Response latency and accuracy in visual word recogniton

In a single visual word recognition experiment, the effects of (1) eccentricity of presentation, (2) word length, and (3) word frequency were investigated. The stimuli used were Dutch nouns in two frequency classes of about 15 and 150.10^-6; word length varied from 1 to 10; eccentricity varied from ?4 to +4 deg. The response quality and response latency of 11 subjects were measured. For the correct responses, recognition scores decreased and response latencies increased with eccentricity; both showed asymmetrical curves in the visual field. It is argued that word length proper affects neither the probability of correct responses nor latency. A clear word frequency effect was established. The eccentricity of presentation is considered as the determinant of the amount of available information, thus directly influencing accuracy and latency. The linear relationship between accuracy and latency is a major finding. A word recognition scheme is offered which incorporates (1) activation, (2) decision, and (3) speech. The time relations between incoming retinal information and response decision, leading to an extra 400 msec for incorrect as compared with correct responses, are discussed. Word recognition in reading is examined, together with the impact of the present experimental results on information flow in successive eye fixations, eye movement control, and eye-voice span.     

Global attributes in visual word recognition: Contour perception of three-letter strings

The expetiments reported here were designed to investigate the extent to which subjects perceive the contour of three-letter strings composed of permutations of the letters (k, x) or (d, o, p). The strings were presented for 100 ms at various retinal eccentricities. 13 subjects were required to report the entire letter string. Both average contour scores and individual letter scores decrease with eccentricity. Position in the string appears to be of paramount importance, letters farthest from the fovea showing the best performance. The extensions of the letters seem to be salient cues for perceptual analysis. Shortening of the extensions causes reduced accuracy in contour recognition.