Eight pigeons (Columba livia) were trained to discriminate between diagonal lines presented alone or embedded in a redundant L-shape right-angle form. The stimuli were white and were presented in an environment that was otherwise totally dark. Numerous experiments done with human observers have shown a strong superiority effect when the diagonal lines are embedded in redundant contexts. However, in Experiment 1 of the present study, the pigeons discriminated significantly better between the two diagonal lines when presented alone than when they were embedded in the right-angle context. In order to check on the possibility that these results were restricted to the semi-Ganzfeld condition of Experiment 1, a second experiment was done with black stimuli presented on a white background. Results of Experiment 2 also showed a strong distractor effect. The results ofthe present experiments confirmed the predictions of the Heinemann and Chase model of pattern recognition by pigeons.

The relationship between gender, age, and workers' attitudes toward sexual harassment as measured by the Sexual Harassment Attitudes Scale was examined. Participants were full-time workers employed at a local hardware-manufacturing company or a local utility company in New England. Results indicated that the women younger than 40 years old were significantly less tolerant of sexual harassment than older women were. In contrast, male workers' tolerance of sexual harassment decreased with age up until the age of 50 years, after which their tolerance level of sexual harassment increased significantly.

The effects of identical context on pattern recognition by pigeons for outline drawings of faces were investigated by training pigeons to identify (Experiment 1) and categorize (Experiment 2) these stimuli according to the orientation of the mouth-an upright U shape representing a smiling mouth or an inverted U shape representing a sad mouth. These target stimuli were presented alone (Pair 1), with three dots in a triangular orientation to represent a nose and eyes (Pair 2), and with the face pattern surrounded by an oval (Pair 3). In Experiment 1, the pigeons trained with Pair 1 were most accurate, those trained with Pair 2 were less so, and those trained with Pair 3 failed to acquire the discrimination within eighty 100-trial sessions. The same ordering was found in Experiment 2 for pigeons trained on the three pairs simultaneously. The authors suggest that a contrasting finding in humans, the face superiority effect, might be due to a gain in discriminability resulting from recognition of the pattern as a face. An exemplar model of information processing that excludes linguistic coding accounts for the present results.

In the experiments described in this paper we examined the effects of contextual stimuli on pigeons' recognition of visual patterns. Experiment 1 showed a context-superiority effect. Specifically, two target forms that were identical except for location in the visual field were not discriminated when presented alone, but the compounds formed when each of these targets was placed between a nearby pair of flanking stimuli were readily discriminated. The size of the contextsuperiority effect decreased with increasing target-flanker separation. In Experiments 2 and 3 the two targets differed in form rather than spatial location and were readily discriminated in the absence of flankers. Under these circumstances, adding an identical pair of flankers to each target resulted in a context-inferiority effect; that is, the two target-plus-flankers compounds were less readily discriminated than the targets alone. The size of the context-inferiority effect decreased with increasing target-flanker separation. The observed effects of context are predictable from the Heinemann-Chase (1990) model of pattern recognition.Numerous experiments have shown that discrimination between two forms-targets-is affected if each of the targets is accompanied by an identical, and therefore uninformative set of additional forms-contexts (Pomerantz, Sager, & Stoever, 1977;Weisstein & Harris, 1974). The effect of the contexts is evaluated by removing them from or adding them to the target forms under study. In accordance with recent usage (Enns & Prinzmetal, 1984), we shall refer to an improvement in discrimination between forms resulting from the addition of context elements as a context-superiority effect and impairment of discrimination as a result of the same operation as a contextinferiority effect.Investigators who have studied this phenomenon with human observers have found both context-superiority effects and context-inferiority effects (Enns & Prinzmetal, 1984;Pomerantz et al., 1977). Which of these effects will be produced by the presence of the common elements seems to depend on the specific configurations that areThe research reported here is part of a doctoral dissertation submitted by the first author to the City University of New York in 1991. It was supported by NIMH Grant ROI MH40712 to E.G.H. and S.C., and by PSC-CUNY Grant 669211 to E.G.H. We wish to thank the editor of this article, L. E. Krueger, as well as three anonymous reviewers, for many helpful comments and suggestions on an earlier version of the manuscript. Correspondence concerning this article should be addressed to F. J. Donis, Department of Psychology, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06050 (e-mail: donis@Ccsu.cstateu.edu).studied (Pomerantz et al., 1977), but a rule for predicting the direction of the effects solely on the basis of the stimulus forms has not been found.In most experiments the contexts themselves have been uninformative, in the sense that their forms were not correlated with the target forms and therefore...