Characterizing the musical phenotype in individuals with Williams Syndrome.

Williams Syndrome (WS), a neurodevelopmental genetic disorder, is characterized by peaks and valleys in mental function: substantial impairments in cognitive domains such as reasoning, arithmetic ability, and spatial cognition, alongside relatively preserved skills in social domains, face processing, language, and music. We report the results of a comprehensive survey on musical behaviors and background administered to the largest sample of individuals with WS to date (n = 118, mean age = 20.4), and compare the results to those obtained from a control group of typically developing normal individuals (n = 118, mean age = 20.9) and two groups of individuals with other neurodevelopmental genetic disorders, Autism (n = 30, mean age = 18.2) and Down Syndrome (n = 40, mean age = 17.2). Individuals with WS were found to be rated higher in musical accomplishment, engagement, and interest than either of the comparison groups, and equivalent on most measures to the control group. Compared to all other groups including the controls, the WS individuals displayed greater emotional responses to music, manifested interest in music at an earlier age, and spent more hours per week listening to music. In addition, the effects of music listening (whether positive or negative) tended to last longer in the WS group. A factor analysis extracted seven principal components that characterize the musical phenotype in our sample, and discriminant function analysis of those factors was able to successfully predict group membership for the majority of cases. We discuss the neurobiological implications of these findings.     

Lehrer's Case Against Foundationalism

In this essay, I assess Keith Lehrer's case against Foundationalism, which consists of variations on three objections: The Independent Information or Belief Objection, The Risk of Error Objection, and the Hidden Argument Objection. I conclude that each objection fails for reasons that can be endorsed – indeed, I would say for reasons that should be endorsed – byantifoundationalists and foundationalists alike.     

Discrimination between hopes and expectancies for nonvolitional outcomes: psychological phenomenon or artifact?

Despite the large literature concerning the impact of hope and expectancy on various outcomes (e.g., nonvolitional), less is known about the constructs of hope and expectancy themselves. In a recent study, Montgomery et al. (2003) demonstrated that hopes and expectancies are separate but related constructs; however, because both hopes and expectancies were measured within the same context, it is possible that these findings were simply a methodological artifact. Furthermore, it is unknown whether these data would generalize to other populations. Taking into account the importance of this distinction for both the expectancy and hope literatures, the present study sought to: (1) Determine if the distinction between hope and expectancy is a general and reliable phenomenon by using a culturally different sample (i.e., Romanian sample); and (2) Examine the robustness of this distinction by controlling for the context effect. One hundred-twenty five volunteers completed items in regard to 10 nonvolitional outcome scenarios in one of five measurement contexts. The results revealed that hope and expectancy were distinct constructs (p<0.0001), and that this distinction is both general and robust across contexts. Implications for theory and research are discussed.     

Error discounting in probabilistic category learning

The assumption in some current theories of probabilistic categorization is that people gradually attenuate their learning in response to unavoidable error. However, existing evidence for this error discounting is sparse and open to alternative interpretations. We report 2 probabilistic-categorization experiments in which we investigated error discounting by shifting feedback probabilities to new values after different amounts of training. In both experiments, responding gradually became less responsive to errors, and learning was slowed for some time after the feedback shift. Both results were indicative of error discounting. Quantitative modeling of the data revealed that adding a mechanism for error discounting significantly improved the fits of an exemplar-based and a rule-based associative learning model, as well as of a recency-based model of categorization. We conclude that error discounting is an important component of probabilistic learning.     

Training Experiences as Mediators of the Association Between Gender-Role Egalitarianism and Women��s Adjustment to Marine Recruit Training

Women may face particular challenges adjusting to the military environment, in part due to their numerical minority status in a traditionally male culture. In addition, women are more likely than men to experience the added stressor of sexual harassment. We examined several potential mediators of the relationship between gender-role egalitarianism and adjustment to boot camp training in a sample of 658 female U.S. Marine recruits. Results indicated that sexual harassment, performance stress, and unit cohesion mediated the relationship between egalitarianism and mental health symptomatology. These findings suggest that beliefs about gender roles are important to consider in efforts to improve women??s adjustment in the military.     

Response-time tests of logical-rule models of categorization

A recent resurgence in logical-rule theories of categorization has motivated the development of a class of models that predict not only choice probabilities but also categorization response times (RTs; Fifi?, Little, & Nosofsky, 2010). The new models combine mental-architecture and random-walk approaches within an integrated framework and predict detailed RT-distribution data at the level of individual participants and individual stimuli. To date, however, tests of the models have been limited to validation tests in which participants were provided with explicit instructions to adopt particular processing strategies for implementing the rules. In the present research, we test conditions in which categories are learned via induction over training exemplars and in which participants are free to adopt whatever classification strategy they choose. In addition, we explore how variations in stimulus formats, involving either spatially separated or overlapping dimensions, influence processing modes in rule-based classification tasks. In conditions involving spatially separated dimensions, strong evidence is obtained for application of logical-rule strategies operating in a serial-self-terminating processing mode. In conditions involving spatially overlapping dimensions, preliminary evidence is obtained that a mixture of serial and parallel processing underlies the application of rule-based classification strategies. The logical-rule models fare considerably better than major extant alternative models in accounting for the categorization RTs.