Set size,assertion form,thematic content and sampling in the selection task

Participants attempted to solve a modified version of Wason's (1966) selection task. Variables were: (1) sizes of the sets referenced by a specified assertion, (2) form of the assertion (conditional or categorical), (3) thematic content of the assertion (letters and numbers or makes and owners of taxicabs), and (4) the need for sampling or not. In Experiment 1, participants were given enough information to determine the truth or falsity of the specified assertion with certainty; in Experiment 2, they had to rely on sampling and could not determine the assertion's truth or falsity with certainty. Performance was better in Experiment 1 than in Experiment 2, but in both cases much better than what is typically obtained with the conventional selection task. The results support the hypothesis that performance of the selection task is sensitive to the sizes of the sets involved, add credence to the conclusion that framing the task in a thematically meaningful way can facilitate performance, and demonstrate that facilitation does not require deontic reasoning or a well-known convention being involved. The relationship between expressed confidence and level of performance is consistent with other studies showing the former to be a good predictor of the latter.     

Is a lower dose of cyproterone acetate as effective at testosterone suppression in transgender women as higher doses?

Objective: The recommended dose of cyproterone acetate (CPA), an anti-androgen that is commonly used in the hormonal treatment of transgender women, is 50–100 mg daily. Our objective was to determine whether CPA at 25 mg daily would suppress total testosterone as effectively as 50 mg daily in transgender women.

Methods: We conducted a retrospective cohort analysis of transgender women attending an endocrinology clinic between April 1, 2009, and June 30, 2015. We used a generalized linear mixed model to compare total testosterone between patients on CPA 25 mg versus CPA 50 mg or higher. In a subgroup of patients for which the CPA dose was decreased from 50 mg to 25 mg, we compared total testosterone levels before and after the decrease.

Results: We divided the sixty-eight patients included in the study into 4 groups: group 1, CPA 25 mg (N =31); group 2, CPA 50 mg or higher (N = 19); group 3, CPA dose lowered from 50 mg to 25 mg (N = 15); group 4, CPA dose increased from 25 mg to 50 mg (N = 3). The mean total testosterone on treatment was 0.9 nmol/L (95% CI 0.7 to 1.1) in group 1 and 1.2 nmol/L (95% CI 0.9–1.5) in group 2 and were not significantly different (p = 0.087). In group 3, there was no significant difference between total testosterone levels before and after decreasing the dose of CPA from 50 mg to 25 mg, p = 0.86. Group 4 was excluded from analysis.

Conclusions: We found that 25 mg of CPA daily was effective at suppressing testosterone levels to within normal female range when used in combination with recommended estrogen therapy in transgender women. Clinicians should consider using a lower dose of CPA in order to minimize potential adverse effects.     

Striving for optimal relevance when answering questions

When people are asked "Do you have the time?" they can answer in a variety of ways, such as "It is almost 3", "Yeah, it is quarter past two", or more precisely as in "It is now 1:43". We present the results of four experiments that examined people's real-life answers to questions about the time. Our hypothesis, following previous research findings, was that people strive to make their answers optimally relevant for the addressee, which in many cases allows people to give rounded, and not exact, time responses. Moreover, analyses of the non-numeral words, hesitations, and latencies of people's verbal responses to time questions reveal important insights into the dynamics of speaking to achieve optimal relevance. People include discourse markers, hesitation marks, like "uh" and "um", and pauses when answering time questions to maximize the cognitive effects (e.g., a rounded answer is adequate) listeners can infer while minimizing the cognitive effort required to infer these effects. This research provides new empirical evidence on how relevance considerations shape collaborative language use.     

Incremental validity of the Psychopathy Checklist facet scores: predicting release outcome in six samples

The incremental validity of the 4 facet scores (Interpersonal, Affective, Lifestyle, Antisocial) of the Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991, 2003) and the Psychopathy Checklist: Screening Version (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995) was evaluated in 6 forensic/correctional samples with average follow-ups ranging from 20 weeks to 10 years. Results indicated that whereas Facet 4 (Antisocial) achieved incremental validity relative to the first 3 facets (Interpersonal, Affective, and Lifestyle) in predicting recidivism in all 6 samples, a block of the first 3 facets achieved incremental validity relative to the 4th facet in only 1 sample. Thus, although there was consistent support for the incremental validity of Facet 4 above and beyond the first 3 facets, there was minimal support for the incremental validity of Facets 1, 2, and 3 above and beyond Facet 4. The implications of these findings for the psychopathy construct in general and the PCL-R/SV in particular are discussed.     

