Gaussian counter models for visual identification of briefly presented, mutually confusable single stimuli in pure accuracy tasks

Publication date: Available online 28 April 2017 Source:Journal of Mathematical Psychology Author(s): Massimiliano Tamborrino, Susanne Ditlevsen, Bo Markussen, Søren Kyllingsbæk When identifying confusable visual stimuli, accumulation of information over time is an obvious strategy of the observer. However, the nature of the accumulation process is unresolved: for example it may be discrete or continuous in terms of the information encoded. Another unanswered question is whether or not stimulus sampling continues after the stimulus offset. In the present paper we propose various continuous Gaussian counter models of the time course of visual identification of briefly presented, mutually confusable single stimuli in a pure accuracy task. During stimulus analysis, tentative categorizations that stimulus i belongs to category j are made until a maximum time after the stimulus disappears. Two classes of models are proposed. First, the overt response is based on the categorization that had the highest value at the time the stimulus disappears (race models). Second, the overt response is based on the categorization that made the minimum first passage time through a constant boundary (first passage time models). Within this framework, multivariate Wiener and Ornstein–Uhlenbeck counter models are considered under different parameter regimes, assuming either that the stimulus sampling stops immediately or that it continues for some time after the stimulus offset. Each type o...

Source: Journal of Mathematical Psychology - April 29, 2017 Category: Psychiatry & Psychology Source Type: research