No description available.

No description available.

The present study was motivated by a need to employ multilevel studies to better understand why the experience of stressful life events is predictive of increased rates of psychopathology. Specifically, this study aimed to test the moderating role of coping on associations between stress reactivity (autonomic arousal) and broad-spectrum internalizing and externalizing problems in a normative sample. Participants were 140 adolescents and emerging adults (ages 14-30 years; 60% female) who completed questionnaires on coping, stressful life events, personality, and behavioral/emotional problems. Skin conductance and heart rate data were also measured while participants completed two laboratory stress tasks: a public speaking task and a task involving serial subtraction. Path analytic results suggested negative main effects for primary and secondary control coping, and positive main effects for disengagement coping, on internalizing and externalizing problems. Evidence was also found for interactive effects of skin conductance reactivity to the public speaking task and secondary control coping on externalizing problems for adolescents only, such that there was a negative association between SCL reactivity and externalizing problems for individuals reporting low use of secondary control coping, but SCL reactivity and externalizing problems were unrelated for individuals reporting high use of secondary control coping. Associations were also found between personality variables and both coping and internalizing and externalizing problems, but not with autonomic arousal. Although a priori hypotheses regarding interaction effects were mainly unsupported, results from the present study suggest that future research examining the interplay among stress reactivity, coping, and personality will be important in furthering our understanding of the development of psychopathology and helping to tailor effective efforts at prevention and intervention.

No description available.

Thesis (Ed.D.)--Boston University

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Purpose: To better understand the relative contributions of rod, cone, and melanopsin to the human pupillary light reflex (PLR) and to determine the optimal conditions for assessing the health of the rod, cone, and melanopsin pathways with a relatively brief clinical protocol using the PLR. Methods: The PLR was measured with an eye tracker and stimuli controlled with a Ganzfeld system. Exp.1: 2.5-log cd/m^2 red (640±10nm) and blue (467±17nm) stimuli of various durations were presented after dark-adaptation. Exp. 2 and 3: 1-sec red and blue stimuli were presented at different intensity levels in the dark (Exp.2) or on a 0.78-log cd/m^2 blue background (Exp.3). Based on the results of Exp. 1-3, a clinical protocol was designed and tested on healthy controls (Exp. 4) and patients (Exp. 5) with retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), and achmatopsia (ACHM). Results: The optimal duration for producing the melanopsin-driven sustained pupil response following termination of an intense blue stimulus was 1 sec. PLR rod- and melanopsin-driven components are best studied with low and high intensity flashes, respectively, presented in the dark (Exp. 2). A blue background suppressed rod and melanopsin responses, making it easy to assess the cone contribution with a red flash (Exp. 3). The proposed clinical protocol successfully provided reliable data from 8 normal subjects (Exp. 4). With the clinical protocol, robust melanopsin responses could be seen in the all patients with little or no contribution from the rods and cones (Exp. 5). Conclusions: It is possible to identify the rod, cone, and melanopsin contributions to the PLR with blue flashes at 2 or 3 intensity levels in dark and one red flash on a blue background.

The studies contained in this dissertation were driven by a desire to improve the methods for sensory testing of cough for clinical research and practice. Two scientific gaps in the cough evaluation literature were identified and investigated using two specific studies on healthy young adult participants. The first study focused on validating an appropriate descriptor for cough sensations (Chapter 2) and the second study (Chapter 3) focused on evaluating magnitude estimation tools to measure cough sensations. The findings of this dissertation make several unique contributions to the cough literature. The first study systematically compared two descriptive responses to cough stimuli (i.e., capsaicin) within subjects in terms of both cough sensory and cough motor outcomes. Findings revealed two types of descriptive responses for capsaicin stimuli, warm/burn and urge-to-cough (UTC). The UTC descriptor was, however, more sensitive and a valid predictor of cough response. The second study systematically compared two magnitude estimation tools, the Modified Borg Scale (MBS) and the generalized Labeled Magnitude Scale (gLMS) to measure the UTC sensations. Findings revealed that both tools were reliable and valid in detecting UTC sensations and predicting cough response. However, a differential effect to detection of UTC sensations across neighboring stimuli concentrations were demonstrated by the two tools. This dissertation provides the first set of normative reference values for UTC responses across a wide range of sensory continua using the conventional metric, the MBS, and an additional metric, the gLMS. Limitations are acknowledged and future work is suggested.

Thesis presented for the degree of Doctor of Medicine at the University of the Witwatersrand, Johannesburg. / WHSLYP2017