Letter Identification in Words and Non-Words, with Variation in Visual Angle and Delay of Position Cue

Perception ◽  
1982 ◽  
Vol 11 (3) ◽  
pp. 305-317 ◽  
Author(s):  
Robert T Solman

Two experiments are described in which subjects were required to report the name of a single position-cued ‘critical’ letter in a tachistoscopically displayed string of four letters. The stimulus characters were arranged to form three types of letter strings: (i) strings in which the letters did not form words; (ii) words in which contextual constraint of the critical letters was minimised; and (iii) words in which contextual constraint of the critical letters was maximised. The serial position of the letter to be identified in each string was cued at delays of −500, −100, and +500 ms, in experiment 1 and at delays of −510 and +510 ms in experiment 2, and in both experiments one group of subjects responded to letter strings which subtended a horizontal visual angle of 3·95 deg, while a second group responded to strings which subtended 1·02 deg. Correct identifications of critical letters showed that the presentation of words resulted in superior performance. This ‘word superiority effect’ is consistent with earlier findings implying that it has a perceptual locus. For the stimuli which subtended the large visual angle the word advantage was detrimentally affected only when the position of the critical letter to be identified was cued either 500 or 510 ms prior to the display of the letter string.

2006 ◽  
Vol 1098 (1) ◽  
pp. 153-160 ◽  
Author(s):  
Clara D. Martin ◽  
Tatjana Nazir ◽  
Guillaume Thierry ◽  
Yves Paulignan ◽  
Jean-François Démonet

1978 ◽  
Vol 6 (1) ◽  
pp. 3-8 ◽  
Author(s):  
Dean G. Purcell ◽  
Keith E. Stanovich ◽  
Amos Spector

1982 ◽  
Vol 34 (1) ◽  
pp. 117-134 ◽  
Author(s):  
Dean G. Purcell ◽  
Keith E. Stanovich

A word superiority effect was obtained using a fixed stimulus set, positional certainty of the critical letter, mixed trial type, and instructions to fixate the critical letter. Control experiments established that this effect was not due to lateral masking. Further experiments extended the finding of a fixed-set word superiority effect to other stimulus sets, and to lowercase and mixed-case stimuli. The mixed-case word superiority effect is inconsistent with supraletter feature models of word recognition and, instead, lends support to hierarchical codes models. It was demonstrated that an unusually wide spacing of letters can disrupt the formation of word-level codes, and that wide visual angles are not necessarily disruptive as long as normal spacing is maintained.


Perception ◽  
1987 ◽  
Vol 16 (5) ◽  
pp. 655-669 ◽  
Author(s):  
Robert T Solman

In two experiments subjects were asked to report the identity of a position-cued critical letter in an array of four letters. Four types of arrays were used: (i) unpronounceable nonwords; (ii) pronounceable nonwords (‘pseudowords’); (iii) words in which the critical letter was minimally constrained by the context letters; and (iv) words in which the critical letter was maximally constrained by the context letters. All four-letter stimuli were presented in two parts. A leading array in which the information from two quadrants of a vertical by horizontal division of each letter was presented, and, after intervals of 0, 20, 40, 80, 100, 120, 160, 320, and 480 ms and infinity (ie, no trailing array), a trailing array of the complementary letter parts. In experiment 1 a single group of eight subjects responded to the one hundred and sixty combinations of the four types of letter strings, the four serial positions, and the ten stimulus onset asynchrony values. In experiment 2 the stimulus onset asynchrony values were varied among subjects, with twelve subjects responding at each value. The results from these two studies were generally similar. Performance in the word conditions was consistently superior to performance in the nonword conditions, and the magnitude of this difference (ie, the word-superiority effect) increased with increasing stimulus onset asynchrony up to 120 ms, and then gradually declined. The fact that the magnitude of the word-superiority effect initially increased with the separation of leading and trailing arrays was interpreted as support for Johnston's suggestion that letters in words are represented during visual encoding both in the form of individual letter percepts and in a decay-resistant word percept, as opposed to letters in nonwords, which are represented only as decay-susceptible letter percepts. The experimental findings are discussed in relation to the ‘interactive activation’ model of word perception.


1973 ◽  
Vol 4 (2) ◽  
pp. 207-228 ◽  
Author(s):  
Jonathan Baron ◽  
Ian Thurston

1990 ◽  
Vol 103 (3) ◽  
pp. 299 ◽  
Author(s):  
David H. Peterzell ◽  
Grant P. Sinclair ◽  
Alice F. Healy ◽  
Lyle E. Bourne

Sign in / Sign up

Export Citation Format

Share Document