N30 wave amplitude of somatosensory evoked potentials from median nerve in Parkinson's disease: a pharmacological study.

We studied N20 and N30 waves of Somatosensory Evoked Potentials from median nerve stimulation in different pharmacological conditions. N30 wave amplitude was decreased in 33 parkinsonians without therapy in comparison with a group of age-matched normal subjects. In a group of 19 parkinsonians, N30 wave amplitude was significantly augmented during apomorphine infusion and less evidently, but still significantly, during chronic 1-dopa therapy. The administration of an oral dose of haloperidol in 11 normals did not affect significantly the studied parameters. The infusion of apomorphine in 6 psychotic patients with extrapyramidal symptoms secondary to long-term treatment with neuroleptics, determined, together with a clear-cut clinical amelioration, a significant increase of N30 amplitude and N30/N20 ratio. Possible pathophysiological hypothesis of such electrophysiological modifications are discussed.

Electrophysiological (BAEPs) changes in subacute sclerosing panencephalitis.

Over a period of time, the authors have studied a case of subacute sclerosing panencephalitis (SSPE), by means of brainstem auditory evoked potentials (BAEPs). The observed abnormalities of the conduction time along the early auditory pathways appeared to be related to the clinical picture; in fact, during periods of transitory clinical improvement these abnormalities were less evident. In addition, the encountered electrophysiological alterations consisted of a marked pathologic increase in the III-V interpeak latencies. The authors suggest that the BAEPs findings in their case could have been influenced by either unfavourable endogenous conditions (edema, electrolyte changes, etc.) or CNS segmental lesions due to focal viral distribution.

Effectiveness of bornaprine on parkinsonian tremor.

The effectiveness of Bornaprine on parkinsonian tremor was evaluated in a single-blind study of medium-term treatment. 25 patients were treated with rising doses of Bornaprine per os, one week at each dose-level. The dose at which Bornaprine was most effective was 8 mg daily and its action at this dose was mild but statistically significant. The drug was generally well tolerated in patients with idiopathic parkinsonism, but transient confusion developed in a few patients with secondary parkinsonism.

Electrophysiological (CNV) analysis of personality traits under stress.

Contingent negative variation (CNV) recordings were performed in 55 healthy volunteers under stress condition (experimentally induced pain). A total of 20 subjects were included in the control group (no painful administration). In the tested group (n = 35) the painful stimulus was delivered before S1, between S2 and S1, and before S2. In the control group there were no changes in CNV parameters. Conversely, among the tested group a positive correlation was found between CNV values (whenever the painful stimulus was administered before S1 as well as before S2) and the highest scores in the State Trait Anxiety Inventory X 2 test. In addition, all individuals displayed the appearance of a positive deflection with a latency of about 300 ms from S2 when the experimental stress was given before S2. Furthermore, the postimperative negative variation (PINV) appeared in 13 out of 35 subjects. There was a strong correlation between the latter electrophysiological phenomenon and the Nowlis test. Our findings suggest that CNV study is useful for the investigation of personality traits in human beings under stress conditions.