Cultural Diversity and Patients with Reduced Capacity: The Use of Ethics Consultation to Advocate for Mentally Handicapped Persons in Living Organ Donation

Theoretical Medicine and Bioethics - Living organ donation will soon become the source of the majority of organs donations for transplant. Should mentally handicapped people be allowed to donate,...     

A New View of Meditation

After years of meditating, are you still saddled with many of the same personal conflicts and interpersonal inhibitions that plagued you before you began? Rubin explores the hidden flaws in the meditative method itself. He explores Buddhism's ambivalent relationship to emotional life, and the negative consequences of letting go of experience. Detaching from experience may result in renouncing vital aspects of ourselves, such as constructive passion. The author argues that real meditation is transformative not tranquilizing, fostering a dynamic way of living.     

Auditory spatial attention capture,disengagement, and response selection in normal aging

Attention control is a core element of cognitive aging, but the specific mechanisms that differ with age are unclear. Here we used a novel auditory spatial attention task to evaluate stimulus processing at the level of early attention capture, later response selection, and the lingering effects of attention capture across trials in young and older adults. We found that the shapes of spatial attention capture gradients were remarkably similar in young and older adults, but only the older group had lingering effects of attention capture on the next trial. Response selection for stimulus-response incompatibilities took longer in older subjects, but primarily when attending to the midline location. The results suggest that the likelihood and spatial tuning of attention capture is comparable among groups, but once attention is captured, older subjects take longer to disengage. Age differences in response selection were supported, but may not be a general feature of cognitive aging.     

An association between the DAT1 polymorphism and smoking behavior in young adults from the National Longitudinal Study of Adolescent Health.

Associations between smoking behavior and polymorphisms in the dopaminergic genes (DAT1 and DRD2) were tested by using within- and between-family measures of allelic transmission in 2,448 young adults from the National Longitudinal Study of Adolescent Health. The 9-repeat allele of the dopamine transporter gene polymorphism (DAT1) was inversely associated with smoking in samples that included all subjects and only those who had initiated smoking, accounting for approximately 1% of the variance. Never smokers and current nonsmokers had an excess transmission of the 9-repeat allele compared with regular smokers, suggesting a protective effect of the 9-repeat allele, which is hypothesized to alter synaptic dopamine levels.     

Effect of anxiety reduction on children's school performance and social adjustment

This study tested the effect of reductions in children's anxiety over time on improvements in school performance and social functioning in the context of participation in a cognitive-behavioral intervention program. Participants included 40 children with high anxiety (6-13 years of age). Independent evaluators, children, and parents rated child anxiety; parents rated school performance; and children and parents rated social functioning. Measures were completed at preintervention, midintervention, and postintervention. Fixed-effects regression analyses and random-effects regression analyses indicated that decreased anxiety was predictive of improved school performance and social functioning over the course of the intervention. These findings suggest that changes in anxiety influence trajectories of children's scholastic and social functioning.     

Generalization decrement in human contingency learning

An association between a cue and an outcome will generalize to a similar novel cue to some extent, but not completely. Learning theorists refer to the discrepancy between responding elicited by the original cue and the novel cue as a generalization decrement. Two experiments used a contingency learning task with human participants to compare the size of a generalization decrement between configurations of cues that were altered by adding or subtracting compositional elements. The results suggest that adding elements to a configuration can produce a generalization decrement, but removing elements produces a more robust generalization decrement. Furthermore, the generalization decrement caused by adding elements was not likely to be caused by competing orienting responses. The results are used to contrast Pearce's (1987, 1994) and Wagner's (2003) models of stimulus generalization.     

The interplay of memory and judgment processes in effects of aging on hindsight bias

Hindsight bias is the phenomenon that after people are presented with the correct answer to a question, their judgment regarding their own past answer to this question is biased toward the correct answer. In three experiments, younger and older adults gave numerical responses to general-knowledge questions and later attempted to recall their responses. For some questions, the correct answer was provided during recall (Experiment 1) or before recall (Experiments 2 and 3). Multinomial model-based analyses show age differences in both recollection bias and reconstruction bias when the correct judgment was in working memory during the recall phase. The authors discuss implications for theories of cognitive aging and theories of hindsight bias.     

Does energy expenditure affect the perception of egocentric distance? A failure to replicate experiment 1 of Proffitt, Stefanucci, Banton, and Epstein (2003)

In a series of recent studies, Proffitt and his colleagues have reported that the perceived distance to a target is influenced by the energy expenditure associated with any action, such as walking or throwing, for spanning the distance to the target. In particular, Proffitt, Stefanucci, Banton, and Epstein (2003) reported that wearing a heavy backpack caused verbal reports of distance to increase. We conducted a study to determine whether three responses dependent on perceived distance (verbal report of distance, blind walking, and estimates of object size) are influenced by the backpack manipulation. In two experiments, one involving a between-participants design and the other involving a within-participants design, we found that none of the three responses were influenced by the wearing of a heavy backpack.     

Neurorobiology and evidence-based biological treatments for substance abuse disorders

Behavioral patterns of addiction include compulsive drug-seeking, persistent abuse of substances despite the often dire consequences on social functioning and physical health, and the high probability of relapse even after prolonged drug-free periods. The recent focus on the biological basis of addiction has provided evidence to support the hypothesis that behavioral manifestations for addiction are influenced by biological factors, and biological factors often produce behavioral changes that can further increase risk. The current understanding of the role of the dopaminergic, glutamatergic, Upsilon-aminobutyric acidergic, and opioid receptor systems in the pathophysiology of addiction as well as the clinical implications of these systems for new and emerging treatments will be discussed. This article will also review the pharmacologic agents used in the treatment of substance abuse disorders and presents evidence-based data for their safety, efficacy, and feasibility of use in different patient populations.     

Up or down: the influence of upcoming reinforcement on consummatory and operant behavior

Research has shown that animal subjects that are given a chance to consume a low-valued substance will consume less of it if a high-valued substance will soon be available than they would if the low-valued substance were to remain available (negative consummatory contrast). Research has also shown that subjects that lever press for a low-valued reinforcer will press the lever more often for that reinforcer if they will soon be able to lever press for a high-valued reinforcer than they would if they continue to press for the low-valued reinforcer (positive induction). The present study investigated these different changes in behavior across 3 experiments. The results suggest that the occurrence of contrast or induction does not depend on the type of substances that are used. We argue that further investigation of the contrast vs. induction issue is warranted because it has empirical, theoretical, and applied implications.