The time it takes to imagine1

Stanley and Furedy (1966), using the paired-comparisons technique, reported that under conditions where size constancy held, Emmert’s law failed as distance increased beyond 90 in. Experiment 1, designed to check this report with a shorter-duration induction flash, did not yield 90 in. as the point of failure. However, although complete size constancy for direct images was again obtained, the results did not unambiguously suggest strict proportionality between afterimage size and distance. To allow a less ambiguous assessment of proportionality, Experiment 2 used magnitude-estimation procedures. Distance estimates were completely veridical, but afterimage size varied only linearly, and not proportionally, with apparent distance. It was concluded the Boring (1940) was mistaken in his attempt to reduce size constancy and Emmert’s law to the same principle.     

Book reviews

Encyclopaedia of Linguistics, Information and Control. Edited by A. R. Meetham with the assistance of R. A. Hudson. Oxford: Pergamon Press. 1969. Pp. xiv + 718. 300s.

The Biological Basis of Personality. By H. J. Eysenck. Springfield: Thomas. 1968. Pp. xv + 399. $18.50.

Scientific Basis of Dvug Dependence. Biological Council Symposium. Edited by H. Steinberg. London: Churchill. 1969. Pp. 429. 100s.

Minnesota Symposia on Child Psychology, Vol. 2. Edited by John P. Hill. Minneapolis: University of Minnesota Press. 1969. Pp. viii + 172.

Memory and Attention: an introduction to human information processes. By Donald A. Norman. Chichester, Sussex: John Wiley. 1969. Pp. ix + 201. 84s. (cloth); 44s. (paper). Verbal Learning and Memory: selected readings. By Leo Postman and Geoffrey Keppel. Harmondsworth: Penguin Books. 1969. Pp. 501. 12s.

Handbuch der Kinderheilkunde. Edited by H. Opitz and F. Schmidt. Rand VIII/I: Neurologie-Psychologic-Psychiatrie. Redigiert von F. Schmidt und H. Asperger. Berlin: Springer Verlag. Pp. 1060. Price DM385, S96.25.

Digital Computing. By R. S. Lehman and D. E. Bailey. London: John Wiley & Sons Ltd. 1969. Pp. xxiv + 303. 79s.

Real-Time Computers. By W. R. Uttal. New York: Harper & Row. 1968. Pp. xiv + 338. 93s.     

Sense modality switching and serial leaming

This investigation examined the effect of sense modality switching ofinformation at various positions of a serial learning task. Different numbers of flashes of light and different numbers of “blips” ofa pure tone were used as signalsin a four-position serial learning task. The design of the study involved a switch in sense modality at each one of the four possible positions in the series. Thus, it was possible to determine if the transmission of information through one sense modality makes it progressively more difficult or more time consuming to switch to another source of information transmitted through another modality. The results generally supported the contention that, as information is received through a particular modality, there is a build-up of the disruption involved in switching sense modality.