No pain, no gain? Associations of athletic participation with capability for suicide among college students.

INTRODUCTION: Suicide is a leading cause of death among college students. In order to advance understanding of suicide risk factors in this population, the present study provides a theoretically grounded test of associations between experiences in sports and both facets of capability for suicide (i.e., fearlessness about death and pain tolerance). Secondarily, the present study aimed to explore possible distinctions between subjective and objective pain tolerance. METHODS: Undergraduate students (N = 153) completed the study at a single timepoint. A pressure algometer was used to measure objective pain tolerance, and self-report questionnaires assessed subjective pain tolerance, fearlessness about death (FAD), sports participation, sports-related injuries, level of contact in sport, and weight manipulation practices for sport. RESULTS: Athletes had greater capability for suicide (i.e., higher objective and subjective pain tolerance and greater FAD) relative to non-athletes. Sports-related injuries were positively associated with both FAD and subjective pain tolerance, and level of contact in sport was positively associated with FAD. Objective and subjective pain tolerance were moderately correlated. CONCLUSIONS: Sports-related injuries and level of physical contact in athletics are associated with the facets of capability for suicide among college student athletes. Discrepancies in results between subjective and objective pain tolerance suggest important distinctions between these constructs.

Cerebral white matter connectivity, cognition, and age-related macular degeneration.

Age-related macular degeneration (AMD) is a common retina disease associated with cognitive impairment in older adults. The mechanism(s) that account for the link between AMD and cognitive decline remain unclear. Here we aim to shed light on this issue by investigating whether relationships between cognition and white matter in the brain differ by AMD status. In a direct group comparison of brain connectometry maps from diffusion weighted images, AMD patients showed significantly weaker quantitative anisotropy (QA) than healthy controls, predominantly in the splenium and left optic radiation. The QA of these tracts, however, did not correlate with the visual acuity measure, indicating that this group effect is not directly driven by visual loss. The AMD and control groups did not differ significantly in cognitive performance.Across all participants, better cognitive performance (e.g. verbal fluency) is associated with stronger connectivity strength in white matter tracts including the splenium and the left inferior fronto-occipital fasciculus/inferior longitudinal fasciculus. However, there were significant interactions between group and cognitive performance (verbal fluency, memory), suggesting that the relation between QA and cognitive performance was weaker in AMD patients than in controls.This may be explained by unmeasured determinants of performance that are more common or impactful in AMD or by a recruitment bias whereby the AMD group had higher cognitive reserve. In general, our findings suggest that neural degeneration in the brain might occur in parallel to AMD in the eyes, although the participants studied here do not (yet) exhibit overt cognitive declines per standard assessments.

Change blindness for cast shadows in natural scenes: Even informative shadow changes are missed.

Previous work has shown that human observers discount or neglect cast shadows in natural and artificial scenes across a range of visual tasks. This is a reasonable strategy for a visual system designed to recognize objects under a range of lighting conditions, since cast shadows are not intrinsic properties of the scene-they look different (or disappear entirely) under different lighting conditions. However, cast shadows can convey useful information about the three-dimensional shapes of objects and their spatial relations. In this study, we investigated how well people detect changes to cast shadows, presented in natural scenes in a change blindness paradigm, and whether shadow changes that imply the movement or disappearance of an object are more easily noticed than shadow changes that imply a change in lighting. In Experiment 1, a critical object's shadow was removed, rotated to another direction, or shifted down to suggest that the object was floating. All of these shadow changes were noticed less often than changes to physical objects or surfaces in the scene, and there was no difference in the detection rates for the three types of changes. In Experiment 2, the shadows of visible or occluded objects were removed from the scenes. Although removing the cast shadow of an occluded object could be seen as an object deletion, both types of shadow changes were noticed less often than deletions of the visible, physical objects in the scene. These results show that even informative shadow changes are missed, suggesting that cast shadows are discounted fairly early in the processing of natural scenes.