Science Education from a Social Constructivist Position: A Worldview

Studies in Philosophy and Education -     

Jaynes' chimeric faces: Another look into the mirror

In The Origin of Consciousness in the Breakdown of the Bicameral Mind, Jaynes (1976) presented a technique—involving the selection of the happier of two line-drawing chimeric faces—that is theorized to measure hemispheric laterality. Certain imperfections in the published stimuli have led some critics to question the task's validity, while others maintain that even the flawed stimuli are measuring some aspect of laterality. In this study, further data are presented to show that this task, despite its inherent biases, is still sensitive to differences in perception between left-handers and right-handers. The implications of this sensitivity are discussed.     

Language functioning after bilateral prefrontal leukotomy

Three groups of patients with orbital frontal lesions secondary to leukotomy were compared to psychiatric and normal control groups on a series of tasks involving language. The results indicated that chronic orbital frontal lesions, at least in the patients in this study, do not affect language as defined by the tasks used in the study. The frontal lobes, when implicated in language, appear to require dorsal-lateral or medial cortical involvement.     

Slowed lexical access in nonfluent aphasia: a case study.

A list priming paradigm (LPP) was used to examine the hypothesis that nonfluent aphasics are literally slowed down in automatic access to lexical information. In this paradigm, words are presented visually, and the subject's task is to make a lexical decision on each word as quickly as possible after its presentation. As soon as a lexical decision is made on one word, that word is removed and, after a predetermined interword interval, the next word is presented. In this way, a continuous "list" effect is obtained. Prior studies with both college-age and elderly subjects using the LPP have shown that, independently of age, on the LPP, priming obtains at interword delays of 500 to 800 msec, but not at either shorter or longer interword delays. In the study reported here, the LPP was used to examine delays at which priming obtained for LD, a nonfluent aphasic with a lesion primarily in the left frontal region. Examining interword delays ranging from 500 to 1800 msec, the subject showed priming only at a delay of 1500 msec, a considerably longer delay than that at which neurologically intact subjects have shown priming. Based on these results, it is argued that while automatic access is retained, that access is much slower in a nonfluent aphasic than in neurologically intact elderly subjects. These results are discussed in terms of how slowed lexical access might impact on discourse comprehension.