Sybille Spieker

Memory and Skill Acquisition in Parkinson's Disease and Frontal Lobe Dysfunction

Animal experiments and human neuropsychological studies have provided evidence for the hypothesis that skill acquisition may be regulated by the basal ganglia. In the present studies, perceptual and cognitive skill acquisition as well as a number of explicit verbal memory functions were investigated in patients in early and more advanced stages of Parkinsons disease (PD) and in patients with frontal lobe lesions. Patients in more advanced stages of PD were impaired at cognitive skill acquisition as well as during recall conditions that involved active semantic organisation of the stimulus material. Similar explicit memory deficits were present in frontally lesioned patients. PD patients with unilateral symptoms showed a selective impairment in acquiring a cognitive skill. Perceptual skill acquisition was preserved in all groups. The overall pattern of memory impairment in PD is largely consistent with dysfunction of fronto-striatal circuitry.

Fractal dimension of sustained vowel productions in neurological dysphonias: An acoustic and electroglottographic analysis

In order to investigate whether nonlinear methods of signal analysis provide a measure of phonatory irregularities in neurogenic voice disorders, the present study computed the fractal dimension (D) both of the electroglottographic (EGG) and the acoustic signal of sustained vowel productions obtained from patients with Parkinsons disease (PD) and cerebellar atrophy (CA). Compared with normal speakers, the female PD group as well as the male and female CA patients showed an increased dimension (D) of the EGG. The dimensional complexity of the acoustic signal largely depended on vowel type. Furthermore, the dimension of the acoustic signal was reduced in male PD patients as compared to the respective controls.

Tremorlytic activity of budipine in Parkinson's disease

In order to objectively quantify the tremorlytic activity of budipine in Parkinsons disease (PD) we performed longterm tremor recordings in a subset of patients enrolled in two clinical trials. Eleven PD patients with marked tremor participating in an open-label study underwent longterm recording before and during medication. Nine patients completed the study. Tremor occurrence was reduced from 52 +/- 18.6% to 34.7 +/- 19.3% (p < 0.05); tremor intensity decreased from 15.3 +/- 4.8 (SNR) to 11.3 +/- 4.8 (p < 0.01). UPDRS tremor subscores were also significantly improved. Fourteen patients who enrolled in a multicenter, double-blind, placebo-controlled study underwent longterm tremor analysis in addition to the Columbia University Rating Scale (CURS). Tremor occurrence was improved in the budipine group (n = 7) from 24.7 +/- 15.5% to 14.8 +/- 14.5% (p < 0.05). Tremor intensity decreased from 9.1 +/- 2.5 (SNR) to 7.2 +/- 1.6. However, the latter result was statistically not significant, probably due to the small patient number. In the placebo-group (n = 7) there was no reduction of tremor occurrence or of tremor intensity. The CURS sum score was improved from 5.7 to 3.0 in the budipine group, whereas there was only a smaller improvement in the placebo group (from 7.1 to 5.5). These data suggest that budipine is an effective tremorlytic agent in PD, which may be used as an alternative to anticholinergics.