Binocular summation in the perception of form at brief durations

Visual form identification at brief durations was studied under: (a) monocular presentation; (b) dichopic presentation where the same form was presented successively on noncorresponding areas; and (c) dichopic presentation where the same form was presented on corresponding areas simultaneously and successively. Form identification for noncorresponding area dichopic presentation was at the level to be expected from 2independent chances to perceive. Both simultaneous and successive dichopic presentation on corresponding areas gave identification accuracy significantly above the level predicted by the assumption of independence. However, the binocular summation was not complete. When the same amount of energy entering the visual system in a binocular presentation was given in a monocular stimulation, the latter condition gave significantly better identification.     

A survey of referral problems in 59 Ohio school districts

Feedback for the school psychologist is vital to construct and maintain remedial or preventative programs in the public schools. This study was undertaken to see if referral data would be useful as a source of such information.

Referral forms were solicited from school psychologists in 59 Ohio school districts and an analysis was made of their contents. The data obtained indicates that referral information can be used to provide school psychologists clues pertaining to referral procedures and the types of children and problems referred.

Specifically, this study indicates a greater need in the area of communication among pupil personnel workers. Further, it indicates that the psychologist in the school deals largely with problems of an academic nature thus offering a direction for in-service programming. Finally, the data reveals an interesting trend in the area of mental health which could possibly be an area of fruitful research.     

Improved standards for laboratory animals?

In February 1993, Judge Charles R. Richey of the United States District Court issued a summary judgment in the case of Animal Legal Defense Fund, et al. v. The Secretary of Agriculture, et al. The decision, which was in favor of the Animal Legal Defense Fund, requires the U.S. Department of Agriculture to withdraw its current regulations governing exercise for dogs and the psychological well-being of nonhuman primates used for biomedical research and to issue new regulations containing only minimum, measurable standards. Both plaintiffs and defendants contended that they were seeking the best interests of the laboratory animals. The issue at stake is whether animals are better protected if the government establishes limited minimal standards or is allowed to require institutions to provide additional standards, which will be judged on the basis of their effectiveness in maintaining healthy animals. The Court avoided this dispute, however, by placing primary emphasis on applying the Administrative Procedures Act and stating that it was merely interpreting the "plain meaning" of the Animal Welfare Act, as amended. In this article, arguments are presented for interpreting the law in a far more flexible way than Judge Richey did. The conclusion is also reached that there were no winners in the Animal Legal Defense Fund case and that the real losers are the laboratory animals.     

Properties of spatial representations: Data from sighted and blind subjects

Five questions concerning the properties of spatial representations are explored. (1) How accurately does a spatial representation correspond to the true scene? (2) If inaccurate, how does it differ? (3) Are representations of a familiar scene more accurate than those of an unfamiliar one? (4) Do representations of a scene currently in view differ from those retained in memory? (5) Do the representations of the blind have properties comparable to those-of the sighted? Seven sighted and 7 highly mobile blind subjects, all familiar with a room, and 6 sighted subjects unfamiliar with it, were asked to estimate the absolute distances between 10 salient objects in the room. The 14 familiar subjects made their estimates twice: while they were in the room, and while they were remote from it. Regression analyses showed that the estimates of all subjects had strong metric properties, being linearly related to true distance, with a true zero point; and multidimensional scaling showed that all subjects produced distance estimates that could be scaled in two dimensions to closely match the actual locations of the objects. Familiarity had no effect. The effect of location of testing was the same for both the sighted and the blind: all subjects displayed better spatial knowledge when tested in the room; and all subjects underestimated true distance substantially when tested out of the room. The results showed no qualitative differences as a function of blindness, at least for these highly skilled blind travelers.     

The use of partial temporal information in dating personal events

Memory & Cognition - The use of different types of partial temporal information is shown to affect dating accuracy and the distribution of errors in event dating. Several different types of...     

Book reviews

The Popularization of Medicine 1650–1850 Roy Porter (ed.), 1992 London, Routledge pp. x + 296, £50 (hardback) ISBN 0415 07217 4

Quantum Mechanics: An Empiricist View Bas Van Fraassen, 1991 Clarendon Press, Oxford pp. 558, £17.50 (paperback), ISBN 019 8239807