity in the left video and in the foot
    in the right video.
If we are too close to sensory pathways during stimulation (Vc, medial lemniscus, or optic tract), a patient may feel tingling in a part of the body at very low thresholds or have a visual phenomenon (see videos). If weare too close to motor pathways during stimulation (internal capsule), a patient may experience muscle contractions on one side of the body.

          
    Microstimulation applied during the buzzing sound causes tingling
    sensations in the upper extremity in the left video (sensory thalamus)
    and throughout the entire right side of the body in the right video
    (medial lemniscus).

The Johns Hopkins Parkinson's Disease
and Movement Disorders Center
The Johns Hopkins Hospital Outpatient Center, Room 5064
601 N. Caroline Street | Baltimore, MD 21287
410-955-8795 (tel) | 410-614-1302 (fax)
hopkinsdbs@jhmi.edu

Acknowledgements:
This website was created by Rebecca Dunlop, Ira Garonzik,
Stephen Grill, Fred Lenz, Shinji Ohara, Lance Rowland, and Cecilia Young.