Summary: Objectives/Hypothesis: The purpose of this study was to examine the temporal-acoustic differences between trained singers and nonsingers during speech and singing tasks. Methods: Thirty male participants were separated into two groups of 15 according to level of vocal training (ie, trained or untrained). The participants spoke and sang carrier phrases containing English voiced and voiceless bilabial stops, and voice onset time (VOT) was measured for the stop consonant productions. Results: Mixed analyses of variance revealed a significant main effect between speech and singing for /p/ and /b/, with VOT durations longer during speech than singing for /p/, and the opposite true for /b/. Furthermore, a significant phonatory task by vocal training interaction was observed for /p/ productions. Conclusions: The results indicated that the type of phonatory task influences VOT and that these influences are most obvious in trained singers secondary to the articulatory and phonatory adjustments learned during vocal training.

Dynamic Visual Acuity (DVA) in the visual periphery has not been extensively studied. DVA is a measure of an observer's ability to resolve critical details in a target when there is relative motion between the target and the observer. This dissertation examined static and dynamic acuity in the 25-55 deg region of retinal eccentricity under a variety of conditions. Functionally, this region of the visual field is just beyond the "blind spot," but not yet in the "far" visual periphery of 60-90 deg of eccentricity. Traditionally, DVA research has been confined to the assessment of DVA for the foveal (or "central") visual system. However, the peripheral (or "ambient") visual system provides very important information content for the visual and neuro-vestibular systems. This peripheral visual information content is also used to create a sense of ego motion (termed "vection"), and for alerting the visual system to targets entering or leaving the field of view. Past findings involving visual acuity in the peripheral retina have demonstrated that peripheral acuity performance has components related to the notion of "attention" as well. This is particularly true if the peripheral vision research results are to be applied to visually and attentionally complex and/or dynamic real-world environments. In this experiment, the 25-55 deg eccentric region of the retina was tested for DVA in 50 observers. This study used a mixed four-factor research design with Eccentricity (25, 35, 45, 50, 55 deg) as a between-subjects factor. Tracking Difficulty (monitor only, easiest, moderate, most difficult tracking levels), Landolt C Target Velocities (0.0, 4.88, 14.62, and 24.40 deg/s), and Target Direction ("F/R:" fixed or random direction of target appearance) were used as within-subjects factors. A computer presented the Landolt C ring targets under the stated conditions in a random fashion. Acuity was determined for each trial by a modified descending method-of-limits approach with the Landolt C ring target gap widths utilized as the determinant for the acuity measure. The Tracking Task was designated as the primary task, with the secondary task being to indirectly observe the orientation (up, down, right, left) of the Landolt C rings being presented under the various conditions of Target Velocity and Target Direction in the retinal periphery. The resulting Analysis of Variance (ANOVA) revealed significant differences (p < 0.05) for each of the main effects of Eccentricity, Tracking Task Difficulty, Velocity, and Target Direction (F/R). Only two of the two-way interactions were found to be significant (p < 0.05)-- those of Tracking Difficulty x Target Velocity and Target Velocity x Target Direction interactions. The results are discussed in terms of the psychophysical, attention, and "tunnel vision" like models of peripheral visual performance, along with other related human factors literature in the domain of "situation awareness" that are relevant to this general problem area. The results of a separate follow-on mini-study are discussed using a Two-way Contingency Table analysis across all of the treatment conditions when verbal intrusion was embedded in the previously described experimental conditions. This mini-study revealed a significant association (p < 0.05) with not seeing the peripheral targets as accurately when intrusion was present, versus when there was no verbal intrusion. This effect was more pronounced at the highest velocities (14.62 and 24.40 deg/s) as compared with the slower ones (0 and 4.88 deg/s) in terms of the strength of the association, as assessed by a Kappa test statistic. Taken all together, and with consideration given to the relatable scientific literature, these results indicate that the more "busy" a person is with cognitive, visual, or motor-skills tasks, the more likely an individual will show degradation in static or dynamic peripheral visual acuity tasks. Peripheral vision often serves as a "warning" or "status" sensory modality for what is occurring in the local task environment, separate from the foveal visual system. Future research is suggested given the sensitivity of the peripheral visual system to these factors, particularly with regard to how factors involving the notion of attention may affect such "peripheral visual awareness" issues. These issues in turn may play an important role from a human factors and safety perspective in a variety of person-rated vehicular domains. Specific areas that are highlighted for future research in the domain of attention and "peripheral visual awareness" include the low-altitude high-performance flying realm, the flying environment more generally, and in other dynamic multi-task vehicular environments such as that encountered while simultaneously driving and using a car cellular phone. / Ph. D.

