A biased random walk model for two choice reaction times

This paper generalizes Stone's (1960, Psychometrika 25, 251–260) random walk model of two choice response times (RTs) that is based on the sequential probability ratio test (SPRT) and that predicts equal correct and incorrect RTs to the same response. The generalized version allows a bias of the type found in signal detection theory to enter directly into the accumulation process so that ambivalent evidence may be seen as slightly favoring one alternative. The resulting biased SPRT model can predict any relation between correct and incorrect mean RTs. In particular, unlike the special symmetric case of Link and Heath's (1975, Psychometrika 40, 77–105) relative judgment theory (RJT), the biased SPRT model can predict that correct mean RTs are faster for one response but slower for the other. The biased SPRT model, the classical SPRT model, and the symmetric RJT model are all fit to the data of an RT deadline experiment reported by Green and Luce (1973, Attention and performance, New York: Academic Press) and it is shown that, of the three, the biased SPRT model provides the best account. Finally, a method for incorporating the same sort of bias into RJT models is sketched out.     

Implicit psychophysiology: Effects of common beliefs and idiosyncratic physiological responses symptom reporting

Every individual exhibits unique perceptual, behavioral, and physiological responses within and across a variety of settings. Despite the idiosyncratic nature of responses, we seek to establish theories that generalize across a large number of individuals. A strict idiographic method intensively examines the response patterns of a small number of individuals, whereas a nomothetic approach focuses on common responses across a large number of individuals. In the present investigation, we seek to learn how individuals perceive and report physical symptoms and sensations. We offer a methodology that capitalizes on the unique physiological responses of individuals but, at the same time, assumes that the underlying perceptual processes relevant to symptom reporting are comparable across individuals. Our approach, then, is both idiographic and nomothetic. As will be discussed, this integrative approach has the potential to be applied to a multitude of behaviors and processes that are of interest to social and personality psychologists.     

Locus of control and the aggression inhibiting effects of aggressive humor appreciation

Empirical investigation into the theoretical connection between humor appreciation and aggression has provided a continued series of equivocal results. This experiment examined the proposition that previous inconsistencies were due to the lack of concern for individual locus of control. Female subjects, differentiated as internals and externals, received either an aggression arousal induction procedure or a neutral nonarousal procedure. Subjects were presented three stimulus situations: neutral humor, aggressive humor, or nonhumorous material, and assessed for mood state. Locus of control was found to be a significant variable in the effectiveness of aggressive humor to reduce aggressive mood. Internals were able to reduce aggressive mood through appreciation of aggressive humor and demonstrated preference for this humor type. Importance of internals' cognitive style interacting with humor content was found significant in relationship between humor and aggressive reduction.     

Personality characteristics of the users of corporal punishment in the schools

The Rokeach Dogmatism Scale and the Eysenck Personality Questionnaire were correlated with educator-reported use of corporal punishment. Respondents were from a medium-size school system in Tennessee. Results indicated that closed-mindedness, as measured by the Rokeach scale, and Neuroticism, as measured by the Eysenck Scale, were highly correlated with reported use of corporal punishment. Of the remaining two dimensions of personality measured by the Eysenck questionnaire, Extraversion was found to be moderately correlated with reported use of corporal punishment while Psychoticism showed no significant relationship. A significant negative correlation was found between years of experience in teaching and use of corporal punishment. Frequency of physical punishment used on an educator when he/she was in grades K-12 was positively correlated with reported use of corporal punishment. Heavy users of corporal punishment tended to be relatively inexperienced, close-minded, neurotic, and impulsive as compared to their peers who did not use corporal punishment.     

The SOMPA: A brief examination of technical considerations,philosophical rationale,and implications for practice

The SOMPA is examined in terms of the multicultural model and Mercer's justification for multiple normal distributions within that model. The philosophical basis of the approach and the environments in which any assessment strategy must function are also examined. It is concluded that multiple normal distributions are not justified based on the variance accounted for in WISC-R scores by the Sociocultural Scales of the SOMPA. The pholosophical basis of the SOMPA, the sociology of knowledge, is not considered helpful or useful in the assessment process because of internal logic problems associated with the paradigm and because it creates an artificial separation of populations. Some of the components which influence education are examined in an effort to place the SOMPA in a realistic operational environment and to contrast the complexity of that environment with the oversimplified view offered by the SOMPA.     

