Screening for Parkinson's disease with response time batteries: A pilot study

BACKGROUND: Although significant response time deficits (both reaction time and movement time) have been identified in numerous studies of patients with Parkinson's disease (PD), few attempts have been made to evaluate the use of these measures in screening for PD. METHODS: Receiver operator characteristic curves were used to identify cutoff scores for a unit-weighted composite of two choice response tasks in a sample of 40 patients and 40 healthy participants. These scores were then cross-validated in an independent sample of 20 patients and 20 healthy participants. RESULTS: The unit-weighted movement time composite demonstrated high sensitivity (90%) and specificity (90%) in the identification of PD. Movement time was also significantly correlated (r = 0.59, p < 0.025) with the motor score of the Unified Parkinson's Disease Rating Scale (UPDRS). CONCLUSIONS: Measures of chronometric speed, assessed without the use of biomechanically complex movements, have a potential role in screening for PD. Furthermore, the significant correlation between movement time and UPDRS motor score suggests that movement time may be useful in the quantification of PD severity

Reasons for Treatment Non-Response: A Controlled Study of Patients' Views in Pain Rehabilitation

Copyright © British Association for Behavioural and Cognitive Psychotherapies 2017. Background: Understanding successful and unsuccessful behavioural treatment for pain is essential. Aims: We carried out a retrospective survey of 130 people who had undergone pain rehabilitation based on acceptance and commitment therapy, aiming to identify factors associated with non-response. Method: The sample was selected using the reliable change index to define 'responders' and 'non-responders' to key outcome measures. We surveyed a range of treatment-related, systemic, practical and personal factors that may have affected their treatment, and then compared 'non-responders' with 'responders', controlling for factors that might not be causal or specific to non-response. Results: Logistic regression analysis showed two themes that distinguished the groups, 'people outside programme' and 'emotional state'. Conclusions: These data have clinical implications, as such factors can be addressed directly or incorporated into an assessment of treatment 'readiness'. This study introduced a novel methodology for the investigation of pain treatment response, which allowed a broad study of clinically relevant variables, but with greater rigour than conventional self-reports of 'helpful factors' in treatment

Reaction time deficits and Parkinson's Disease

Controversy surrounds the existence and nature of reaction time deficits in Parkinson's disease. Three areas of research are reviewed: the use of precues to speed movement (motor preprogramming), the effects of medication on reaction time, and simple reaction times. No evidence is found for a motor preprogramming deficit, and the presence of a parkinsonian reaction time deficit after medication withdrawal is found to be dependent upon experimental design and the withdrawal method used. Parkinson's disease is found to cause a consistent deficit in simple reaction time. A quantitative analysis of past studies reveals that a parkinsonian reaction time deficit is more likely to be present in tasks that controls can perform with a fast reaction time. This relationship between deficit and control group reaction time applies to choice, but not simple, reaction time tasks. Many studies compare patient and control choice reaction times across experimental conditions that cause control reaction time to vary. The authors of these studies should consider whether their results can be explained in terms of the simple relationship between patient reaction time deficit and control reaction time before drawing more complex conclusions from their data. (C) 1998 Elsevier Science Ltd. All rights reserved.</p