The effect of sleep deprivation on signal detection parameters

Twelve subjects performed a high signal rate vigilance task, once after a night's sleep, and once after a night without sleep. Raw scores were transformed into the signal detection parameters, d' and β. After sleep deprivation, detection performance was significantly impaired. This was reflected in a fall of d', whereas β was not significantly altered. Analysing the control data alone for comparison with other vigilance studies revealed a decrement in % signals detected and d', and an increase in β from the first to the second half of the test.     

Combination treatment of malignant brain tumors. Results of initial experiences

First experiences with the combined treatment of malignant gliomas (29 cases) are presented in connection with the results reported in literature. The cytostatic therapy has been carried out according to the modified Israel-Scheme of Heiss et al. Using the combined treatment (resection of tumor, radiotherapy and polychemotherapy) a prolongation of survival time to 55 till 80 weeks is noticeable. The patients observed in our study survived on an average 79,8 weeks (operation and chemotherapy) resp. 94,7 weeks (operation, radiotherapy and chemotherapy). Special problems of the cytostatic therapy of malignant brain tumors are considered, among others in relation to the blood-brain-barrier and the tumorcell-kinetics; a further optimation of therapy is necessary.     

Uncontrollability versus perceived failure as determinants of subsequent performance deficits

An experiment is reported that attempted to dissociate the effects of uncontrollability from those of failure in the standard learned helplessness induction procedure involving instrumental tasks. The task was administered to both university and high school students. The primary finding was a grade by controllability interaction, whereby uncontrollability had a larger effect for university students who became much more helpless. Further analysis revealed that while controllability or uncontrollability was the main determinant of university student performance, the performance of the high school students depended primarily upon success or failure. Perhaps we have previously generalized too widely from a restricted subject population.     

SOCIAL DIFFICULTY IN THREE CULTURES

An extended, piloted, version of the Bryant and Trower (1974) Social Situations Questionnaire was administered in Natal, South Africa, to nurses from three cultural groups: African, Indian and European, who were matched in terms of age, sex, education, occupation, and language competence. There was a significant difference between the three groups' self-reported social difficulty with the Europeans (Whites) expressing least social difficulty and the Africans (Blacks) most. Discriminant analysis revealed the items which showed most differences in the réponse between the three groups. The similarities and differences between the cultural groups in self-reported social difficulty are discussed within the context of their sociopolitical and cultural experience, and socialization. Implications for cross-cultural research in social skills are noted.     

Recognition memory for prose items in noise

Using a probe-recognition technique the signal detection theory parameters d' and Beta were estimated for three types of probe (common surnames, uncommon surnames and synonyms) for material contained in a prose passage. Subjects were presented with the prose passage either in the presence of noise (85dBA) or in quiet (60dBA). In two experiments the effects of noise on auditory and visual presentation of the passage were studied. In both cases the recognition test took place in quiet. Noise decreased values of Beta for rare names and increased Beta for common names in both auditory and visual versions of the task. Noise influenced d' values in the auditory version only, with d' increasing for common names in loud noise. The results support the view that noise influences performance by disturbing the pigeon-holing mechanism with the qualification that when material may not be recapitulated (as in the auditory presentation in the present study) greater attention may be allocated to easily recognizable material. The findings give little support to theories of noiseinduced deficits in performance based on the masking of inner speech.     

Attributions of stability and relevance of personality traits

This experiment tested a number of hypotheses derived from trait theory, attribution theory and interactional psychology. Forty subjects rated the stability and relevance of 60 pre-selected traits of three role-related people and themselves in four specific social situations. The traits were categorized beforehand in terms of their structural, motivational and content properties, and whether they were positive or negative. There was a significant difference in the perceived stability of positive and negative traits between liked and disliked people; positive traits being seen as significantly more stable in liked people and less stable in disliked people. However, subjects did not attribute significantly less stability to their own behavioural traits than to those of others in the same situations. It was also demonstrated that trait labels are seen to be differentially relevant for describing people in different social situations. The results are discussed in terms of the work on stability and cross-situational consistency in trait and attribution theory and person-situation research.     

The effect of lack of sleep on visual watch-keeping

Sixteen subjects performed a test of visual watch-keeping twice, at the same hour of the same day of successive weeks. The test lasted 40 min. On one of these occasions the test was done after normal sleep the previous night; signals were detected at a steady rate throughout. On the other occasion the subjects had no sleep the previous night; they passed the time in innocuous leisure activities. Here a similar level of performance was maintained for the first 20 min. of the test. After this the rate of signal detection declined steadily. In the final quarter of the test the rate was roughly one third that of the first quarter.

Signals missed were divided into three categories, (u) signals missed while watching the display, (b) signals missed while not watching, and, (c) signals missed while asleep. Lack of sleep produced increases in all three of these categories.

These results support previous suggestions that a test has to be prolonged before performance is affected by moderate loss of sleep; they also suggest that it is the simpler, or perhaps the more predictable, tests which are more affected.     

Classical conditioning and socialization—A biosocial interaction

While Eysenck (1977) has argued that socialization is in part determined by classical conditioning, there is little difinitive evidence to support this hypothesis. Close inspection of investigations carried out to date reveal most to contain conceptual or methodological flaws which invalidate their results as a strict test of Eysenck's theory. An attempt was made to circumvent these problems by testing Eysenck's undersocialization-poor conditionability prediction on a sample of 101 15-year-old male schoolchildren using self-report and teacher rating measures of socialization in conjuction with skin conductance measures of classical conditioning. This study also investigated the more specific hypothesis that biological predispositional factors are of particular relevance in determining antisocial conduct in the higher social classes (Mednick et al., 1977).Results of the first analysis provided no support for Eysenck's theory. In a second analysis an undersocialization-poor conditionability relationship was uncovered in the high-class children, a relationship which was reversed in the low classes. This result contradicts Eysenck's general prediction, is not readily interpretable by Mednick's analysis, but is explained by Eysenck's suggestion that in more criminogenic environments, superior conditionability facilities antisocial behaviour. These results suggest that the interaction between conditionability and social milieu needs to play a much more central role in the explanation of antisocial conduct than hitherto.     

A theory of causality: Causality=interaction (as defined by a suitable quantum field theory)

In this paper I put forward a suggestion for identifying causality in micro-systems with the specific quantum field theoretic interactions that occur in such systems. I first argue — along the lines of general transference theories — that such a physicalistic account is essential to an understanding of causation; I then proceed to sketch the concept of interaction as it occurs in quantum field theory and I do so from both a formal and an informal point of view. Finally, I present reasons for thinking that only a quantum field theoretic account can do the job — in particular I rely on a theorem by D. Currie and to the effect that interaction cannot be described in (a Hamiltonian formulation of) Classical Mechanics. Throughout the paper I attempt to suggest that the widespread scepticism about the ability of quantum theory to support a theory of causality is mistaken and rests on several misunderstandings.