A mixed-handed advantage in episodic memory: A possible role of interhemispheric interaction

Recent behavioral and brain imaging data indicate that performance on explicit tests of episodic memory is associated with interaction between the left and right cerebral hemispheres, in contrast with the unihemispheric basis for implicit tests of memory. In the present work, individual differences in strength of personal handedness were used as markers for differences in hemispheric communication, with mixed-handers inferred to have increased interhemispheric interaction relative to strong right-handers. In Experiment 1, memory for words was assessed via recall or word fragment completion. In Experiment 2, memory for real-world events was assessed via recall. Results supported the hypothesis, in that mixed-handers displayed better episodic memory in comparison with strong right-handers.     

Identity and emergency intervention: how social group membership and inclusiveness of group boundaries shape helping behavior

Two experiments exploring the effects of social category membership on real-life helping behavior are reported. In Study 1, intergroup rivalries between soccer fans are used to examine the role of identity in emergency helping. An injured stranger wearing an in-group team shirt is more likely to be helped than when wearing a rival team shirt or an unbranded sports shirt. In Study 2, a more inclusive social categorization is made salient for potential helpers. Helping is extended to those who were previously identified as out-group members but not to those who do not display signs of group membership. Taken together, the studies show the importance of both shared identity between bystander and victim and the inclusiveness of salient identity for increasing the likelihood of emergency intervention.     

Factor structure and validity of the MacArthur Competence Assessment Tool-Criminal Adjudication

Examination of the available literature regarding the development of the MacArthur Competence Assessment Tool-Criminal Adjudication (MacCAT-CA) reveals 2 theoretical factor structures on which the MacCAT-CA was based: one in which 3 lower-order constructs are proposed (understanding, reasoning, appreciation) and one in which 2 higher-order constructs are proposed (competence to assist counsel and decisional competence). Confirmatory factor analyses were conducted with the MacCAT-CA's original normative sample (N = 729) to test both the relative fit of these 2 theoretical factor structures and models that combine the 2 factor structures. Analyses were also completed to examine the convergent and discriminant validity of the MacCAT-CA. Results are discussed in terms of the strengths and weaknesses of the nomothetic nature of the MacCAT-CA.     

Compatibility effects based on stimulus and response numerosity

Four choice reaction time experiments documented a stimulus-response (S-R) compatibility effect involving the numbers of stimuli and responses. In Experiment 1, the stimulus consisted of one or two tones, and the correct response was either one or two taps of a response key. Responses were much faster with a compatible S-R assignment, in which the number of taps matched the number of tones, than with an incompatible assignment in which these numbers mismatched. Experiments 2 and 3 replicated this effect, using visual stimuli and bimodal stimuli, respectively, suggesting that auditory/manual rhythmic compatibility is not essential to it. Experiment 4 showed that an analogous but smaller effect is obtained when stimuli are the digits 1 and 2. This new numerosity-based compatibility effect has general theoretical implications regarding the mechanisms responsible for compatibility effects and practical implications for interface design.     

Enhancement of auditory fear conditioning after housing in a complex environment is attenuated by prior treatment with amphetamine

Prior exposure to drugs of abuse has been shown to occlude the structural plasticity associated with living in a complex environment. Amphetamine treatment may also occlude some cognitive advantages normally associated with living in a complex environment. To test this hypothesis we examined the influence of prior exposure to amphetamine on fear conditioning in rats housed in either a standard or complex environment. Housing in a complex environment facilitated fear learning to an auditory conditioned stimulus (CS), but not to the training context, relative to animals housed singly or in a social group. Prior treatment with amphetamine eliminated this effect. These results indicate that living in a complex environment facilitates conditional freezing to an auditory CS, and that this effect is abolished by pretreatment with amphetamine.     

What is the prevalence of adult ADHD? Results of a population screen of 966 adults

To provide a better estimate of the prevalence of ADHD in adulthood, the authors complete a telephone survey of 966 randomly selected adults. They compute two diagnoses from the survey data. Participants meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for both childhood and adulthood are defined as narrow ADHD. Broad ADHD adds to that definition those meeting subthreshold criteria. Cronbach's alpha is .90 for the 18 DSM-IV symptoms in childhood and .88 when rated for current symptoms in adulthood. No one item unduly influences the reliability of the total score. The authors find similar results in separate analyses of hyperactive-impulsive and inattentive symptoms. They estimate prevalences of 2.9% for Narrow ADHD and 16.4% for Broad ADHD. Having ADHD is associated with lower levels of education and employment status. These findings suggest that adult ADHD is a common disorder associated with impaired functioning.     

Peter Singer’S Argument for Utilitarianism

The paper begins by situating Singer within the British meta-ethical tradition. It sets out the main steps in his argument for utilitarianism as the ‘default setting’ of ethical thought. It argues that Singer’s argument depends on a hierarchy of reasons, such that the ethical viewpoint is understood to be an adaptation – an extension – of a fundamental self-interest. It concludes that the argument fails because it is impossible to get from this starting-point in self-interest to his conception of the ethical point of view. The fundamental problem is its mixing the immiscible: the Humean subordination of reason to interest with the Kantian conception of reason as universal and authoritative.     

Use of interactive voice response (IVR) technology in health research with children

This article reports on the feasibility of using interactive voice response (IVR) technology to obtain daily reports of attitudes toward alcohol and tobacco use among children 9–13 years of age. Two studies were conducted. The first was an investigation of the use of IVR technology to obtain daily data from a sample of primary school children over a period of 8 weeks. The second was an extension of the research to a large sample of primary and secondary school children in urban and rural areas who provided daily data over a 4-week period. Retention and compliance rates comparable to those obtained with adults were evident in both studies, supporting the feasibility of this technology with children. The results are discussed in relation to the benefits of this methodology for health research, particularly for studies of sensitive topics conducted with children and adolescents.