Abdominal exercise intensities on firm and compliant surfaces

Muscle activities at 15 sites were compared within a group of healthy young adults to evaluate their relative intensities during six abdominal exercises: partial and full sit-ups on a firm surface (floor) and on an exercise ball that was either stabilized or unstabilized. The most strenuous abdominal exercise overall (i.e., whole body workout) was the full sit-up on a firm surface which included significant muscle activities in the lower extremities. Exercise intensity was also high in the full and partial sit-ups when performed on a ball. The partial sit-up on the floor was the least strenuous of the six exercises. The greatest effect on the abdominal muscles was observed in the partial sit-up on a ball (stabilized and unstabilized). Results suggest that, although abdominal exercises on a ball may be gentler on the hip and lower back, overall exercise intensity is not necessarily lower than that on the floor. Moreover, partial sit-ups, both on the floor and on a ball, also required greater neck muscle activities than full sit-ups. In deciding what type of sit-up to do, exercise surface and different muscular activities between the partial and full sit-ups should be considered.     

Consistent haptic feedback is required but it is not enough for natural reaching to virtual cylinders

In virtual reality it is easy to control the visual cues that tell us about an object's shape. However, it is much harder to provide realistic virtual haptic feedback when grasping virtual objects. In this study we examined the role of haptic feedback when grasping (virtual) cylinders with an elliptical circumference. In Experiment 1 we placed the same circular cylinder at the simulated location of virtual elliptical cylinders of varying shape, so that the haptic feedback did not change when the visually specified shape changed. We found that the scaling of maximum grip aperture with the diameter of the nearest principal axis (.14+/-.04) was much weaker than when grasping real cylinders (.54+/-.04, Cuijpers, Brenner, & Smeets, 2006 Grasping reveals visual misjudgements of shape. Experimental Brain Research, 175, 32-44). For the scaling of grip orientation with the orientation of the cylinder we found large individual differences: the range is .07-.82 (average .42+/-.07) as compared to .55-.79 (average .67+/-.03) for grasping real cylinders. In Experiment 2 we provided consistent haptic feedback by placing real cylinders that matched the location, shape and orientation of the virtual cylinders. The scaling gains of both maximum grip aperture (.39+/-.04) and grip orientation (.56+/-.08) were substantially higher than in Experiment 1, but still lower than for grasps to real cylinders. The variability between participants for the scaling of grip orientation was also much reduced. These results showed that although haptic feedback must be consistent with visual information, it is not sufficient for natural prehension. We discuss the implications of these findings in terms of the integration of visual information with haptic feedback.     

The role of white matter hyperintensities and medial temporal lobe atrophy in age-related executive dysfunctioning

Various studies support an association between white matter hyperintensities (WMH) and deficits in executive function in nondemented ageing. Studies examining executive functions and WMH have generally adopted executive function as a phrase including various functions such as flexibility, inhibition, and working memory. However, these functions include distinctive cognitive processes and not all may be affected as a result of WMH. Furthermore, atrophy of the medial temporal lobe (MTA) is frequently observed in ageing. Nevertheless, in previous studies of nondemented ageing MTA was not considered when examining a relationship between white matter and executive function. The goal of the present study was to examine how WMH and MTA relate to a variety of executive functions, including flexibility, fluency, inhibition, planning, set shifting, and working memory. Strong correlations were observed between WMH and MTA and most of the executive functions. However, only MTA was related to flexibility and set shifting performance. Regression analysis furthermore showed that MTA was the strongest predictor of working memory, after which no further significant association with WMH was noted. Alternatively, both MTA and periventricular hyperintensities independently predicted inhibition performance. These findings emphasize the importance of MTA when examining age-related decline in executive functioning.