ABSTRACT
Background: Neuropathic Tremor (NT) is a postural/kinetic tremor of the upper extremity, often encountered in patients with chronic neuropathies such as paraprotein-associated and hereditary neuropathies. Objectives: To describe the clinical and electrophysiological features of NT in a previously underrecognized setting- during recovery from Guillain-Barré Syndrome (GBS). Methods: Patients with a documented diagnosis of GBS in the past, presenting with tremor were identified from review of clinical records. Participants underwent structured, videotaped neurological examination, and electrophysiological analysis using tri-axial accelerometry-surface electromyography. Tremor severity was assessed using the Fahn-Tolosa-Marin Tremor Rating Scale. Results: We describe the clinical and electrophysiological features of 5 patients with GBS associated NT. Our cohort had a fine, fast, and slightly jerky postural tremor of frequency ranging from 8 to 10 Hz. Dystonic posturing and overflow movements were noted in 4/5 patients. Tremor appeared 3 months-5 years after the onset of GBS, when patients had regained near normal muscle strength and deep tendon jerks were well elicitable. Electrophysiological analysis of tremor strongly suggested the presence of a central oscillator in all patients. Conclusion: NT is not limited to chronic inflammatory or hereditary neuropathies and may occur in the recovery phase of GBS. The tremor is characterized by a high frequency, jerky postural tremor with dystonic posturing. Electrophysiological evaluation suggests the presence of a central oscillator, hypothetically the cerebellum driven by impaired sensorimotor feedback.
ABSTRACT
Background: Social cognition is the study of how people make sense of themselves and others. Impairment in several domains of social cognition is increasingly being recognized in Parkinson's disease (PD). Objectives: We aimed to study multiple domains of social cognition in Indian PD patients using a culturally appropriate, validated instrument. Methods: We recruited 52 individuals with PD and 31 healthy volunteers (HV) and used the Social Cognition Rating Tools in Indian Setting (SOCRATIS) tool to assess theory of mind (ToM), attributional biases and social cue perception. Quality of life (QoL) was assessed using the PDQOL scale. Results: Baseline characteristics were comparable between PD and HV. The mean (SD) FOT index (first order ToM index) was 0.86(0.18) in PD and 0.99(0.07) in HV [P < 0.001]. The PD group showed higher Externalizing Bias [EB, 4.42(3.91)], compared to HV [1.58(3.22), P = 0.001]. The mean (SD) Faux Pas Composite Index (FPCI ALT) was 0.69(0.09) in PD and 0.78(0.13) in HV [P < 0.001]. Social cognition indices were not associated with QoL in PD. Clinical parameters-age, gender, HAM-D, MOCA, education, levodopa equivalent daily dose of medication, number of PD drugs and trihexyphenidyl use did not predict social cognition. Conclusion: PD patients were less successful than age, gender matched controls in understanding social situations and other's thought processes and had higher tendency to attribute undesirable events to external causes. Deficits in social cognition did not impair the quality of life.
