How do college student-athletes’ understanding and expectations of mindfulness and self-compassion change through an intervention?

In the last two decades, mindfulness has permeated sport, exercise, and performance psychology (SEPP). Mindfulness research in SEPP primarily focuses on the efficacy of manualized protocols on various outcomes related to performance and wellbeing; how athletes understand this complex construct, though, is largely unexplored in the literature. Additionally, some researchers suggest that the potentially paradoxical adoption of mindfulness in Western psychology may be contributing to limited outcomes, low engagement in, and poor adherence to mindfulness-based interventions (MBIs). In addition, the exploration of self-compassion as a mechanism for change through mindfulness practice has increased in recent years, making it an important component to consider. The purpose of the present study was to investigate what college student-athletes (SAs) expect to gain from participating in a MBI, how they understand the concepts of mindfulness and self-compassion, and how these expectations and understandings change from beginning to end of an intervention. Intervention supported shifts in understanding were viewed through a constructivist-interpretivist lens. Individual interviews (n = 42) were conducted with all SAs on an NCAA DII swim team at the beginning and end of a 7-week MBI. Reflexive thematic analysis revealed multiple levels of change across members of the team, indicating that expectations may be tied to outcomes, and understanding may be a limiting factor for perceived outcomes. Results provide some evidence that SA expectations and understanding of mindfulness and self-compassion may be related to ambiguity caused by the blending of traditional Eastern mindfulness with Western psychological interventions

Signal detection in animal psychoacoustics: analysis and simulation of sensory and decision-related influences

Signal detection theory (SDT) provides a framework for interpreting psychophysical experiments, separating the putative internal sensory representation and the decision process. SDT was used to analyse ferret behavioural responses in a (yes–no) tone-in-noise detection task. Instead of measuring the receiver-operating characteristic (ROC), we tested SDT by comparing responses collected using two common psychophysical data collection methods. These (Constant Stimuli, Limits) differ in the set of signal levels presented within and across behavioural sessions. The results support the use of SDT as a method of analysis: SDT sensory component was unchanged between the two methods, even though decisions depended on the stimuli presented within a behavioural session. Decision criterion varied trial-by-trial: a ‘yes’ response was more likely after a correct rejection trial than a hit trial. Simulation using an SDT model with several decision components reproduced the experimental observations accurately, leaving only ∼10% of the variance unaccounted for. The model also showed that trial-by-trial dependencies were unlikely to influence measured psychometric functions or thresholds. An additional model component suggested that inattention did not contribute substantially. Further analysis showed that ferrets were changing their decision criteria, almost optimally, to maximise the reward obtained in a session. The data suggest trial-by-trial reward-driven optimization of the decision process. Understanding the factors determining behavioural responses is important for correlating neural activity and behaviour. SDT provides a good account of animal psychoacoustics, and can be validated using standard psychophysical methods and computer simulations, without recourse to ROC measurements

Loss of auditory sensitivity from inner hair cell synaptopathy can be centrally compensated in the young but not old brain

AbstractA dramatic shift in societal demographics will lead to rapid growth in the number of older people with hearing deficits. Poorer performance in suprathreshold speech understanding and temporal processing with age has been previously linked with progressing inner hair cell (IHC) synaptopathy that precedes age-dependent elevation of auditory thresholds. We compared central sound responsiveness after acoustic trauma in young, middle-aged, and older rats. We demonstrate that IHC synaptopathy progresses from middle age onward and hearing threshold becomes elevated from old age onward. Interestingly, middle-aged animals could centrally compensate for the loss of auditory fiber activity through an increase in late auditory brainstem responses (late auditory brainstem response wave) linked to shortening of central response latencies. In contrast, old animals failed to restore central responsiveness, which correlated with reduced temporal resolution in responding to amplitude changes. These findings may suggest that cochlear IHC synaptopathy with age does not necessarily induce temporal auditory coding deficits, as long as the capacity to generate neuronal gain maintains normal sound-induced central amplitudes

Analysis of Failed Forging Saddling Mandrels and Process Improvements for Increased Mandrel Lifespan

This project seeks to increase the lifespan of steel mandrels used by Schlosser Forge in the saddling process, which is part of the production of forged rings for the aerospace and power generation industries. All saddle mandrel samples were taken from used 4340 steel mandrels. Hardness profiles were measured across rectangular bars cut from the transverse direction of a completely fractured piece of a 7″ diameter mandrel. The hardness near one outer surface of the tested bar was 36 HRC and gradually decreased to 30.5 HRC at the opposite surface. Macroscopic examination of the primary fracture surface along with light microscope imaging of fracture surface feature details suggests that the failure mechanism is likely related to reversed bending fatigue rather than deterioration of the mechanical properties of the steel due to microstructural changes from in-process overtempering during saddling. Cyclic softening of the quenched and tempered steel caused by the saddling process adversely affects the ability of the steel to withstand fatigue. Different heat treatments were conducted to compare the resulting toughness, measured by Charpy impact test, to that of the current process of quenching and tempering the mandrel to a hardness of 38 – 42 HRC. Each heat treatment involved austenitizing at 1500°F for one hour. By varying the tempering temperature, with a constant two hour tempering time, samples were obtained at 28.5 HRC, 39.8 HRC, and 42.5 HRC. Charpy impact energy decreased significantly as hardness increased. An additional heat treatment was conducted where a 4340 steel sample was austenitized, quenched in a 660°F NaNO3-based molten salt bath and held for two hours. The result of this heat treatment is a bainitic structure, which may show improved toughness