Includes list of articles published or accepted for publication during the period of PhD candidature. / "July, 2004" / Includes bibliographical references (leaves 255-293) / xxviii, 293 leaves : ill., plates (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Pathology, 2004?

<p>Studiens syfte var att med neuropsykologiska utredningsverktyg undersöka exekutiva funktioner hos allsvenska fotbollsspelare samt division 1 spelare. Även sambandet mellan spelarnas exekutiva funktioner, gjorda mål och assist undersöktes. 57 herr- och damspelare testades. Elva kliniska utredningstest användes. Resultaten visade att de allsvenska spelarna hade signifikant bättre kapacitet på vissa exekutiva funktioner än spelarna från division 1. Även de spelare som gjort flest mål och assist hade i förhållande till de som gjort minst, bättre kapacitet på flertalet exekutiva funktioner. Den förklarade variansen visade att de exekutiva funktionerna, i vissa fall, utgjorde mellan 30 % och 40 % av samtliga egenskaper som påverkar spelarnas prestationsförmåga mätt i mål och assist. Resultaten indikerar att kapaciteten av de exekutiva funktionera kan ha betydelse för fotbollspelares sportsliga framgång.</p> / <p>The purpose of this study was to, with neuropsychological test tools, examine the executive functions among soccer players from premier league and first division. The relations between the players’ executive functions and their goals and assists were also examined. 57 male and female soccer players were tested. Eleven different clinical test tools were used. The result shows that the players from premier league had significant better capacity of their executive functions than the players from the first division. Also the players who scored most goals and did most assist had better capacity in several of their executive functions than the players that scored and assisted least. R Square showed in some cases that 30 to 40 % of the total capacity of the players’ performance in assists and goal scoring were provided by the executive functions. The result indicates that the capacity of the executive functions among soccer players could have importance for their success.</p>

Apathy is a debilitating non-motor symptom in Parkinson’s disease (PD) that is closely associated with cognitive dysfunction, depression, and caregiver burden. The proposed etiology and operational definition of apathy involves a tripartite model that includes cognitive, behavioral, and emotional manifestations. This theoretical model has not been statistically validated. We examined the tripartite structure of apathy in PD, and subsequent associations between apathy factors and demographic, disease, and neuropsychological measures. One hundred forty-one patients with idiopathic PD underwent neurological examination and comprehensive neuropsychological testing including the Apathy Evaluation Scale (AES). Statistical analyses included correlation, means comparison, item analysis, and confirmatory factor analysis using SEM. The AES was found to be a valid and reliable measure of apathy. Although a tripartite model of apathy was not supported, a novel 3-factor structure of apathy (R-Apathy) emerged characterized by Cognitive/Emotional and Behavioral factors. Both education and depression were significantly associated with R-Apathy. When these were controlled, R-Apathy was associated with impairment in select executive function and visuospatial skills. Apathy remains an important dimension in understanding nonmotor changes in PD. As a whole, apathy correlated with specific areas of neuropsychological dysfunction apart from the influence of depression. Manifestations of apathy such as mental disengagement and behavioral withdrawal are key features of the disease presentation. The importance of evaluating apathy as a contributing factor to patients’ neurocognitive status, mood, and psychosocial functioning should not be underestimated. Furthermore, an apathy evaluation should be included as a standard part of a Parkinson’s evaluation.

Despite very extensive studies on molecular mechanisms of learning and memory formation it is little known about individual variation in the learning skills within a random animal population and about the differences in the brain biochemistry behind this variation. In the present study, we have focused on the expression and distribution of nitric oxide synthase (NOS), one of the molecules implemented in activity-dependent neuroplasticity, in the rat hippocampus, the structure critical for episodic memory in humans and animals. The aim of the present study was to investigate the differences in expression of three different NOS isoforms: neural (n), epithelial (e), and inducible (i), in four hippocampal subregions (CA1, CA3, DG, and hilus) between Wistar rats classified on the basis of their performance in partially baited 12-arm radial maze as &ldquo / good&rdquo / and &ldquo / poor&rdquo / learners. The NOS isoforms were visualized on coronal hippocampal sections using fluorescent immunohistochemistry technique and n- and eNOS images were processed using ImageJ software, while iNOS immunoreactivity (IR) was assessed by counting immunoreactive cells. In this study, overall hippocampal levels of nNOS were significantly higher than those of eNOS and iNOS. The level of n and eNOS was higher in CA1 compared to DG/hilus areas, but lower than that in CA3 region. The expression of iNOS was the highest in CA1 and the lowest in hilus region. nNOS IR was significantly higher in &ldquo / poor&rdquo / than in &ldquo / good&rdquo / learners but only in CA1 region. No significant between-group differences were found in eNOS expression. iNOS expression was higher in &ldquo / poor&rdquo / learners but it did not reach the required significance level.

