Some evidence for correlated separate activation in a simple letter-detection task

This study investigates the separate activation versus coactivation issue for redundant targets in a simple letter-detection paradigm with latency as the dependent variable. The results of a one-response visual-search task are reported. Since, on single-target trials, only the target was presented and no accompanying noise element, no “distraction decrement” caused by irrelevant noise elements (Grice et al., 1984) was to be expected. The data obtained showed a clear redundantsignal effect. Subsequent detailed analysis of the latency data using Miller’s (1982) procedure indicated that the results were consistent with a separate activation model and failed to provide convincing evidence in favor of coactivation models. A further analysis of the data indicated that, in the present study, the separate channels were negatively correlated for a range of fast RTs and positively correlated for intermediate and larger RTs. No evidence in favor of Grice et al.’s (1984) distraction-decrement hypothesis was found. The conclusions of this study are that (1) a separate activation model summarizes the essential features of information processing in this simple visual search task, and (2) no convincing evidence in favor of coactivation in visual search tasks has been reported in the literature up to now.     

On the relationship between stimulus intensity and duration of visible persistence

Stimulus intensity and duration of visible persistence have been found to vary directly in some studies but inversely in others. Hawkins and Shulman (1979) have proposed that this inconsistency can be resolved by separating the studies that employed a decrement-threshold measure of persistence (Type I measure) from those that measured the total duration of persistence (Type II measure). They suggested that Type I measures yield an inverse relationship, whereas Type II measures yield a direct relationship between intensity and persistence. Hawkins and Shulman's model is incomplete in ways that are easily remedied. However, the model is totally contradicted by the experimental evidence. A new resolution of the inconsistent results is proposed in terms of retinal afterimages.     

Working memory theory of hippocampal function needs qualification

To compare the predictive value of "cognitive map" and "working memory" theories of hippocampal function, the performance of rats with dorsal hippocampal lesions was compared to that of control rats in a series of experiments. In Experiment I, experimental rats learned a spatial alternation task with normal ease, but in Experiment II, they were significantly impaired on an elevated 8-arm radial maze. In Experiment III, the performance of the same experimental and control rats was compared on two versions of a 16-arm enclosed radial maze. In the first version, carpet inserts served as cues to mark eight unbaited arms and each of the remaining arms contained one food pellet. While both experimental and control rats successfully avoided the set of cued arms, experimental rats reentered uncued baited arms more frequently than did control rats. In the second version no intramaze cues were provided, but the spatial distribution of baited and unbaited arms remained the same as that used in the first version. In this uncued version, experimental rats both entered unbaited arms and reentered baited arms more frequently than did control rats, i.e., they were impaired in both "reference" and "working" memory. These findings are compatible with the hypothesis that hippocampal lesions result in an impaired capacity to form cognitive maps but they are not compatible with the working memory hypothesis. Furthermore, twelve separate evaluators classed experimental rats as using fewer mapping and more orientation strategies than control rats in the 8-arm maze.     

Studies of birth rates: social-psychological aspects

This is a general review of world literature and attitudes toward propaganda campaigns aimed at regulating population growth in the USSR. The goals, strategies, and psychological methods used in such campaigns are examined, and social attitudes toward population dynamics and family planning are explored. (SUMMARY IN ENG)     

Rapid error correction during human arm movements: evidence for central monitoring

Studies were made of rapid error correction movements in eight subjects performing a visually guided tracking task involving flexion-extension movements about the elbow. Subjects were required to minimize reaction times in this two-choice task. Errors in initial movement direction occurred in about 3% of the trials. Error correction times (time from initiation to reversal of movement in incorrect direction) ranged from 30-150 ms. The first sing of correction of the error movement was a suppression of the electromyographic (EMG) activity in the muscle producing the error movement. This suppression started as early as 20-40 ms after the initiation of the error-related EMG activity and as much as 50 ms before any overt sign of limb movement. The correction of the error movement was also accompanied by an increase in the drive to the muscle which moved the arm in the correct direction. This increased activity always occurred after the initiation of the error movement. it is concluded that the first step in the error correction, suppression of drive to the muscle producing the error movement, cannot be based on information from the moving limb. It is thus suggested that this earliest response to the error movement is based on central monitoring of the commands for movement.     

WESTERN PSYCHOLOGY IN THE PHILIPPINES: IMPACT AND RESPONSE*

The history of psychological science in the Philippines is considered as a case of cultural diffusion from the West through the English language and the institutions (educational and legal, business and industry, the media, government and the bureaucracy) which adopted the language. The development of academic and professional psychology and of psychology-related services has been phenomenal, particularly in the last decade. It has however, given rise to problems of (1) standards and validity in testing and research, and (2) applicability of concepts and methods in social psychology the roots of which are from another culture. Current trends and issues, as well the movement for indigenous Philippine social psychology, are briefly described.     

Attributions, beliefs about control, and adjustment to breast cancer

Attributions for cancer and beliefs about control over cancer were examined for their association with adjustment to breast cancer. Although 95% of the respondents made attributions for their cancer, no particular attribution (e.g., stress, diet) was associated with better adjustment. Analyses of attributions of responsibility for the cancer to the self, environment, another person, or chance yielded only a negative relation between adjustment and blaming another person. In contrast, both the belief that one could now control one's cancer and the belief that others (e.g. the physician) could now control the cancer were significantly associated with good adjustment. Of the different types of control, cognitive control was most strongly associated with adjustment, behavior control was less strongly associated with adjustment, and information control and retrospective control were unassociated with adjustment. The theoretical and practical implications of these results are discussed.