Molecular Mechanisms Associated with the Benefits of Variable Practice in Motor Learning

Abstract

Variable practice promotes a higher level of motor learning than constant practice. The glutamate receptors, n-methyl-d-aspartate (NMDA) and alfa-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA), have been associated with the changes in motor cortex that occur throughout the process of motor learning. Considering that, it is possible that variable practice is more associated with the NMDA and AMPA receptors than constant practice. This study aimed ao investigating the association between the glutamate receptors, NMDA and AMPA, and constant and variable practice schedules. Seventy-eight male mice practiced the rotarod task in a constant or variable scheduling, in two consecutive days (acquisition phase). Learning tests were performed 24?h and 10?days after the end of the acquisition phase. Variable practice was more associated with the NMDA receptor and had a greater AMPA receptor expression than constant practice. The results suggest that the benefits of variable practice are result of both the greater dependency on the NMDA receptor and the greater AMPA receptor expression.     

Investigating the latent dimensions of posttraumatic stress disorder and the role of anxiety sensitivity in combat-exposed Filipino soldiers

ABSTRACT

Identifying the optimal factor structure of posttraumatic stress disorder (PTSD) has recently been reinvigorated in literature due to the substantial changes to its diagnostic criteria in the fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Currently, six models of PTSD are supported in literature, but there is no consensus on the best-fitting factor structure. Additionally, the extant literature examining the relationship between PTSD symptom-grouping and AS in the latent level has been scarce. The present study’s objectives are two-fold: first, we aimed to identify the best-fitted model of PTSD by comparing the six empirically-supported models, and; second, we examined the relationship between the best-fitting model with anxiety sensitivity (AS). Utilizing a sample of 476 combat-exposed soldiers, the results suggest that both the anhedonia and hybrid models provide the best fit to the data, with the anhedonia model achieving slightly better fit indices. Further, the examination on the influence of AS to PTSD reveal that while there is a pattern of decreasing factor loadings and factor correlations when accounting for AS, the changes are not significant to alter the PTSD symptom-structure. Based on these results, our findings suggest further investigation on the possible mediating or moderating mechanisms by which AS may influence PTSD.     

Spaceship Archeology: Methodological Experiments in NSF Counter-Insurgency at the 2017 Oregon Eclipse Festival

Abstract

This article examines several aspects of knowledge production among practitioners of 21st century capitalism, critiquing the motivations, funding, methods, and dissemination of today’s politically and economically dominant epistemology. We document a methodological experiment undertaken during the Oregon Eclipse Festival—a week-long event coinciding with the solar eclipse that crossed the United States on August 21, 2017. As commissioned participants in the festival’s Art & Science exhibit, we designed an interactive archeological excavation that sought to produce material evidence corroborating the (un)reality of UFO activity in Oregon. From this performance, we highlight four insights into the relationship between science, evidence, and responsibility.     

Social Responsiveness and Objectification: The Moderating Roles of Serotonin Transporter and Serotonin Receptor 2A Genotypes in an Objectification Theory Model of Disordered Eating

Feminist scholars have called for gender researchers to consider gene-environment interactions for gender-imbalanced disorders (Salk and Hyde Psychology of Women Quarterly, 36, 395–411, 2012). Responding to these calls, the present study integrates objectification theory (Fredrickson and Roberts Psychology of Women Quarterly, 21, 173–206, 1997) and genetic research. In the tested model, objectification experiences are associated with disordered eating through body surveillance and body shame, and serotonin transporter (SLC6A4) genotypes (5-HTTLPR and rs25531), serotonin 2A receptor SNP genotypes (HTR2A rs6311), and the epistatic interaction between those genotypes function as moderators. U.S. undergraduate women (n?=?526) completed self-reports of objectification, body surveillance, body shame, and disordered eating and donated buccal cells for genetic analyses. The association between objectification and disordered eating was mediated by body shame, but not body surveillance. The paths from objectification to both body surveillance and body shame were moderated by genotypes. The indirect effect of objectification on disordered eating through body shame was only present for SLC6A4 L′ and rs6311 G homozygotes. Our results are consistent with previous evidence that serotonin system genetic variation is associated with disordered eating risk. They provide evidence of a non-deterministic genetic effect that is context-dependent and subtle. These findings also reinforce efforts to develop personalized prevention and treatment approaches for eating disorders.