The origin of conditional logic: does a cheater detection module exist?

The domain-specific hypothesis of L. Cosmides (1989) and L. Cosmides and J. Tooby (1989, 1992) positing that conditional logic has its origin in the evolution of social exchange and in the detection of potential cheaters was tested against a more domain-general hypothesis positing that adult reasoning is logical and that errors in conditional reasoning arise from misunderstandings, not from a lack of logicality. The results of 5 experiments with undergraduate students (n = 682 for Experiments 1-4; n = 188 for Experiment 5), which involved a series of selection tasks that yielded specific predictions about participant performance, were not consistent with the cheater detection hypothesis. Findings supported the misunderstandings hypothesis and imply that adults possess general-purpose logical competence versus domain-specific modules.     

Site-selective N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate antagonists produce distinct effects in rats performing complex discriminations

Glutamate receptor-dependent neural plasticity is thought to be implicated in memory processes. Ionotropic N-methyl-D-aspartate- (NMDA) sensitive and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate- (AMPA) sensitive glutamate receptors have been particularly studied for their role in synaptic plasticity. Drugs can alter AMPA and NMDA receptor neurotransmission by competing for the glutamate site or other sites on these receptor proteins. Variants of the protein subunits forming AMPA and NMDA heteromers contribute to the complexity of pharmacological activity at these receptors. The NMDA receptor has numerous modulatory centers, including the glycine binding site, NR2B protein specific binding site, and an intrachannel (PCP) binding site. In this study, the accuracy and rate of rats performing under a Fixed Consecutive Number (FCN) operant task were measured after administrations of site-selective AMPA and NMDA receptor modulators. Test compounds included two glycine site NMDA agonists [(+)HA 966 and D-cycloserine], two NR2-B site NMDA antagonists (eliprodil and ifenprodil), an NMDA channel blocking antagonist (MK 801), and a competitively acting AMPA receptor antagonist (NBQX). The accuracy of FCN performance was not affected by response-rate-altering doses of (+) HA 966, D-cycloserine, eliprodil, ifenprodil, or NBQX. MK 801, on the other hand, reduced performance accuracy at several doses. These results are consistent with earlier studies suggesting that AMPA antagonists minimally affect working memory and that glycine and NR2B protein-specific modulatory sites may have advantages as targets for the development of medications intended to alter NMDA receptor-mediated transmission.     

Adaptive motor behavior of cerebellar patients during exposure to unfamiliar external forces

The authors investigated adaptation of goal-directed forearm movements to an unknown external viscous force assisting forearm flexion in 6 patients with cerebellar dysfunction and in 6 control participants. Motor performance was generally degraded in cerebellar patients and was markedly reduced under the force condition in both groups. However, patients and controls were able to adapt to the novel force within 8 trials. Only the healthy controls were able to improve motor performance when readapting to a null-force condition. The results indicate that cerebellar patients' motor control system has imprecise estimations of actual limb dynamics at its disposal. Force adaptation may have been preserved because single-joint movements were performed, whereas the negative viscous force alone and no interaction forces had to be compensated.     

Exploring Latent Profiles of Psychopathology in a Sample of Lonely People Seeking Treatment

Journal of Psychopathology and Behavioral Assessment - Loneliness is a common experience in populations experiencing mental health problems. Associations with symptoms of psychopathology are...     

A response to Penrose’s “Sandel on enhancement: A response to Van Niekerk”

In this article the author responds to Brian Penrose’s critical response to his (Van Niekerk’s) article “Biomedical enhancement and the pursuit of mastery and perfection: a critique of the views of Michael Sandel” that appeared in the PSSA conference edition of the SAJP 33(2), 2014. While Van Niekerk is appreciative of the opportunity for spirited dialogue that Penrose’s response provides, he nevertheless takes issue with several charges Penrose raises. He responds to Penrose’s claims that Van Niekerk does not fully understand “the Sandel project” and thus that Van Niekerk creates and shoots down a straw man in his argument against Sandel. Van Niekerk argues that Penrose’s claims are indicative of significant methodological differences between their respective approaches. Penrose acknowledges the “fuzziness” of Sandel’s arguments with regards to biomedical enhancement. He then develops an interpretation of Sandel’s views that claims to have “filled in the complete picture” of what Sandel attempts to do, and then reproaches Van Niekerk for not responding to that “completed picture”, i.e. the “Sandel project”. Van Niekerk finds this to be an unreasonable and methodologically highly problematic demand on him. Van Niekerk responds to a number of Penrose’s arguments, and then concludes that while there are, of course, good reasons to exercise caution at the prospect of biomedical enhancement with regard to its risks, the possibilities offered by enhancement need not elicit a prima facie reaction of pessimism. Rather, such prospects can also be regarded in a positive light as an exciting opportunity to take our own evolution in hand.     

