Bradykinesia akinesia inco-ordination test (BRAIN TEST): An objective computerised assessment of upper limb motor function

Abstract

Objectives - A simple and rapid computerised keyboard test, based on the alternating finger tapping test, has been developed to quantify upper limb motor function. The test generates several variables: (1) kinesia score: the number of keystrokes in 60 seconds; (2) akinesia time: cumulative time that keys are depressed; (3) dysmetria score: a weighted index calculated using the number of incorrectly hit keys corrected for speed; (4) incoordination score: a measure of rhythmicity which corresponds to the variance of the time interval between keystrokes. Methods - The BRAIN TEST® was assessed on 35 patients with idiopathic Parkinson's disease, 12 patients with cerebellar dysfunction, and 27 normal control subjects. Results - The mean kinesia scores of patients with Parkinson's disease or cerebellar dysfunction were significantly slower than normal controls (Parkinson's disease = 107 (SD 28) keys/min v cerebellar dysfunction = 86± (SD 28) v normal controls = 182 (SD 26), p < 0.001) and correlated with the UPDRS (r = -0.69, p < 0.001). The akinesia time is very insensitive and was only abnormal in patients with severe parkinsonism. The median dysmetria (cerebellar dysfunction = 13.8 v Parkinson's disease = 6.1 v normal controls = 4.2, p = 0.002) and inco-ordination scores (cerebellar dysfunction = 5.12 v Parkinson's disease = 0.84 v normal controls = 0.15, p = 0.002) were significantly higher in patients with cerebellar dysfunction, in whom the dysmetria score correlated with a cerebellar disease rating scale (r = 0.64, p = 0.02). Conclusion - The BRAIN TEST® provides a simple, rapid, and objective assessment of upper limb motor function. It assesses speed, accuracy, and rhythmicity of upper limb movements regardless of their physiological basis. The results of the test correlate well with clinical rating scales in Parkinson's disease and cerebellar dysfunction. The BRAIN test will be useful in clinical studies. It can be downloaded from the Internet (www.anaesthetist.com/software/brain.htm).