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.     

Acquisition of phobias and anxiety response patterns in clinical patients

The ways in which phobic patients (N = 106; animal-, social- and claustrophobics) acquired their phobias were investigated in the present study. The results showed that a large majority (58%) of the patients attributed their phobias to conditioning experiences, while 17% recalled vicarious experiences, 10% instructions/information and 15% could not recall any specific onset circumstances. There was no clearcut relationship between the ways of acquisition and anxiety components (subjective, behavioral, physiological), nor did the conditioning and indirectly acquired phobias differ in severity. However, some interesting trends emerged in the data, showing that animal phobics who recalled conditioning experiences to a larger extent also responded physiologically. For patients with indirect onset experiences (for all three types of phobias) the reverse was true, i.e. they responded to a larger extent in a cognitive-subjective way, rather than with increased physiological arousal.     

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.     

The fate of ear asymmetries in short-term memory

Recognition memory for word lists presented to left or right ears was tested after filled retention intervals of 0-to 60-sec duration. Experiment 1 showed that the right-ear advantage (REA) for immediate recognition in dichotic listening does not occur after 10 sec delay. In Experiment 2, monaural presentation produced a nonsignificant REA which did not appear to be affected by delay. These data suggest that the REA for immediate report usually observed in the dichotic listening situation is a transient phenomenon which is based on phonetic encoding. The left hemisphere seems to be specialized for the initial reception of verbal information, but not for the storage or retention of such information over time.     

Short-term proactive inhibition in the pigeon

Proactive inhibition in the pigeon was studied using a delayed-color-matching-to-sample task, with and without presentation of stimuli prior to the sample. Interference theory predicts that, relative to control performance, the disruptive effects of a prior stimulus should increase over a retention interval, while decay theory predicts that such disruptive effects should decrease over time. Results supported decay theory when performance was at a low level and interference theory when performance was at a high level. With performance at an intermediate level, parallel functions were obtained, an outcome supporting neither theory. It was concluded that the results supporting interference and decay theories were artifactually produced by floor and ceilling effects, respectively, and it was suggested that the results of earlier experiments using the present paradigm may well have been influenced by similar artifacts. Inserting a nondisruptive stimulus between a prior disruptive stimulus and the sample virtually eliminated the disruptive effects of the prior stimulus when tested immediately, but not when tested after 1 sec. The results of the present experiments and related findings can best be explained by either a modified decay theory (Grant, D. S. Proactive interference in pigeon short-term memory. Journal of Experimental Psychology: Animal Behavior Processes 1975, 104, 207–220) or a modified temporal discrimination theory.