Analgesic and opioid involvement in the shock-elicited activity and escape deficits produced by inescapable shock

Three experiments examined the involvement of analgesic processes and endogenous opioids in the production of the shuttlebox escape acquisition and unconditioned activity deficits which follow exposure to inescapable shock. Experiment 1 found that the opiate antagonist naltrexone administered before the inescapable shock session interfered with the shuttlebox escape acquisition deficit which would normally follow. Experiment 2 found naltrexone to completely prevent the unconditioned activity deficit. The final experiment revealed that dexamethasone, a synthetic glucocorticoid which abolishes the analgesia produced by inescapable shock, reversed the activity deficit. These results indicate that endogenous opioids may be involved in the production of both the escape acquisition and activity deficits. They also suggest that the analgesia produced by these opioids may participate in the mediation of the activity deficit, even though analgesia is not involved in producing the shuttlebox acquisition deficit.     

Discrimination and generalization by rats of temporal stimuli lasting for minutes

In three experiments, rats learned to respond differentially to reinforced and nonreinforced trials when the length of the intertrial interval (ITI) predicted the trial outcome (reinforcement or nonreinforcement). Rats in control groups, for whom the length of the ITI did not predict the outcome, did not show differential performance on nonreinforced and reinforced trials. Generalization gradients obtained following discrimination training were comparable to those obtained following discrimination training with other types of discriminative stimuli. That is, groups which had shown differential performance in discrimination training yielded generalization gradients with fastest speeds at the previously reinforced ITIs, slowest speeds at the previously nonreinforced ITIs, and intermediate speeds at ITIs of intermediate length. Control groups yielded flat gradients across all ITIs tested. These effects were shown for relative time discrimination (short time = reinforcement, long time = nonreinforcement, or the reverse) and also for an absolute time discrimination (long and short time = reinforcement, middle time = nonreinforcement or the reverse). This method was effective for time duration measured in minutes rather than seconds, as is more commonly the case.     

Concurrent schedules: Spatial separation of response alternatives

Four pigeons were exposed to independent concurrent variable-interval 20-second variable-interval 60-second schedules of reinforcement. A transparent partition was inserted midway between the two response keys. The length of the partition was systematically manipulated. Increasing partition length produced a decrease in changeover rate in Experiment 1. Over-matching was observed with a partition length of 20 centimeters. In Experiment 2 a four-second limited hold was added to the schedules. Increasing partition length produced a decrease in changeover rate that exceeded the decrease observed in Experiment 1. This manipulation produced nearly exclusive choice of the variable-interval 20-second component. The present results, together with results obtained in related research, suggest that deviation from matching is a function of procedural variables that determine the consequences of a changeover response.     

Accommodation fatigue and dark focus: The effects of accommodation-free visual work as assessed by two psychophysical methods

Past studies of accommodation fatigue have yielded inconsistent results, partly because they have not used direct measures of accommodation, and partly because they may have been based on a misleading conception of the nature of accommodation. The dual-innervation theory of accommodation suggests that the resting position of accommodation may be neuromuscular rather than just muscular, and that it lies not at optical infinity, as assumed by older conceptions, but at some intermediate position (dark focus). Among the predictions that may be deduced from this theory is that long-term visual work not requiring active accommodation will not induce fatigue. The present study involved continuous measurements of dark focus for 10 young adults over a 3-h period, using the laser optometer with two psychophysical procedures Ibracketing and staircase. Consistent with the prediction, no changes in dark focus were found, in spite of the demanding visual task. Furthermore, it was found that both psychophysical methods yielded essentially identical results. The practical and theoretical implications of these results are discussed, and recommendations are given regarding situations in which each of the psychophysical methods is likely to be most useful.