Comparison of behavioral and cognitive-behavioral one-session exposure treatments for small animal phobias

This study evaluated the efficacy of behavioral and cognitive-behavioral one-session exposure treatment procedures with and without programmed generalization for participants with small animal phobias. Forty participants were randomly assigned to the treatment and generalization conditions. Both treatments produced significant improvements from pre-test to post-test and these results were maintained for 1 year. The treatment effect sizes ranged from large to very large across behavioral, self-report, and subjectively rated measures. Participants in the behavioral treatment condition reported that the treatment was significantly more intrusive than participants in the cognitive-behavioral treatment group. The programmed generalization condition did not produce additional measured benefit. The results are discussed in terms of the overall effectiveness of one-session exposure treatment components for small animal phobias.     

College students, tattoos, and sexual activity

This research examined the association of having a tattoo and engaging in premarital sexual intercourse. Data gathered from a convenience sample of 450 college students indicated that tattooed respondents were substantively and significantly more likely to be sexually active than nontattooed college students. Tattooed men became sexually active at a significantly earlier age than nontattooed men but no such difference was found between tattooed and nontattooed college women.     

Involuntary retrieval in alphabet-arithmetic tasks: Task-mixing and task-switching costs

This study explores the effects of memory retrieval in task switching. To this end, item-specific stimulus-to-task mappings were manipulated in two alphabet-arithmetic experiments. Letter-stimuli were presented and the responses were verbal letter names. The task was either to name the next letter in the alphabet, (e.g., C D, task plus), or to name the preceding letter (e.g., C B, task minus). The mapping of individual stimuli to the two tasks (and thus to responses) was either consistent (CM) or varied (VM). In Experiment 1, performance was worse for VM items relative to CM items, indicating item-specific task-mapping effects. These task-mapping effects also contributed to mixing costs (i.e., worse performance in mixed-task blocks than in pure-task blocks) but not to switch costs (worse performance in task-switch trials than in repeat trials within mixed blocks). Experiment 2 manipulated pure and mixed tasks between-participants, and the data again showed differential effects of the task-mapping manipulation on mixing costs and switch costs. This suggests that, in these memory-dependent, alphabet-arithmetic tasks, interference due to involuntary task (and/or response) retrieval primarily increases general multi-task effects, such as maintaining activation of the current task.     

Effects of response selection on the task repetition benefit in task switching

A task switch typically leads to worse performance than a repetition does. This shift cost can be reduced with sufficient task preparation time, but a residual cost usually remains. We propose that a large part of this residual cost is caused by an activation bias produced by response selection processes in the preceding trial. In our experiments, we manipulated response selection requirements using a go/no-go methodology. The residual shift cost disappeared after no-go trials, suggesting that response selection is crucial to establish an activation bias for the current category-response rules and that this bias persists into the next trial. A comparison with a go-only group confirmed this analysis by revealing no differences in preparatory strategy due to the inclusion of no-go trials. In addition, no-go trials had no significant effects on subsequent trials in a single-task experiment, suggesting that no-go trials are not coded as a task different from go trials and that there is no inhibition of the prepared task in a no-go trial. We thus conclude that a persisting activation bias of response rules plays a major role in task switching.     

Linking inhibition to activation in the control of task sequences

Inhibition of abandoned tasks in task switching can be inferred when a worse performance is found withn− 2 task repetitions (ABA sequences) than with nonrepetitions (CBA sequences). Recent evidence has shown that this inhibition effect decreases with long intertrial intervals (i.e., response-cue intervals, RCIs). Two alternatives have been proposed to account for this decrease. One alternative attributes the observed decrease to the decay of inhibition itself. The other alternative proposes that decay of the activation of competing tasks reduces the interference and leads to less inhibition. To decide between these alternatives, we manipulated RCI trialwise. The results favor the decay-of-activation account as an explanation for the decreased inhibition effect. This links the amount of inhibition to the activation level of the competing tasks, whereas evidence for the decay of inhibition remains weak.     

Is perception discrete or continuous?

How does conscious perception evolve following stimulus presentation? The idea that perception relies on discrete processing epochs has been often considered, but never widely accepted. The alternative, a continuous translation of the external world into explicit perception, although more intuitive and subjectively appealing, cannot satisfactorily account for a large body of psychophysical data. Cortical and thalamocortical oscillations in different frequency bands could provide a neuronal basis for such discrete processes, but are rarely analyzed in this context. This article reconciles the unduly abandoned topic of discrete perception with current views and advances in neuroscience.     

They Might as Well be in Bolivia: Race,Ethnicity and the Problem of Solid Organ Donation

Theoretical Medicine and Bioethics -     

Distanced Perspectives: Aids,Anencephaly, and Ahp

US court decisions guaranteeing life-sustaining care to anencephalic infants have been viewed with disfavor, and sometimes disbelief, by some ethicists who do not believe in the necessity of life-sustaining support for those without cognitive abilities or an independently sustainable future. The distance between these two views – one legal and inclusive, the other medical and specific – seems unbridgeable. This paper reports on a program using multicriterion decision making to define and describe persons in a way which both acknowledges the differences perceived by many as well as those commonalities insisted on in U.S. court decisions. It does this through application of the Analytic Hierarchy Process to a hierarchy of humanness criteria, and secondarily through reference to that concept's subset, personhood.     

Recall and recognition processes in motor memory: effects of feedback and knowledge of results delay

In linear movement tasks of 200 msec (Experiment 1 -ballistic movement) and 500 msec (Experiment 2 - nonballistic movement), motor recall strength was assessed by absolute, constant, and variable error; recognition strength was assessed by Z'-transformed actual-estimate correlations and absolute actual-estimate difference scores. Contrary to predictions, neither increased KR delay (45 vs. 5 sec) nor limited visual-auditory-tactile feedback caused decrements in recognition processes over KR-training or KR-withdrawal trial blocks for the 200-msec task. In the 500-msec task, the independent variables impaired recognition through training and transfer trials but impaired recall only in the training trials. Results generally did not support the hypothesized independence between recall and recognition processes. Several methodological issues related to recall, and recognition research were discussed.     

Influences of closure,occlusion, and size on the perception of fragmented pictures

Two experiments examined the ability to recognize a repeated figure in stimuli where only fragments of the figures were presented. Fragments were either closed or open regions presented either with or without an occluder that filled the spaces between the fragments (Experiment 1). Recognition performance was significantly better for open fragments, with or without an occluder, contrary to previous assertions that the occluder is the important factor for recognition. When stimulus size was varied, an occluder hindered recognition performance in the smallest size condition relative to unoccluded stimuli, which were equally easy to recognize across all size conditions (Experiment 2). The size results support the idea of size invariance in object naming. The difficulty in the smallest occluded condition is discussed in terms of differences in global and local processing depending on visual angle and sparsity