Mark S. Mayzner

A perspective on the recognition of other-race faces

The purpose of the present study is to provide a perspective on the recognition of other-race faces, i.e., black faces by white subjects. Past research has indicated that individuals have greater difficulty recognizing other-race faces than they do same-race faces. On the basis of previous findings, we chose to investigate the recognition of black faces by white subjects as a function of the quantity and quality of previous experience with blacks, racial attitudes, field dependence/independence, and recognition training. Forty-two white subjects participated in pre-, post-, and delayed recognition tests. Subject data were also collected to explore individual differences in recognition performance. Using multiple regression techniques, it was found that field dependence/independence accounted for the largest proportion of variance in recognition performances; a feature-discrimination training task and past experience with blacks were also found to significantly relate to recognition performance. The applied aspects of these results are discussed.

Application of geometric models to letter recognition: Distance and density

This article reviews studies in which a single letter is visually presented under adverse conditions and the subjects task is to identify the letter. The typical results for such studies are (a) certain pairs of letters are more often confused than other pairs of letters; (b) certain letters are more easily recognized than others; and (c) confusion errors for a letter pair are often asymmetric, the number of errors differing depending on which letter of the pair is presented as the stimulus. A geometric model incorporating the properties of distance and spatial density (after Krumhansl) is presented to account for these results. The present application of the distance-density model assumes that each letter is constructed in a typical 5 X 7 dot matrix. Each letter is represented in 35-dimensional space based on its constituent dots. A central idea behind the model, embodied in the property of spatial density, is that an explanation of typical results must take into account the relationship of the entire stimulus set to both the presented letter and the responded letter. Specifically, according to the model, (a) pairs of letters that are close in geometric space are more often confused than pairs of letters that are distant; (b) letters that are in less spatially dense regions are more easily recognized than letters that are in more spatially dense regions; and (c) asymmetric confusion errors result when one member of a letter pair is in a denser region than the other member of the letter pair. The distance-density model is applied to published and unpublished results of the authors as well as published results from two other laboratories. Alternative explanations of the three typical letter recognition results are also considered. The most successful alternative explanations are (a) confusions are an increasing function of the number of dots that two letters share; (b) letters constructed from fewer dots are easier to recognize; and (c) asymmetries arise when one member of a letter pair is more easily recognized, since that letter then has fewer confusion errors to give to the other letter of the pair. The model is discussed in terms of the distinction between template matching and feature analysis. An alternative classification of letter recognition models is proposed based on the global versus local qualities of features and the spatial information associated with each feature. The model is extended to explain reaction time study results. It is suggested that the distance-density model can be used to create optimal letter fonts by minimizing interletter confusions and maximizing letter recognizability.

The letter-frequency effect and the generality of familiarity effects on perception

A widely accepted perceptual principle is that familiar patterns are easier to recognize than are less familiar patterns. Previous letter-recognition studies are examined to determine whethermore frequent letters in English are easier to recognize than less frequent letters (the letterfrequency effect). Most studies required subjects to identify single letters, while some measured reaction time to compare two letters or name or classify a letter. The results, based on over 800, 000 observations from 58 studies that span nearly 100 years, showed that: (1) there is no letter-frequency effect in recognition studies in which subjects simply report letters, and (2) there is a letter-frequency effect in reaction time studies. The presence of la letter-frequency effect for reaction time studies is interpreted as demonstrating an effect of familiarity on a comparison stage and perhaps a response stage, but not on input coding. The absence of a letter-frequency effect for single-letter recognition studies is interpreted as limiting the generality of the effect of familiarity on perception and as limiting the generality of models that correctly predict frequency effects for words. Alternative explanations for the absence of a letter-frequency effect are discussed.

A reassessment of target-mask interaction in visual backward masking

Most theories of visual masking concentrate on the effects of a mask on a target. The present study departs from this position and investigates the manner in which a suppressed target alters the perception of a mask. A visual backward masking paradigm was employed, except that subjects were to identify characteristics of the mask rather than the target. A 5 by 5 square matrix of points, composed of either horizontal or vertical vectors, served as the mask. The mask was observed in both the presence and absence of preceding target stimuli. If observed in the absence of a target, the mask points appeared static and simultaneous. If preceded by a target, the mask points appeared to move in accordance with the orientation of the target. This finding implies a mutual sort of target-mask interaction. Several theoretical implications are discussed.

Variability in word-recognition performance

The present study, employing a backward visual masking paradigm and a computer-based CRT display system, examines the word-recognition performance for 220 four-, five-, and six-letter words, with a sample of 50 subjects. Results, as found previously, continue to demonstrate very large individual variabilities in such information processing tasks.

On an illusion of visual temporal order

Earlier work of Sekuler and his associates on visual temporal order is replicated, with a similar experimental paradigm. Our results, as those of Sekuler, suggest an internal mechanism that scans visual inputs in a left-to-right order, but also suggest that such internal scans may also proceed in top-to-bottom or bottom-to-top orders.

Foveal task effects on same-different judgments in the visual periphery

An attempt was made to examine the extent to which the presence of a foveal stimulus affects same-different judgments regarding the horizontal-vertical orientation of two lines located in peripheral vision. The results of the study indicated that accuracy in reporting peripheral visual stimuli is determined not only by the nature of those stimuli, but also by whether other stimuli are presented foveally. The simultaneous presence of another stimulus in foveal vision reduces accuracy in reporting peripheral stimuli, independent of instructions to ignore, detect, or identify the foveal stimulus.

Angular estimation: An exploratory study

Employing a backward visual masking paradigm, three exploratory studies were carried out to examine the effects of angle size and ISI on angle recognition processing. The results suggest that increasing size probably improves angle recognition performance, but clearly, much additional work remains.

Robustness of the dynamic visual movement effect

The present study examines further the effects of certain selected spatiotemporal parameters on dynamic visual movement. The results suggest that the subjectively perceived number of inputs is highly sensitive to the spatiotemporal ordering of the input array.

Detection and recognition of alphabetic characters: Simultaneous and contiguous

The present experiment was designed to examine the temporal ordering of detection performance and recognition performance in the perception of alphabetic characters, employing a visual backward-masking by noise paradigm. The results suggest that the encoding processes that lead to a correct “detection” response are completed earlier than the encoding processes that lead to a correct “recognition” response.