title: Somatosensory discrimination of shape: prediction of success in normal volunteers and parkinsonian patients.
abstract: Tactile discrimination of macrogeometric objects in a two-alternative forced-choice procedure represents a complex task including somatosensory and higher-order cognitive processing. The objects for somatosensory discrimination were rectangular parallelepipeds that differed in oblongness only. They were presented in sequential pairs to 12 normal volunteers and 13 parkinsonian patients. Owing to the dichotomy of the task, we calculated estimates of the probability of a correct answer by a binomial approach. The probability of a correct answer could be calculated on the basis of a logistic model ensuring that the probability values lie in the interval [0, 1]. The relationship between the probability of a correct answer and the difference in oblongness of the objects could be described solely by one coefficient determined by logistic regression. This coefficient summarized the effectiveness of the simultaneous and consecutive operations inherent in the task and allowed characterization of performances in groups and individuals.
authors.affiliation: Klinik für Neurologie, Kantonsspital St. Gallen, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Weder
authors.forename: M
authors.initials: M
authors.lastname: Nienhusmeier
authors.forename: A
authors.initials: A
authors.lastname: Keel
authors.forename: K L
authors.initials: KL
authors.lastname: Leenders
authors.forename: H P
authors.initials: HP
authors.lastname: Ludin
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004193:Discrimination Learning / Q000502:physiology*; D005260:Female; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology* / Q000523:psychology; D011336:Probability; D012016:Reference Values; D013003:Somatosensory Cortex / Q000502:physiology*; D014110:Touch / Q000502:physiology*; D014741:Video Recording