Busy doing nothing: Evidence for nonaction-effect binding

Research on voluntary action has focused on the question of how we represent our behavior on a motor and cognitive level. However, the question of how we represent voluntary not acting has been completely neglected. The aim of the present study was to investigate the cognitive and motor representation of intentionally not acting. By using an action-effect binding approach, we demonstrate similarities of action and nonaction. In particular, our results reveal that voluntary nonactions can be bound to an effect tone. This finding suggests that effect binding is not restricted to an association between a motor representation and a successive effect (action-effect binding) but can also occur for an intended nonaction and its effect (nonaction-effect binding). Moreover, we demonstrate that nonactions have to be initiated voluntarily in order to elicit nonaction-effect binding.     

Processing implicit and explicit representations.

This article summarizes the results of a 15-year research program dedicated to understanding how implicitly activated memories affect remembering and proposes a model for describing such influences. Implicit memories are manipulated by varying the number of associates preexperimentally linked to test cues or to studied words. Assumptions of the model specify when implicit memories of various types are likely to contribute to performance in various tasks. The main assumptions are that encoding involves both explicit and implicit processing components and that these components provide mutually exclusive sources of information during testing. Experiments designed to evaluate the exclusivity assumption are reported, and implications of the findings for several theoretical frameworks are discussed.     

Spider-Phobic Children Do Not React with Differential Skin Conductance Responses to Masked Phobic Stimuli

In the present study, spider-phobic children (N = 22) were exposed to subliminal presentations of spiders, snakes, and mushrooms, while skin conductance responses (SCRs) were measured. In addition, pre- and post-treatment symptom severity data were obtained. As a group, spider-phobic children did not react with differential SCRs to masked phobic pictures. In addition, no convincing evidence was found to suggest that individual variation in differential SCRs to phobic stimuli is linked to pre-treatment symptom severity or therapy outcome. These findings cast doubts on the idea that phobics' phenomenal experience of their fear as irrational and uncontrollable is a result of pre-attentive physiological fear activation.     

Social factors influence haloperidol-induced catalepsy in rat

This study employed manipulations which presumably influence social interactions in rats: (1) paired housing with a heavier conspecific and (2) exposure to the odors of other rats. The dependent variable was the akinetic state induced by haloperidol, a neuroleptic and dopamine antagonist. In Experiment 1, adult male Long-Evans hooded rats were matched by weight and caged alone or in pairs with one rat 30 g heavier than its cagemate. All rats received haloperidol (1.5 mg/kg) and catalepsy testing. Heavy rats showed more catalepsy than the lighter member of pairs or weight-matched, singly housed controls. In Experiment 2, adult male rats were left unrecaged or were recaged into cages with bedding recently soiled by females or other adult males. After haloperidol (1.0 mg/kg), the rats exposed to bedding soiled by other adult males showed more catalepsy than did the control groups. Thus, the results of both experiments indicated that social factors can influence the akinesia induced by dopamine antagonists.     

Hiring bias and the disabled interviewee: Effects of manipulating work history and disability information of the disabled job applicant

Ninety MBA students were randomly assigned to one of six experimental conditions in a 3(levels of disability) × 2(levels of employment history) design. Levels of disability (Physical, Psychiatric, and No Disability) and levels of employment history (Good and Poor) were manipulated by giving the subjects bogus information on a job application form prior to hearing a taped job interview. Subjects then rated the quality of the interview and stated the probability that they would hire the interviewee. Evaluations of the interview and hiring probabilities were different between the experimental groups. Implications and suggestions for future research are discussed.     

A role for Synapsin in associative learning: the Drosophila larva as a study case

Synapsins are evolutionarily conserved, highly abundant vesicular phosphoproteins in presynaptic terminals. They are thought to regulate the recruitment of synaptic vesicles from the reserve pool to the readily-releasable pool, in particular when vesicle release is to be maintained at high spiking rates. As regulation of transmitter release is a prerequisite for synaptic plasticity, we use the fruit fly Drosophila to ask whether Synapsin has a role in behavioral plasticity as well; in fruit flies, Synapsin is encoded by a single gene (syn). We tackled this question for associative olfactory learning in larval Drosophila by using the deletion mutant syn^97CS, which had been backcrossed to the Canton-S wild-type strain (CS) for 13 generations. We provide a molecular account of the genomic status of syn^97CS by PCR and show the absence of gene product on Western blots and nerve-muscle preparations. We found that olfactory associative learning in syn^97CS larvae is reduced to ~50% of wild-type CS levels; however, responsiveness to the to-be-associated stimuli and motor performance in untrained animals are normal. In addition, we introduce two novel behavioral control procedures to test stimulus responsiveness and motor performance after “sham training.” Wild-type CS and syn^97CS perform indistinguishably also in these tests. Thus, larval Drosophila can be used as a case study for a role of Synapsin in associative learning.     

Attitudes Toward Affirmative Action as a Function of Racial Identity Among African American College Students

Variations in support for affirmative action were assessed in a sample of 181 African American college students in Massachusetts. These students generally endorsed affirmative action, and endorsement varied positively as a function of the belief that one had personally benefited from affirmative action. Aspects of racial identity, indexed by the Multidimensional Inventory of Black Identity, also predicted variations in attitudes toward affirmative action, over and above background factors and personal benefit. Consistent with realistic group conflict theory, the most influential aspects of identity were centrality (i.e., the degree to which group identity is central to personal identity), private regard (i.e., pride in the group), and an oppressed minority ideology (i.e., a viewpoint that emphasizes the similarities between African Americans and other oppressed groups).     

Suppression of irrelevant activation in the horizontal and vertical Simon task differs quantitatively not qualitatively

The Simon effect is usually explained by the assumption that the irrelevant stimulus location automatically activates the corresponding response. In the case of incongruent stimulus–response assignments automatically activated responses therefore have to be suppressed to ensure correct responses. This account, however, has been called into question for other than horizontally arranged visual Simon tasks. We investigated whether there is a qualitative or quantitative difference in suppression of irrelevant activation between horizontally and vertically arranged Simon tasks, using delta-function analyses. Sequential analyses revealed suppression after incongruent trials in both tasks, supporting the idea of a quantitative rather than a qualitative difference between the tasks. We conclude that automatic response activation is weaker in vertical tasks resulting in lower inhibitory demands as compared to horizontal tasks.