Sociality shapes patterns of senescence, evidenced by the remarkable lifespan plasticity of social insect queens and workers. Ants, exemplars of eusociality, provide diverse systems to explore the sociobiology of senescence by examining how sterile workers partition colony labor over their lifespans, and how neurobiological factors affect transitions among social roles and age-related task performance efficacies. Integrating sociobiology, senescence theory, and neurobiology, I examined the relationship of chronological age and social behavior during the ~140-day lifespan of workers of the ant Pheidole dentata. I critically analyzed programmed senescence in respect to the sociobiology of worker longevity and evaluated how large colony size achieved through selection for extended worker lifespan enhances colony fitness. My study found no support for worker programmed senescence. Further testing senescence theory, I determined if workers declined behaviorally as they aged due to increased apoptotic cell death and changes in synaptic complexes associated with higher-order processing in the brain. Using robust behavioral assays I found aging was not correlated with declines in sensory responsiveness or motor functions associated with foraging, nursing, and prey-capture tasks, or activity level and phototaxis. Old minor workers (95 days) followed pheromone trails for greater distances than 20-day old minors and showed higher activity levels, suggesting improvement in behavioral performance. Neural substrates likely underscoring task performance were maintained with age: synaptic complex density was constant and apoptosis was unchanged with age. Sensory and motor control brain regions did not show age-related increases in neurodegeneration. Worker spatial location predicted social role independent of age: foragers exhibited higher activity levels and more aggressive predatory behavior than nurses. Serotonin and dopamine titers increased from 20 to 120 days but showed no clear correlation with social role. Pharmacological manipulations of brain serotonin had no effect on brood care, predatory response, activity, or phototaxis. Finally, I assessed arborization of a serotonergic neuron hypothesized to underscore task performance to determine how aging across subcastes influences neuronal structure. Major workers showed greater branching complexity than minors and an age-related increase in arbor complexity. P. dentata workers appear to show negligible behavioral and neural senescence throughout their lifespans.

The purpose of this study was to investigate the effects of experimenter status and subject dogmatism on anagram solving. The subjects were 90 college students. Only those subjects scoring in the upper or lower thirds on the Dogmatism Scale were utilized. The same experimenter was described as being of either high or low status in each class. In the low status condition, the experimenter was introduced as a student making up an incomplete, while in the high status condition, the experimenter was introduced as a Doctoral student doing research for a Federal Grant Agency. Therefore, four experimental groups were formed in relation to two different levels of dogmatism and two different statuses for the experimenter. A two-way analysis of variance with one covariate {Composite ACT scores to account for intellectual functioning) was computed using subject dogmatism and experimenter status as the independent variables and anagram performance as the dependent variable. It was found that neither the main affects of subject dogmatism and experimenter status, nor the interaction between the two variables were significant. Analysis of a questionnaire designed to evaluate the status manipulation indicated that the manipulation had not been effective. The problem of devising an effective status manipulation for a female experimenter was discussed in relation to future research.

The purpose of this study was to analyze the relationship between attitudes toward the division of household tasks and the amount of time spent accomplishing them by Utah husbands and wives. The sample was 200 husbands and 203 wives residing in Iron, Washington, and Salt Lake Counties . A questionnaire was used to measure the respondents' attitudes toward the division of household labor and two, 24-hour time diaries were used to record time expenditures. Hypotheses regarding traditional and non-traditional attitudes related to the amount of time spent in traditional female t asks, traditional male tasks and time spent in all household tasks were tested. Analysis of variance and Pearson's Product Moment Correlation were used to analyze the data. No statistically significant results were found when husbands' and wives' attitudes toward the allocation of household tasks were related to the amount of time spent in traditional female tasks, traditional male tasks, and total housework It was concluded that attitudes towards the division of household tasks as measured in this research did not predict or influence the amount of time spent accomplishing household tasks.

