Single-letter recognition as a function of exposure duration |
| |
Authors: | Claus Bundesen Lisbeth Harms |
| |
Institution: | (1) Center for Visual Cognition, Psychological Laboratory, University of Copenhagen, Njalsgade 90, DK-2300 Copenhagen S, Denmark Fax: +45 3532 8745; e-mail: bundesen@axp.psl.ku.dk, DK |
| |
Abstract: | The time course of visual letter recognition was investigated in a single-stimulus identification experiment. On each trial,
a randomly chosen stimulus letter was presented at 1 of 12 equiprobable positions that were equally spaced around the circumference
of an imaginary circle centered on fixation. Exposure duration was varied from 10 to 200 ms, and the letter was followed by
a pattern mask. The subject's task was to report the identity of the stimulus letter but refrain from guessing. For the briefest
exposures, correct reports never occurred. For longer exposures, the function relating the probability p of recognizing the letter to the duration t of the stimulus exposure was well approximated by an exponential distribution function: p(t) = 1 − exp−v·(t−t
0)], where v is the rate of processing and t
0 is the minimum effective exposure duration. The generality of this finding may be limited to cases in which stimuli are highly
discriminable and response criteria are conservative. Extensions to Poisson counter or random walk models are considered for
cases in which stimuli are confusable.
Received: 1 July 1997 / Accepted: 2 July 1998 |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|