Self-directedness and the susceptibility to distraction by saliency

People with low Self-directedness (SD) tend to explain their behaviour as being significantly influenced by events in the external environment. One important dimension of external cues is their level of salience: highly salient external stimuli are more likely to capture attention, even when such stimuli are not relevant to goals. We examined whether adults reporting low SD would exhibit greater susceptibility to distraction by highly salient external stimuli. Fifty-four (42 males) subjects completed the Attention Modulation by Salience Task (AMST) measuring reaction times to early- or late-onset auditory stimuli in the presence of high- or low-salience visual distractors. SD was assessed via self-report, and analyses tested the relationship between SD and performance on the AMST. Results showed a slowed early response to auditory cues during high salience compared to low salience. Indeed, individuals reporting low SD showed stronger salience interference, suggesting that external causality attribution is accompanied by a subconscious perceptual deficit.     

Effects of NMDA receptor channel blockade on aggression in isolated male mice

N‐Methyl‐D ‐aspartate (NMDA) receptor antagonists are perspective candidates for medication development for a number of diseases/states that are associated with increased aggressiveness (e.g., opioid withdrawal). The prototypic NMDA receptor antagonist phencyclidine (PCP) itself is a widely abused substance and is known to elevate levels of aggression in drug users. The present study was aimed at testing several drugs that share with PCP the ability to block NMDA receptor–associated channel. The resident‐intruder procedure was used to assess drug effects on aggressive behavior in isolated male mice. Resident aggressive mice were administered NMDA channel blockers (PCP; 0.3–10 mg/kg), dizocilpine (MK‐801; 0.01–0.3 mg/kg), memantine (1–30 mg/kg), and MRZ 2/579 (0.1–5.6 mg/kg). The competitive NMDA receptor antagonist D CPPene (0.1–5.6 mg/kg) was also tested as a compound representing an alternative approach to reduce activity of NMDA receptor complex. PCP, dizocilpine, and memantine inhibited expression of aggressive behaviors only at doses that produced ataxia. The novel channel blocker MRZ 2/579 also produced ataxia at the highest dose level but failed to affect aggressiveness. Reduction in aggression with a corresponding increase in sociability was observed after administration of D ‐CPPene. Overall, the present results suggest that NMDA receptor channel blockers do not exert selective effects on aggressive behavior. Aggr. Behav. 25:381–396, 1999. © 1999 Wiley‐Liss, Inc.     

Comparison of impulsiveness, venturesomeness and empathy (I7) structure in English and Spanish samples: Analysis of different structural equation models

The present study analyzed the factorial structure of the I₇ Impulsiveness questionnaire (Impulsiveness, Venturesomeness and Empathy) with a Spanish sample of 742 males and 1.075 females, through exploratory and confirmatory factorial analysis. In relation to the original English data, a three-factor structure showed global congruency coefficients of 0.92 and 0.94 for men and women. Venturesomeness had a modest congruency for males (0.83). A cross-validation analytical strategy showed that the 24-item I₇ was invariant only for the female sample. A subsequent exploratory factor analysis with 24 items showed a sound factor structure. The 24-item version showed the best and most robust structure and similar internal consistency coefficients in regard to the 54-item version. No important differences were founded between I₇ long and short versions with impulsiveness scales of ZKPQ, BIS-10 and SPSRQ.     

The cross-cultural generalizability of Zuckerman's alternative five-factor model of personality

The aim of this study was to analyze the cross-cultural generalizability of the Alternative five-factor model (AFFM; Zuckerman, Kuhlman, & Camac, 1988). The total sample was made up of 9,152 subjects from six countries: China, Germany, Italy, Spain, Switzerland, and the United States. The internal consistencies for all countries were generally similar to those found for the normative American sample. Factor analyses within cultures showed that the normative American structure was replicated in all cultures; however, the congruence coefficients were slightly lower in China and Italy. A similar analysis at the facet level confirmed the high cross-cultural replicability of the AFFM. Mean-level comparisons did not always show the hypothesized effects. The mean score differences across countries were very small.