Deep brain stimulation (DBS) is an effective treatment for movement disorders, but the mechanisms are unclear. DBS generates inhibition of neurons surrounding the electrode while simultaneously activating the output axons of local neurons. This dual effect does not explain two hallmarks of DBS effectiveness: symptom relief is dependent on using a sufficiently high-stimulation frequency, and clinical effects are analogous to those produced by lesion. The effect of DBS at different frequencies on the output of intrinsically active neurons was studied using computational models. DBS produced frequency-dependent modulation of the variability of neuronal output, and above a critical frequency stimulation resulted in regular output with zero variance. The resulting loss of information offers an explanation for the two hallmarks of DBS effectiveness.
Copyright 2004 Lippincott Williams and Wilkins