At that time, a battery of neuropsychological measures was administered with and without bilateral stimulation. Without stimulation, the patient demonstrated declines of greater than 1 SD on measures of verbal fluency and verbal recall compared to when the stimulators were active. Responses to mood rating scales also indicated greater subjective distress without stimulation. Results are discussed in the context of previous studies of the effects of thalamic stimulation on neurocognitive functioning. Copyright 2000 Academic Press.
Stimulation is thought to be as effective as thalamotomy but to have fewer complications.
We examined the effects of these two procedures on the functional abilities of patients with drug-resistant tremor due to Parkinson's disease, essential tremor, or multiple sclerosis. The primary outcome measure was the change in functional abilities six months after surgery, as measured by the Frenchay Activities Index. Scores for this index can range from 0 to 60, with higher scores indicating better function. Secondary outcome measures were the severity of tremor, the number of adverse effects, and patients' assessment of the outcome. Tremor was suppressed completely or almost completely in 27 of 34 patients in the thalamotomy group and in 30 of 33 patients in the thalamic-stimulation group.