Intelligence and the processing of stimulus structure

It has been demonstrated in a number of experiments that the difficulty level of several performance type intelligence test tasks is determined directly by stimulus and task variables that vary the information to be processed. The variables are quantifiable. The implications of these findings for intelligence and the problems of an experimental approach to the measurement of intelligence are discussed.     

A note on the gross configurations of the human auditory cortex

Gross inspection of 30 human brains (60 hemispheres) from patients without hearing impairment revealed the following configurations of gyri: one on left and two on right (14 of 30); two on left and two on right (11 of 30); one on left and one on right (3 of 30); two on left and one on right (1 of 30); and two on left and three on right (1 of 30). The last group has since been extended to include all combinations other than the first four and the proportions of these combinations appear to persist in larger tallies. Thirteen of the 30 brains displayed double gyri on the left while 25 had double gyri on the right. Seventeen of the 30 brains possessed a single gyrus on the left and four specimens had a single gyrus on the right. In general, the left side has a tendency to fewer gyral markings. The average cortical surface area on the left is 1198 mm² compared to 1380 on the right.     

Deficits in temporal sequencing of verbal material: The effect of laterality of lesion

Temporal sequencing of verbal materials (digits, words, and geometric forms) presented in two sensory modalities (auditory and visual) to three groups of subjects (Broca's with left anterior lesions, patients with right hemisphere lesions, and normals) was examined. Each subject was asked to point to a set of stimuli in the same sequence as presented by the examiner. Results indicated that patients with left hemisphere lesions were more impaired on all tasks than the right hemisphere lesioned patients who, in turn, were impaired compared to normal controls. Response to auditory presentation was superior to response to visual presentation. Also, digits were the easiest for all groups, and words were easier than geometric forms. Of special interest was the finding which suggested that right hemisphere lesions are associated with impairment of verbal temporal sequencing under either auditory or visual presentation.     

Effect of mutual acquaintance on the construction of conversation

In a previous investigation, we demonstrated the role of questions as an instructional resource in the social construction of conversation by depriving conversationalists of their use. The resulting conversational structure, measured in terms of the ability of third parties to reconstruct the dialogues after they had been randomized, was impaired. The importance of culturally shared knowledge for the reconstruction (and by implication the construction) task was apparent in the superiority of British over Canadian subjects in reconstructing unconstrained British dialogues. The present study was concerned with the effects of privately shared knowledge on the construction of conversation. Conversational structure and the frequency of questions were greater in strangers' than in mutual acquaintances' unconstrained dialogues. Strangers' dialogues, but not those of mutual acquaintances, were disrupted under a ban on questions. The results were taken to indicate that strangers need to provide one another with continual instruction in how to proceed, whereas mutual acquaintances, in virtue of their privately shared social knowledge, can construct orderly dialogue with less moment-to-moment guidance.     

Influence of aging on recovery from aphasia in polyglots

We analyzed patterns of recovery, according to the rules of Pitres [1895, Revue de Medecine (Paris), 15, 873–899] and Ribot (1881, Les Maladies de la Memoire, Paris: Libraire Germer Baillere et Cie, pp. 146–147), in polyglot aphasics divided into subgroups by age. The rule of Ribot did not apply predictably for any age group. Pitres' rule clearly applied, but only for the nonelderly groups. Aging and its concomitant deterioration of recent memory seem to influence patterns of recovery from aphasia in polyglots.     

Disfluency characteristics of 2-, 4-, and 6- yr-old males

Fluency characteristics of 36 nonstuttering males aged 2, 4, and 6 yr are presented in terms of patterns of disfluency and relationships among disfluency variables. The most frequently occuring disfluency types at each age level were revision-incomplete phrase and interjections; the least noted type was part-word repetitions for 2- and 4-yr olds and disrhythmic phonations for 6-yr-olds. Patterns of disfluency appear to be similar at all age levels studied, except that the 2-yr-old pattern showed greater magnitudes in various disfluency types. A range exists in the relationships among individual disfluency types, from moderately strong relationships between, for example, revision-incomplete phrase and interjections to lack of linear relationships between, for example, interjections and phrase repetitions. A linguistic factor may be strong within certain disfluency types. e.g., revision-incomplete phrase, interjections, and word repetitions, whereas a motor factor may be operative in others, e.g., part-word repetitions and disrhythmic phonations.     

Korsakoff amnesic syndrome: The result of simultaneous deficits in several independent processes?

Alcoholic Korsakoff patients were presented six verbal list learning tasks (two denotatively and three connotatively organized, and one high-imagery word list). Twelve recall trials and three recognition probes were obtained per list. Results indicate that for Korsakoff patients, (1) recall varied with list organization, (2) recognition memory although poor was further disrupted by proactive inhibition only on denotatively categorized lists, and (3) conceptual deficits disrupted ability to appreciate simple dichotomies in denotatively categorized lists. It is hypothesized that the joint presence of deficts in specific conceptual and semantic processes in necessary although perhaps not sufficient to produce a Korsakoff amnesia.     

Cerebral lateralization of deaf and hearing individuals for linguistic comparison judgments.

A group of congenitally deaf adults and a group of hearing adults, both fluent in sign language, were tested to determine cerebral lateralization. In the most revealing task, subjects were given a series of trials in which they were fist presented with a videotaped sign and then with a word exposed tachistoscopically to the right visual field or left visual field, and were required to judge whether the word corresponded to the sign or not. The results suggested that the comparison processes involved in the decision were performed more efficiently by the left hemisphere for hearing subjects and by the right hemisphere for deaf subjects. However, the deaf subjects performed as well as the hearing subjects in the left hemisphere, suggesting that the deaf are not impeded by their auditory-speech handicap from developing the left hemisphere for at least some types of linguistic processing.     

A note on temporal relations between language and gestures

The initiation of the spontaneous gestures of Wernicke's aphasics was analyzed in relation to shifts in semantic content between the syntactic boundaries of main clauses and embedded clauses. Gestures proved more likely to arise at the initial boundaries of embedded clauses when these were semantically discontinuous with the main clause than when these were semantically related to the main clause. Spontaneous gestures may signal underlying shifts in semantic intention, thereby reflecting the difficulties encountered by Wernicke's aphasics in maintaining a coherent stream of thought across syntactic boundaries.