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This study statistically evaluated a set of commonly measured tremor parameters to determine their individual and combined ability to discriminate between essential tremor (ET) and Parkinsonian tremor (PT). Accelerometer and surface electromyographic (EMG) records of moderate to severe upper limb tremor in 20 patients with ET and 22 patients with PT were used to quantitatively compare tremor amplitude, frequency and pattern of muscle bursting in two resting and three non resting postures. The group statistics showed significant differences between ET and PT with respect to tremor frequency in all five postures, tremor amplitude at rest and muscle bursting patterns. Discriminant function analysis showed that no single parameter or combination of parameters was able to correctly classify all patients. Frequency was much more discriminating than amplitude or muscle bursting patterns in all limb postures. The best amplitude discrimination was obtained when the hand and forearm were both fully supported. Muscle bursting patterns were poorly discriminating and did not assist in correct classification of single patients. Group statistics confirmed a highly significant biological difference between the two tremor types. Optimal classification of single PT (86% correct) and ET (95% correct) patients was obtained using frequency and two selected amplitude parameters from the resting limb. Limb posture was an important variable in optimising the discriminative ability of tremor studies. The implications for routine tremor studies are summarised.

• Brain-stem auditory evoked responses (BAER) were recorded in a group of 83 patients with a diagnosis of clinically definite or probable multiple sclerosis to assess the relevance of recording contralateral responses simultaneously with ipsilateral responses and to correlate patients disability with the detection of abnormalities. The contralateral responses generally mirrored the ipsilateral responses, but in seven patients the responses differed, mainly involving the presence or absence of wave V. However, contralateral recordings did not contribute significantly to the sensitivity of lesion detection, and their main value was to aid in the recognition of waves when they were not clearly seen in the ipsilateral recordings. The BAER abnormality rates were found to be significantly correlated with disability, and it is suggested that this is an important variable to consider when undertaking or comparing results of BAER studies in patients with multiple sclerosis.

Nerve conduction studies were performed on 26 patients with polycythemia Vera, 11 of whom had sensory symptoms in the extremities and 3 of whom had clinical signs of peripheral neuropathy. There was significant impairment of sensory conduction in the ulnar and sural nerves and mild slowing of motor conduction in the lateral popliteal nerve. Sural nerve biopsies were performed on three patients. The pathological findings, including teased fiber studies, were consistent with mild chronic axonal degeneration. There is an association between polycythemia vera and peripheral neuropathy.

• A study of data on 30 patients with cervical spondylosis was carried out to determine whether short-latency somato-sensory-evoked responses (SEPs) to median, ulnar, radial, and peroneal nerve stimulation provided additional information to that obtained by electromyography (EMG), late responses, and peripheral conduction studies. Peripheral studies, EMG results and SEPs were within normal limits in ten patients with pain, but without objective neurological deficit. By contrast, of ten patients who had objective signs of root compression, conventional EMG results were normal in nine, but abnormalities of the SEPs from radial nerve stimulation were obtained in only five patients, and were normal from ulnar and median nerve stimulation. In ten patients with clinical features of myelopathy, seven had abnormal median SEPs and all had abnormal peroneal SEPs, whereas EMG results were abnormal in only five patients. It is suggested that SEPs and EMG are both of limited use in patients with only symptoms of root compression. In patients with signs of root compression, EMG is the most sensitive procedure; however, some additional information can be obtained from superficial radial SEPs. In patients with cervical myelopathy, SEP was the most useful procedure, especially when upper and lower limbs were studied.

• In 14 patients with tuberculosis treated with ethambutol hydrochloride, pattern-reversal visual evoked potentials (VEPs) were recorded to monocular, whole-field stimulation before the commencement of treatment and one month and three months subsequently. In six subjects, the VEPs showed changes in the latency and amplitude of the P100 component at the one- or three-month interval. In three cases, the VEP changes reversed after cessation of treatment. In five of the six cases, changes were not associated with a change in visual function, as measured by clinical neuro-ophthalmologic examination. Our findings confirm the usefulness of VEPs in the detection of subclinical optic nerve disease and suggest their use in routine monitoring of ocular function in patients treated with ethambutol.

Nineteen patients with spasmodic torticollis, unresponsive to standard therapy, were administered local injections of botulinum‐A toxin into the affected muscles. During an average follow‐up period of 11.5 months, a more than 25% improvement was noted in 14 of 19 patients. All those with purely focal dystonia and 9 of 10 patients with a disease history of less than three years benefited from treatment. Side effects were insignificant and transient. Botulinum toxin is a very effective and safe method of treatment for spasmodic torticollis.