Epistemic buck-passing and the interpersonal view of testimony

Two ideas shape the epistemology of testimony. One is that testimony provides a unique kind of knowledge. The other is that testimonial knowledge is a social achievement. In traditional terms, those who affirm these ideas are anti-reductionists, and those who deny them are reductionists. There is increasing interest, however, in the possibility of affirming these ideas without embracing anti-reductionism. Thus, Sanford Goldberg uses the idea of epistemic buck-passing to argue that even reductionists can accept the uniqueness of testimonial knowledge, and Jennifer Lackey gives both speaker and hearer an essential role in testimonial justification, rejecting both reductionism and anti-reductionism in favor of what she calls dualism. After distinguishing a weaker and a stronger notion of buck-passing, we show how anti-reductionists can use the stronger notion to motivate their position, and to answer Goldberg’s and Lackey’s challenges.     

Foot Motion Character During Forward and Backward Walking With Shoes and Barefoot

Abstract

Backward walking (BW) has been extensively used in athletic training and orthopedic rehabilitation as it may have value for enhancing balance. This study identified the differences in foot intersegment kinematics (forward walking (FW) vs. time-reversed BW) and plantar pressure parameters of 16 healthy habitually shod individuals walking FW and BW using flexible shoes (SH) and under barefoot conditions (BF). BW was found to have shorter stride length (SL) and higher stride frequency (SF) under BF conditions compared with SH, which indicates a better BW gait stability under BF conditions. Decreased HX/FF dorsiflexion at HO in BW induces less plantar aponeurosis tension which may inhibit the windlass mechanism compared to FW walking. Increased forefoot relative to hindfoot (FF/HF) pronation and sequentially hindfoot relative to tibia (HF/TB) eversion combined with medially distributed plantar pressure and a higher plantar contact area in the medial side in BW–BF maybe beneficial in maintaining balance. These results indicate that BW training may be more reliable under BF conditions compared to the SH conditions based on greater sensory information feedback from the plantar area resulting in better biomechanical behavior.     

Pathways from Birth Weight to ADHD Symptoms through Fluid Reasoning in Youth with or without Intellectual Disability

Although individual differences in fluid reasoning reliably mediate predictions of attention-deficit/hyperactivity disorder (ADHD) symptoms from birth weight in youth with typical cognitive development (TD), it is unknown if this indirect effect operates similarly in the development of ADHD symptoms secondary to intellectual disability (ID). Thus, we evaluated mediation by fluid reasoning in a longitudinal sample of 163 youth (45% female) with (n = 52) or without (n = 111) ID who were followed prospectively from age 5 to age 13. At age 9, youth completed the Arithmetic subtest of the Wechsler Intelligence Scale for Children, a measure of fluid reasoning. At ages 9 and 13, mothers and teachers separately rated youth ADHD symptoms and mothers completed a diagnostic interview. Mediation was tested via path analysis with bootstrapped confidence intervals, and moderated mediation estimated whether indirect effects differed between ID and TD youth or based on youth IQ. Controlling for demographic factors and age 9 ADHD symptoms, age 9 Arithmetic mediated birth weight and multi-method/informant age 13 ADHD symptoms, such that birth weight positively predicted Arithmetic, which negatively predicted ADHD symptoms. Neither ID status nor IQ moderated the observed indirect effect through Arithmetic, suggesting that it was similar for ID and TD youth as well as across the range of youth IQs. These findings support previous evidence that fluid reasoning, as measured by Arithmetic, may causally mediate birth weight and ADHD symptoms, and suggest that this pathway operates similarly with respect to the development of ADHD symptoms in youth with ID.     

Reasons for substance use among people with psychotic disorders: method triangulation approach

Substance use disorders (SUD) are common among people with psychotic disorders and are associated with many negative consequences. Understanding the reasons for substance use in this population may allow for the development of more effective prevention and intervention strategies. We examined reasons for tobacco, alcohol, or cannabis use among people with psychotic disorders. Sixty-four participants with a diagnosed psychotic disorder completed a self-report reasons for use questionnaire. A subset of eight participants completed semi-structured qualitative interviews. Both the qualitative and quantitative data indicated that reasons for use of tobacco, alcohol, and cannabis differed considerably. Tobacco was primarily used for coping motives, alcohol for social motives, and cannabis for pleasure enhancement motives. Prevention and intervention strategies targeting coexisting psychotic disorders and SUD may improve in effectiveness if they address the perceived beneficial effects of tobacco use, the strong social pressures influencing alcohol use and if they encourage cannabis users to seek alternative pleasurable activities.