Combining speed and accuracy to assess error-free cognitive processes

Both the speed and accuracy of responding are important measures of performance. A well-known interpretive difficulty is that participants may differ in their strategy, trading speed for accuracy, with no change in underlying competence. Another difficulty arises when participants respond slowly and inaccurately (rather than quickly but inaccurately), e.g., due to a lapse of attention. We introduce an approach that combines response time and accuracy information and addresses both situations. The modeling framework assumes two latent competing processes. The first, the error-free process, always produces correct responses. The second, the guessing process, results in all observed errors and some of the correct responses (but does so via non-specific processes, e.g., guessing in compliance with instructions to respond on each trial). Inferential summaries of the speed of the error-free process provide a principled assessment of cognitive performance reducing the influences of both fast and slow guesses. Likelihood analysis is discussed for the basic model and extensions. The approach is applied to a data set on response times in a working memory test. The authors wish to thank Roger Ratcliff, Christopher Chabris, and three anonymous referees for their helpful comments, and Aureliu Lavric for providing the data analyzed in this paper.     

Hemispheric cognitive style: a comparison of three instruments

In this study, the author tested the reliability, concurrent validity, and predictive validity of three hemispheric cognitive style instruments: (a) the Preference Test (PT; R. Zenhausern, 1978), (b) the Polarity Questionnaire (PQ; B. E. Morton, 2002), and (c) the Wagner Preference Inventory II (WAPI II; R. F. Wagner & K. A. Wells, 1985). Participants were either teachers or teachers in training. The prediction criterion was in the area of teaching licensure. Scores on the PQ had extremely low reliability, and correlations with the PT and the WAPI II were not significantly different from zero. In addition, the PQ did not correlate with the licensure area. The author found that both the PT and the WAPI II had reasonable levels of reliability, and both instruments were able to explain a small percentage of the variance in the teaching licensure area. Using factor analysis of the PT, the author found a 7-factor structure, which suggests that hemispheric cognitive style might be decomposable into separate holist analytic and visual-verbal dimensions.     

Searching night and day: a dissociation of effects of circadian phase and time awake on visual selective attention and vigilance

How does sleepiness affect selective attention? We studied the effect of circadian phase and time awake on visual search. The generalized-cognitive-slowing hypothesis predicts that search rate will be slower, feature guidance less effective, and response time (RT) lengthened when observers are sleepy. Observers performed spatial-configuration (finding a 5 among 2s) and conjunction (finding red vertical among red horizontal and green vertical) search tasks during 38 hr of wakefulness under constant conditions. Adverse circadian phases and elapsed time awake did lead to increased RT (corrected for errors). However, contrary to the hypothesis, search rates (indexed by RT x Set Size slopes) were constant across the protocol. This was true for conjunction as well as for spatial-configuration search, indicating that feature guidance was also insensitive to sleepiness. The locus of sleepiness effects on search is probably downstream from the bottleneck of attentional selection. Observers did trade accuracy for speed when sleepy. This implicates decision-stage impairments.     

Synchronous and desynchronous changes during fear reduction.

The purpose of this experiment, carried out on 27 subjects with intense and circumscribed fears, was to test one main hypothesis and several subsidiary predictions. The prediction that a high-demand in vivo treatment condition produces desynchronous changes and a low-demand treatment condition synchronous changes, was supported by some inter-session findings but not by the intra-session findings. The clear linear relation between heart-rate and reported fear was confirmed, as was the rapid habituation of the heart-rate response to phobic stimulation.The fear-reactions and fear-reductions of psychiatric and non-psychiatric were indistinguishable. High heart-rate responders and low heart-rate responders showed similar patterns of improvement. The constrained laboratory ‘treatment’ procedure used in the experiment produced large and rapid reductions in fear.     

Are Christians Theologically Committed to a Rejection of the Principle of Alternative Possibilities?

Many philosophers think that free will requires alternative possibilities. Other philosophers deny this. There are plenty of philosophical arguments on both sides of this debate, but here I want to highlight various theological pressures that might push Christians into rejecting the principle of alternative possibilities. In this paper, I explore six cases that might push Christians in that direction: the case of divine foreknowledge, the case of prophecy, the case of the blessed in heaven, the case of Christ's human freedom, the case of Mary's fiat in light of her immaculate conception, and the case of prayers for the past. As I will argue, in each of these cases, given certain other standard theological commitments, it seems that Christians are pushed to admit that the agent in question does indeed act freely but also that he or she did not possess alternative possibilities at the moment of decision.     

Religious Requirement: The case for Roman Catholic schools in the 1940s and Muslim schools in the 1990s

This article sets out the four principles which underlay Catholic schooling in the 1940s. Similar principles were expressed by Muslim leaders in the 1990s. The origins of Catholic schools in the 19th century are described, as is the 1870 Act which led to a great increase in their number. Twentieth-century Catholic writers set out the rights and duties of parents and the obligation of the state to fund Catholic schools. The stance of the church in the 1940s is examined in detail. Some characteristics of Islam are then described. Religious observance brings conflict for children attending maintained schools. Parents may campaign for change in these schools, or opt for independent Islamic schools. The conclusions of the Swann Report (1985) regarding separate schooling are set out, followed by the change in government policy after 1997. In conclusion, the article asks whether we may expect an increase in Muslim voluntary aided schools parallel to the earlier increase of Catholic schools.     

Reflections on the process of psychotherapeutic change as applied to medical situations

This article takes the basic ideas on the process of changing implicit knowledge put forward in this special issue, and extends them beyond psychotherapy to include other therapeutic relationships that occur in medicine. One vignette, from an encounter between a medical student and a dying patient, illustrates how a “moment of meeting” changes the student as well as the patient. The second shows how therapeutic interventions for new mothers with their newborn infants involve “moments of meeting” that alter the mother's implicit knowledge of her baby and of herself as a mother. © 1998 Michigan Association for Infant Mental Health