Developing a computer program is not an easy task. Studies reported that a large number of computer science students decided to change their major due to the extreme challenge in learning programming. Fortunately, studies also reported that learning various self-regulation strategies may help students to continue studying computer science. This study is interested in assessing students’ self-regulation, in specific their task understanding and its revision during programming endeavors. Task understanding is specifically selected because it affects the entire programming endeavor. In this qualitative case study, two female and two male senior computer science students were voluntarily recruited as research participants. They were asked to think aloud while answering five programming problems. Before solving the problem, they had to explain their understanding of the task and after that answer some questions related to their problem-solving process. The participants’ problem-solving process were video and audio-recorded, transcribed, and analyzed. This study found that the participants’ were capable of tailoring their problem-solving approach to the task types, including when understanding the tasks. Given enough time, the participants can understand the problem correctly. When the task is complicated, the participants will gradually update their understanding during the problem-solving endeavor. Some situations may have prevented the participants from understanding the task correctly, including overconfidence, being overwhelmed, utilizing an inappropriate presentation technique, or drawing knowledge from irrelevant experience. Last, the participants tended to be inexperienced in managing unfavorable outcomes.

Escape from instructional demands is one of the most common functions of problem behavior. Some research suggests that a switch from difficult to easy tasks may function as a reinforcer for problem behavior. This is of particular concern for situations in which easy tasks are part of the intervention procedure to reduce problem behavior. This project examined the reinforcing effects of a switch from low-probability (low-p) to high-probability (high-p) tasks for individuals whose problem behavior was maintained by escape from demands. It also provided preliminary evidence as to the quality of reinforcement provided by a switch from low- high-p tasks. Three individuals with disabilities who were referred for treatment of escape-maintained problem behavior participated in this research. We used a multi-element design to compare the effects of two intervention conditions on problem behavior and compliance in relation to control and baseline conditions. During the control condition, no demands were presented, and the participant had continuous access to preferred items and attention. In the baseline condition (break), a break from low-p demands was presented contingent on problem behavior. In the first intervention condition, problem behavior no longer resulted in a break from demands (escape extinction). During the second intervention condition, problem behavior following low-p tasks resulted in a switch to high-p tasks. All participants engaged in elevated levels of problem behavior and decreased compliance when problem behavior resulted in a switch of tasks. These results imply that for individuals whose problem behavior is maintained by escape from demands, a switch from low- to high-p tasks may reinforce problem behavior.

Students who receive special education services in resource classroom settings often engage in low levels of on-task behavior during independent work time. Given the independent work demands in middle school classrooms, it is crucial for students who receive services in a resource classroom to engage in high levels of on-task behavior. The researchers examined the effects of activity schedules on on-task behavior, on-schedule behavior, and percentage of work problems correct in four middle school students receiving special education services in a resource math classroom. Results of the study demonstrate that on-task and on-schedule behavior increased for all participants following the implementation of the activity schedule in both math and language arts classroom settings. Both students and teachers indicated that they liked the intervention and the activity schedule improved on-task behavior. Results of this study extend the use of activity schedules to a novel setting and participant population.

Indiana University-Purdue University Indianapolis (IUPUI) / Deficits in impulse control and decision-making have been implicated in the development and maintenance of alcohol use disorders (AUDs). Individuals with AUD often make disadvantageous choices under conditions of probabilistic risk. The Iowa Gambling Task (IGT) is often used to measure risky decision-making, in which impaired individuals tend to favor large, infrequent rewards even when punished for these choices, rather than smaller, safer, and more advantageous rewards. It remains poorly understood if these deficits are behaviors under genetic control and if ethanol intoxication may alter decision-making. High and Low Alcohol Preferring (HAP3 and LAP3, respectively) mice were trained on a novel gambling task to investigate these possible influences. In Experiment 1, HAP3s and LAP3s responded for a 0.1% saccharin solution, choosing between a risky and a safe option. Importantly, choosing the risky option was meant to be ultimately disadvantageous. In Experiment 2, these same HAP3 mice responded for saccharin or saccharin plus 10% ethanol. Contrary to hypothesis, LAP3s preferred the risky option more than HAP3s. Alcohol increased preference for the risky lever, but only in male mice. HAP3 preference for the safe lever may be explained by higher motivation to obtain sweet rewards, or higher overall avidity for responding. Ethanol-induced changes in male risk behavior may be explained by higher androgen levels, but further investigation is required. Similarly, continued research is necessary to optimize a risky decision-making task for both lines, and thus investigate possible genetic differences in risk acceptance that correlate with differences in alcohol intake.

京都大学 / 0048 / 新制・課程博士 / 博士(人間健康科学) / 甲第19179号 / 人健博第27号 / 新制||人健||3(附属図書館) / 32171 / 京都大学大学院医学研究科人間健康科学系専攻 / (主査)教授 三谷 章, 教授 村井 俊哉, 教授 精山 明敏 / 学位規則第4条第1項該当 / Doctor of Human Health Sciences / Kyoto University / DFAM