Some aspects of language comprehension in anterior aphasia

The competency of language comprehension was evaluated in three groups: anterior aphasics, posterior aphasics, and normal control subjects. Test material was divided into two sentence groups (Fill in the Blank and True/False) emphasizing either (1) semantic, “real world,” identity words or (2) syntactic, relational words, and one paragraph interpretation task. Matching auditory and visual (written) presentations were given. The control subjects performed almost flawlessly but many errors were made by each aphasia group. Qualitative study revealed a marked difference in the comprehension problem of the two groups. The anterior aphasic group performed well on semantically weighted sentences but made errors on syntactically weighted material, regardless of mode of presentation. In contrast, the posterior aphasics made almost the same number of errors on both types of material, regardless of mode of presentation. These findings support the concept of defective language comprehension in anterior aphasia and further suggest that the defect centers on the syntactical structures which are also poorly handled in expressive output.     

Extraversion and the orienting reaction habituation rate to visual stimuli

Eysenck's (1967) proposal that introversion is characterized by increased levels of activity in the cortico-reticular loop was treated in a series of experiments which compared high, middle, and low extraversion groups on the basis of OR habituation rate to visual stimulation. Generally, introverts were observed to have longer OR habituation rates to chromatic and word stimulation than extraverts as evidenced by cardiac, electrodermal, and vasomotor indices of habituation rate, a result which endorses Eysenck's hypothesis. Results are also discussed from the standpoint of individual differences in autonomic response.     

Investigative versus realistic Holland types and adjustment in theoretical engineering majors

This study tested the sensitivity of J. L. Holland's (Making vocational choices: A theory of careers, Englewood Cliffs, N.J.: Prentice-Hall, 1973) congruence method for predicting differential outcomes in the case of subtle person-environment congruence differences. This question is relevant to engineering programs, where students with adjacent Holland orientations of Investigative (I) and Realistic (R) aspire to complete theoretically oriented engineering majors, such as electrical and mechanical engineering. It was hypothesized that high congruence (e.g., I-type student in I-type engineering major) compared to moderately high congruence (e.g., R-type in I-type major) would result in more positive educational outcomes. A preliminary analysis verified that subgroups of I- and R-type students possessed similar scores on measures of general and math aptitude. Results on both outcome measures favored the high student-curriculum congruence hypothesis. I- compared to R-type subjects demonstrated greater persistence in their initial engineering major over a 2-year period and attained higher grades. Persistence findings replicated across two separate classes of entering students, but academic performance differences were not as consistent.     

The effects of symmetry and contour on recognition memory in children

Children in prekindergarten, kindergarten, and second grade were tested on a delayed match-to-sample task using abstract visual patterns. The patterns varied both in type of visual organization (unstructured, diagonally symmetrical, vertically symmetrical, and horizontally symmetrical) and in amount of contour. Following the initial memory task, we attempted to train half of the children at each grade by directing their attention to axes of symmetry; the other half of the children received a control task. Subsequently, the subjects were given a second delayed match-to-sample test. On both pre- and post-training trials, structure influenced performance, especially in the two younger groups. Vertical and horizontal symmetry generally facilitated performance in the prekindergarteners, while all three types of symmetry facilitated performance in the kindergarteners. In addition, children generally responded more accurately to patterns with lower levels of contour. They also made more like-contour than unlike-contour confusions, indicating that quantitative aspects of patterns were encoded. Group differences suggested that both processing capacity and memory increase during the age range studied. Finally, there was no indication that training improved performance at any age.     

Modality-specific interference with overt mediation by pigeons in a delayed discrimination task

Pigeons were trained on a delayed discrimination task in which they were rewarded for pecking a white terminal stimulus (TS) presented 5 sec after a green initial stimulus (IS) and for not pecking the white TS when it followed a red IS. Each bird bridged the memory interval (MI) with overt mediational behaviors. Nevertheless, sustained retroactive interference (RI) effects were produced by houselight illumination (Experiments 1 and 3), and mild shock pulses (Experiment 5) but not white noise (Experiment 2) presented during the MI. Although the magnitude of the light-induced RI effect was proportional to the duration of houselight illumination (Experiment 4), the beginning-end effect described by W. A. Roberts and D. S. Grant (Journal of Experimental Psychology: Animal Behavior Processes, 1978, 4, 219–236) was not observed. These results not only attest to the between-task robustness of both light-induced RI and modality-specific effects with pigeons, but also support the hypothesis that RI effects result from the disruption of mediational activities possibly analogous to rehearsal. The results further demonstrate that an event interpolated within the MI need not be unexpected or novel to produce RI. Furthermore, the interpolated event can produce modality-specific RI effects even though it effects a different sense than do the IS and TS.     

Developmental changes in face processing: results from multidimensional scaling

Multidimensional scaling procedures were used to investigate developmental changes in the ability to process previously unfamiliar faces. Eighty male subjects, aged 7, 9, 12, or adult, rated the similarity of pairs of faces. The faces were presented to subjects in either the upright or the inverted orientation. Multidimensional scaling analyses suggest that subjects of all ages use similar information in judging the similarity of faces. However, for upright faces, individual subjects under age 10 seem to use fewer features at a time. The results argue against a qualitative shift in face processing at age 10, and suggest that the improvement in face recognition ability noted at this age is due at least in part to an increased ability to consider more features simultaneously.