Pitch discrimination in cerebellar patients: evidence for a sensory deficit.

In the last two decades, a growing body of research showing cerebellar involvement in an increasing number of nonmotor tasks and systems has prompted an expansion of speculations concerning the function of the cerebellum. Here, we tested the predictions of a hypothesis positing cerebellar involvement in sensory data acquisition. Specifically, we examined the effect of global cerebellar degeneration on primary auditory sensory function by means of a pitch discrimination task. The just noticeable difference in pitch between two tones was measured in 15 healthy controls and in 15 high functioning patients afflicted with varying degrees of global cerebellar degeneration caused by hereditary, idiopathic, paraneoplastic, or postinfectious pancerebellitis. Participants also performed an auditory detection task assessing sustained attention, a test of verbal auditory working memory, and an audiometric test. Patient pitch discrimination thresholds were on average five and a half times those of controls and were proportional to the degree of cerebellar ataxia assessed independently. Patients and controls showed normal hearing thresholds and similar performance in control tasks in sustained attention and verbal auditory working memory. These results suggest there is an effect of cerebellar degeneration on primary auditory function. The findings are consistent with other recent demonstrations of cerebellar-related sensory impairments, and with robust cerebellar auditorily evoked activity, confirmed by quantitative meta-analysis, across a range of functional neuroimaging studies dissociated from attention, motor, affective, and cognitive variables. The data are interpreted in the context of a sensory hypothesis of cerebellar function.

Improvement of balance in progressive degenerative cerebellar ataxias after Ayurvedic therapy: a preliminary report.

BACKGROUND: The treatment options for improving the balance in degenerative cerebellar ataxias are very few. Ayurvedic texts have described diverse treatment regimens for this disease. AIMS: To determine the change in balance indices, if any, by dynamic posturography (Biodex Balance System, USA) in progressive cerebellar ataxia following Ayurvedic treatment. MATERIALS AND METHODS: We performed a preliminary open labelled study on ten patients diagnosed with progressive cerebellar ataxia. The patients were treated over a period of one month. Treatment consisted of Shirobasti (therapeutic retention of medicament over the scalp) in male patients and Shirodhara (pouring of a steady stream of medicament on the forehead) in female patients with Dhanvantaram tailam (medicated oil) for 45 minutes daily, followed by Abhyanga (methodical massage) with Dhanvantaram tailam and Bhashpa sweda (steam bath), for 14 days. In addition, the treatment also consisted Abhyantara aushadha (oral medicines) of Maharasnadi kashayam 15ml thrice daily, Dhanvantaram capsules 101 two capsules thrice daily, and Ashwagandha tablet 500 mg one tablet thrice daily, for one month. The patients were assessed on the Biodex balance system before and after the treatment. Results were analyzed using paired samples 't' test. RESULTS: All patients tolerated the treatment well without any adverse events and reported subjective improvement in walking. There was a statistically significant improvement in the overall and anteroposterior balance indices of dynamic stability. CONCLUSIONS: Over the short period of the present study, Ayurvedic therapy was found to be safe and, showed improvement in the balance in patients with progressive degenerative cerebellar ataxia. Further randomized placebo-control double-blind studies are needed to validate the results.

Longitudinal study of bone and calcium metabolism and fracture incidence in spinocerebellar degeneration.

Little is known about bone and calcium metabolism and fracture incidence in spinocerebellar degeneration (SCD) despite frequent falls and immobilization. To address bone and calcium metabolism and fracture incidence in SCD, we conducted a 10-year prospective study in a cohort of adult patients with SCD. Bone mineral density (BMD) and serum levels of ionized calcium, parathyroid hormone, 25-hydroxyvitamin D, and pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP) were followed in 110 patients with SCD for 10 years. Age-matched healthy volunteers (n = 110) served as controls. At baseline, the SCD patients had a low BMD with high levels of serum ionized calcium and ICTP which correlated with the degree of immobilization (Barthel index). Over 10 years, serum 25-hydroxyvitamin D decreased to the osteomalacic level (<5 ng/ml), and calcium and ICTP further increased in accordance with a decreased Barthel index score. The BMD decreased by 15.2% in men and by 24.6% in women. The incidence of fractures in the patients was significantly higher as compared with the control group (men 8/49 vs. 1/42, p = 0.0428; women 16/49 vs. 2/48, p = 0.0026). Over 10 years, the BMD was significantly reduced in the SCD patients, particularly in women, which increased the risk of a fracture. Vitamin D deficiency due to sunlight deprivation, increased bone resorption due to immobilization, and frequent falls are probable causes of osteoporosis and fractures in these patients. Hypovitaminosis D and increased bone resorption may be corrected readily by the routine use of vitamin D supplements together with bisphosphonate.