published_or_final_version / Nursing Studies / Master / Master of Nursing

This dissertation reports on a study conducted to examine the morphological, behavioral, and environmental sources of variation in the structure of house cricket, Acheta domesticus, calling song. Song variations may be important in female mating decisions and influence male mating success. Eleven song parameters were measured: chirp duration, interchirp duration, syllable number, syllable duration, intersyllable duration, mean frequency, frequency intensity, minimum frequency, maximum frequency, syllable intensity, and intensity difference between syllable and frequency intensity. Morphological factors examined included body: mass, length, color, asymmetry, intactness; and male age. Behavioral factors were timing of song bouts and proclivity to sing. Environmental conditions of high population densities were simulated by temporarily placing males into an arena with three other males. The calling song structure of tactilely isolated males resulted in three factors: frequency (mean, minimum, and maximum frequencies); intensity (syllable intensity, and intensity difference); and variability (difference between syllable intensity and frequency intensity). Males with high body intactness sang at lower frequencies. Asymmetrical males sang more intense songs. Large males sang with more intensity and frequency variability. Intermale competitions resulted in distinguishable linear dominance hierarchies. Lower-ranking males sang less often than higher-ranking males, altered singing times, and sang quieter songs. Intermale competition resulted in males altering song structure. Analysis of post-competitive songs resulted in three factors: frequency (mean and maximum frequencies, and intensity difference); energy (duty-cycle, intensity, and minimum frequency) and variability (unchanged). Higher-ranking asymmetrical males sang at lower frequencies. Higher-ranking males sang with greater energy, and timed their singing to female receptive times. Higher-ranking, large, intact males sang with less variability. This study indicated that A. domesticus males signal phenotypic information via their calling song characteristics. More specifically, in low population densities males signal information concerning their fitness-related qualities. After having established dominance orders, the male signal information concerning their rank in conjunction with fitness. The implications of this study were that intermale competition altered the song cues available to the females and may alter female mating decisions.

This study was an investigation of early changes in long latency event-related potentials with an emphasis on the N200/P300 complex in a group of adults with mild traumatic brain injury (TBI). Subjects with mild TBI and a matched group of non-injured subjects were presented three auditory oddball tasks differing in degree of difficulty. Subjects with TBI were tested within 100 hours of the injury and again at 20 days post-injury. Non-injured subjects also underwent two test sessions, with visit two occurring 18 days after visit one. Event-related potentials were recorded from three midline sites (Fz, Cz, Pz) during the three oddball tasks, two tone-frequency discrimination tasks and one tone-duration discrimination task. The amplitude and latency of both the N200 and the P300 were compared between the two groups. The amplitudes of the two components did not differ significantly between the two groups. However, the latencies of both the N200 and the P300 were prolonged in the mild TBI group. This delay interacted significantly with recording site, with the maximal between-group difference occurring at Fz for both components. The group effect did not interact significantly with the timing of the test session or the difficulty of the oddball task. Taking the latencies of the two components as indices of information processing speed, the data suggest the presence of reduced processing speed in the mild TBI group that persists for at least three weeks post-injury. Increasing task difficulty, at least to the level used in the present study, did not enhance the observed difference between the two groups. The findings related to recording site are consistent with neurobehavioral, neuroimaging, and pathophysiological data which indicate greater effects of injury on frontal regions of the brain.

This study examined whether an intervention program based on a neuropsychological approach to specific reading disability subtypes would improve overall reading ability, Subjects were middle school righthanded boys and girls who were low achieving readers. The readers were initially subtyped according to Bakker's clinical-inferential approach used with clinic children and classified as L-type dyslexic (substantive errors and excessively fast reading), P-type dyslexic (slow and laborious reading), or M-type dyslexic (a combination of both L-type and P-type dyslexia). The method of assessment was used as a pre-posttest group design. The dependent variables included a reading decoding measure, oral reading errors, and comprehension scores from the Multilevel Academic Skills Inventory (MASI), which is a reading and language battery. All three groups were receiving additional reading instruction from their school reading program. Experimental treatment occurred in two parts: Hemispheric Specific Stimulation (HSS) and Hemispheric Alluding Stimuli (HAS). When the study was concluded, a fused dichotic listening task was administered once to discern a potential relationship between the subtypes of the groups and their particular hemispheric processing capacity for language. The results revealed that the neuropsychological treatment was effective at improving reading comprehension and accuracy. Although there were perceived benefits in comprehension, no direct comprehension exercises were used in this study so the gains could have been attributed to the school reading program. There were no changes in word recognition between the pretest and the posttest. The results from the fused dichotic words task were not significant.

Spatial memory tasks known to be sensitive to hippocampal lesions in the rat were adapted to humans. These tasks and others known to be sensitive to medial temporal lesions in the human, were administered in order to investigate the effects of selective damage to medial temporal lobe structures of the human brain. The patients had undergone thermo-coagulation with a single electrode along the amygdalo-hippocampal axis in an attempt to alleviate their epilepsy. With this surgical technique, lesions to single medial temporal lobe structures can be carried out. The locations of the lesions were assessed by means of digital high-resolution magnetic resonance imaging and software allowing a 3-D reconstruction of the brain. A break in the collateral sulcus, dividing it into the anterior collateral sulcus and the posterior collateral sulcus is reported for the first time. This division corresponds to the posterior border of the entorhinal/perirhinal cortex and the anterior border of the parahippocampal cortex, and therefore helped in the identification of the areas. The results confirmed the role of the right hippocampus in visuo-spatial memory tasks (object location, Rey-Osterrieth Figure with and without delay), and the left for verbal memory tasks (Rey Auditory Verbal Learning Task with delay). Patients with lesions to the right parahippocampal cortex were also impaired on a spatial oddball task, but not on the object equivalent. Surprisingly, patients with lesions either to the right or to the left hippocampus were unimpaired on several memory tasks, including a spatial one, with a 30 minute delay, designed to be analogous to the Morris water maze. Patients with lesions to the right parahippocampal cortex were impaired on this task with a 30 minute delay, suggesting that the parahippocampal cortex itself may play an important role in spatial memory.

