Homograph coding and cerebral laterality

Abstract

Are homographs (e.g., can) more likely to be coded concretely (e.g., tin can) when presented to the right hemisphere and abstractly (e.g., I can go) when presented to the left hemisphere? To examine coding, homographs that had both concrete and abstract meanings were shown for 120 msec, after which subjects used each homograph in a phrase or sentence. The responses of male subjects were more concrete for words presented to the left hemisphere than for those presented to the right, but females showed no such laterality.We were interested in whether homographs presented to the right hemisphere would be coded differently from the same stimuli presented to the left hemisphere . For example, will "can" be concretely coded as "tin can" when sent to one hemisphere and abstractly coded as "I can go" when sent to the other?Rather than examine whether a single stimulus is coded differently by the two hemispheres, previous researchers have demonstrated that some types of stimuli (words) are processed more efficiently by the left hemisphere (Caplan, Holmes, & Marshall, 1974;Orbach, 1952), whereas other types of stimuli (such as faces and line slant) are processed more efficiently by the right hemisphere (Fontenot & Benton, 1972;Geffen, Bradshaw,& Wallace, 1971). There has been very little research on the direct effect of concreteness on laterality. Ellis and Shepherd (1974) reported that concrete words were recognized better than abstract words when presented to the left hemisphere . Other evidence that the right hemisphere is involved with "concrete" coding comes from Day (1977, p . 526) and Seamon and Gazzaniga (1973).In summary, various types of data show that the right hemisphere is specialized for concrete processing, whereas the left hemisphere is specialized for abstract processing. Accordingly, we expected to fmd codings to be more abstract when homographs were presented to the left hemisphere than when they were presented to the right hemisphere. This hypothesis was tested by presenting homographs in the left and right visual fields and then asking subjects to use each homograph in a phrase or sentence. MEmOD SubjectsThe subjects were 20 male and 20 female introductory psychology students whose participation partially fulfilled a course requirement. To qualify for participation, subjects had to Reprint requests should be sent to Keith A. Wollen, Department of Psychology, Washington State University, Pullman, Washington 99164. meet handedness and visual criteria. Subjects were required to respond "right-handed" to 8 or more of the 10 questions on the Hannay modification of the Neurosensory Center Handedness Questionnaire developed at the University of Iowa (Hannay & Malone, 1976). All visual tests were conducted at near point on a Bausch and Lomb Orthorater. Each subject had to have (1) 20/25 visual acuity or better, (2) .5 prism diopters or less of vertical phoria in either direction, and (3) no more than 3 prism diopters of esophoria or 6 of exophoria. The 40 subjects who met the criteria were randomly assigned t...