The effects of articulatory suppression on reading ideographic and alphabetic numbers

The present experiments investigated the effects of articulatory suppression on reading numbers written alphabetically (one, two, etc.) or as Arabic numerals (1, 2, etc.). For alphabetic numbers, but not for numerals, a phonological representation can be generated and used for lexical access. If such phonological encoding occurs, and if it is harmed by irrelevant articulatory activity, then articulatory suppression should have a greater effect on the reading of alphabetic than on numeral representations of numbers. In contrast to a finding reported by Baron (1977), involving alphabetic and Roman numerals, in two experiments suppression was found to have essentially equivalent effects on the reading of both types of numbers. A third experiment explored a possible explanation for these discrepant findings. It is concluded that although alphabetic and numeral representations of numbers may be processed differently there is no evidence to support the idea that reading alphabetic numbers involves phonological encoding prior to lexical access.     

Book reviews

Gordon, I. E. (1989). Theories of visual perception. Chichester: John Wiley & Sons. Pp. 273. ISBN 0-471-92196-3. £12.50.

Shepp, B. E. & Ballasteros, S. (Eds.) (1989). Object perception: Structure and process. Hillsdale, NJ: Lawrence Erlbaum Associates. Pp. 431. ISBN 0-8058-0060-3 (hardback) £44.95; ISBN 0-8058-0333-5 (paperback) £22.95.

Frith, U. (1989). Autism: Explaining the enigma. Oxford: Basil Blackwell. Pp. 204. ISBN 0-631-15833-2. £25.00 (hardback); £8.95 (paperback).

Rollins, M. (1989). Mental imagery: On the limits of cognitive science. New Haven, CT: Yale University Press. Pp. 170. ISBN 0-30-04491-7. £18.00.

Lloyd, D. (1989). Simple minds. Cambridge, MA: The MIT Press. Pp. 266. ISBN 0-262-12140-9. £22.50.

Howard, D. & Franklin, S. (1988). Missing the meaning? A cognitive neuropsychological study of the processing of words by an aphasic patient. Cambridge, MA & London: MIT Press. Pp. xix + 171. ISBN 0-262-08178-4. £22.50.

Evans, J. St. B. T. (1989). Bias in human reasoning. Hove and London: Lawrence Erlbaum Associates Ltd. ISBN 0-86377-106-8. £14.95 (hardback) ISBN 0-86377-156-4. £8.95 (paperback).

Clark, A. (1989). Micorcognition: Philosophy, cognitive science, and parallel distributed processing. Cambridge, MA: MIT Press/Bradford Books. Pp. 226. ISBN 0-262-03148-5. £14.95.     

Vigilance ratios implicate biological rhythms

Vigilance research has been focused on differences, yet ratios might have intrinsic, numerical significance. Reanalysis of data from Watkins' 1963 psychophysical experiment and 49 vigilance reports showed that individual and group ratios, including errors or misses: detections, were related to roots (particularly of base 1/12 and multiples), powers, e-base ratios (EBR), and fractions. Examples are given from well-known experiments of remarkably exact relationships between conditions, time periods, etc. It is suggested that these phenomena are the product of biological rhythms. Theoretical implications are briefly discussed and the advantages of ratio analysis noted, as when this method proved that criterion beta changes, given as nonsignificant, formed part of an ordered set. In a real-world application, the frequency of lane-drifts in O'Hanlon and Kelly's 1977 report is shown to follow a mathematical pattern.