Two studies examined the electrophysiology of cognitive functioning in Alzheimer's disease. In the first study, fifteen AD patients and 26 elderly controls engaged in a lexical decision task with a list of words and non-words while event-related brain potentials were recorded. Embedded in the list were two repetition conditions: one where words were repeated at relatively long lags and one where words were repeated shortly after a brief masked presentation. Although elderly controls displayed behavioral and ERP repetition priming for words repeated at long lags, AD patients did not. In contrast, both controls and AD patients displayed an ERP repetition priming effect for the words repeated shortly after a brief masked presentation. Although the 2 ERP priming effects differ in elderly controls, the masked priming effect was also different between controls and AD patients. The results are used to critically assess the utility of an impaired/intact dichotomy when examining memory performance in brain damaged populations and are interpreted as lending support to dimensional models which postulate complex interactions between brain regions. In the second study utilizing the participants from the first study, eighteen AD patients and 22 elderly controls had their EEG recorded under four conditions: eyes open and closed resting baseline, and a verbal and spatial categorization task. EEG power was examined in 6 spectral bands revealing significant differences in the Theta band across all conditions and in the Alpha band during resting eyes closed and the categorization tasks. Alpha activity was examined utilizing instantaneous frequency analysis (IFA) in order to produce a measure of amplitude per unit time in the eyes open baseline and for the verbal and spatial cognitive tasks. The IFA analysis revealed that AD patients, relative to controls, failed to show an event-related decrease in alpha activity across the entire scalp during the performance of the 2 cognitive tasks. The failure of AD patients to display the expected alpha decrease in the left frontal region was significantly correlated with verbal task performance. These results are discussed with respect to disruptions in sustained and focused attentional mechanisms which appear to occur in AD.

In this thesis, computer integration technology and human interfaces will be assessed to determine if it can help in sharing, connecting, and transferring information in Landscape Architecture. Traditional methods of integration using manual techniques need to be modified for computer applications. Existing user friendly computer integration technology was researched and an experimental demonstration based on the Landscape Architectural applications was developed. Other applications and benefit of computer integration technology in Landscape Architectural practice are discussed.

The purpose of this study was to explore the lived experience of smokers hospitalized on a tobacco free psychiatric unit through the research methodology of phenomenology. The sample consisted of 3 participants: a 44 year old Caucasian female, a 36 year old Caucasian male, and a 38 year old Caucasian female. Interviews were audiotaped and analyzed using an adaptation of Colaizzi's eight-step procedure. Results included these Theme Categories: The Psychological Experience of Smoking Abstinence; The Physiological Experience of Smoking Abstinence; The Socio-Cultural Experience of Smoking and Its Abstinence; Spiritual Aspects of Smoking; How Do I Deal with Smoking Abstinence?; What about Smoking Cessation?; and Persisting Perceptions of a Tobacco Free Psychiatric Hospitalization. The essential structure of the lived experience of smokers hospitalized on a tobacco free psychiatric unit was formulated from the data.

The aim of this study was to investigate the hypothesis that pre-therapeutic "dispositional optimism" is associated with post-therapeutic "quality of life (QOL)" in a sample of patients with upper aerodigestive tract (UADT) cancer. A sample of 101 subjects with UADT cancer was enrolled in this cohort study. QOL was evaluated through the EORTC QLQ-H&N35 and the global domain of the EORTC QLQ C-30. Dispositional optimism was measured using the Life Orientation Test (LOT). Subjects completed these self-administered questionnaires prior to treatment and one week to one month after their treatment. Other data were gathered by interview and medical chart review. / Prior to treatment, an association between dispositional optimism and QOL was observed for the global, pain, swallowing, senses and feeling ill domains. However, no such associations were observed following treatment.

<p> Depression and abnormal salivary cortisol levels have been related to poor health outcomes for both mothers and their children. However, few studies have examined whether protective factors, such as optimism, resilience, or coping styles are associated with depression and cortisol during pregnancy. The current study examined whether these protective factors were associated with depressive symptomology (current and lifetime depression) and salivary cortisol patterns among 100 low-income pregnant women. Hierarchical regression analyses found that: (a) greater levels of optimism and resilience were associated with lower levels of depression (<i>R²</i> = .17 to .46, <i>p</i> &lt; .05); (b) women low in resilience reported more depressive symptoms when using more positive reinterpretation coping (<i>R²</i> = .36, <i>p</i> &lt; .05); and (c) women high in resilience reported more depressive symptoms when using more avoidance coping (<i>R²</i> = .20, <i> p</i> &lt; .05). Results suggest that coping processes may be important in understanding the mental and physical experience of depression.</p>