Chronic neck pain, a common cause of disability, seems to be the result of several interacting mechanisms. In addition to degenerative and inflammatory changes and trauma, psychological and psychosocial factors are also involved. One common type of trauma associated with chronic neck pain is whiplash injury; this sometimes results in whiplash-associated disorder (WAD), a controversial condition with largely unknown pathogenetic mechanisms. We studied the prevalence of chronic neck pain of traumatic and non-traumatic origin and compared the prevalence of, sociodemographic data, self-perceived health, workload and chronic lowback pain in these groups. In a ready-made questionnaire (MONICA study), we added questions about cervical spine and low-back complaints. 6,000 (72%) completed a self-administered questionnaire. 43% reported neck pain: 48% of women and 38% of men. Women of working age had more neck pain than retired women, a phenomenon not seen in men. 19% of the studied population suffered from chronic neck pain and it was more frequent in women. A history of neck trauma was common in those with chronic neck pain. Those with a history of neck trauma perceived their health worse and were more often on sick-leave. About 50% of those with traumatic and non-traumatic chronic neck pain also had chronic low-back pain. We assessed the subjective and objective neuropsychological functioning in 42 patients with chronic neck pain, 21 with a whiplash trauma, and 21 without previous neck trauma. Despite cognitive complaints, the WAD patients had normal neuropsychological functioning, but the WAD group especially had deviant MMPI results—indicating impaired coping ability and somatization.WAD patients had no alterations in cerebral blood-flow pattern, as measured by rCBF-SPECT and SPM analysis, compared to healthy controls. This contrasts with the non-traumatic group with chronic neck pain, which showed marked blood-flow changes. The blood-flow changes in the non-traumatic group were similar to those described earlier in pain patients but— remarkably enough—were different from those in the WAD group. Chronic neck pain of whiplash and non-traumatic origin appears to be unique in some respects. A better understanding of the underlying pathological mechanisms is a prerequisite for prevention of the development of such chronic pain syndromes and for improvement of the treatment of patients with severe symptoms.

Studiens syfte var att med neuropsykologiska utredningsverktyg undersöka exekutiva funktioner hos allsvenska fotbollsspelare samt division 1 spelare. Även sambandet mellan spelarnas exekutiva funktioner, gjorda mål och assist undersöktes. 57 herr- och damspelare testades. Elva kliniska utredningstest användes. Resultaten visade att de allsvenska spelarna hade signifikant bättre kapacitet på vissa exekutiva funktioner än spelarna från division 1. Även de spelare som gjort flest mål och assist hade i förhållande till de som gjort minst, bättre kapacitet på flertalet exekutiva funktioner. Den förklarade variansen visade att de exekutiva funktionerna, i vissa fall, utgjorde mellan 30 % och 40 % av samtliga egenskaper som påverkar spelarnas prestationsförmåga mätt i mål och assist. Resultaten indikerar att kapaciteten av de exekutiva funktionera kan ha betydelse för fotbollspelares sportsliga framgång. / The purpose of this study was to, with neuropsychological test tools, examine the executive functions among soccer players from premier league and first division. The relations between the players’ executive functions and their goals and assists were also examined. 57 male and female soccer players were tested. Eleven different clinical test tools were used. The result shows that the players from premier league had significant better capacity of their executive functions than the players from the first division. Also the players who scored most goals and did most assist had better capacity in several of their executive functions than the players that scored and assisted least. R Square showed in some cases that 30 to 40 % of the total capacity of the players’ performance in assists and goal scoring were provided by the executive functions. The result indicates that the capacity of the executive functions among soccer players could have importance for their success.

Working memory is a mental system that is related to cognitive control and higher cognition. Although the topic of working memory is well researched, there is a great deal of debate about the mechanisms that drive individual differences in working memory capacity. Moreover, little is known about the direct relationships between different types of working memory tasks. The present study uses structural equation modeling to examine three varieties of working memory task: The complex span, running memory span, and visual arrays. It is found that, while complex and running span performance is directly predicted by immediate memory and retrieval from long-term memory, visual arrays is directly predicted by attention control. Despite these differences, all tasks are found to be united by executive attention, which is conceptualized as an executive process that is apparent across several types of attention and memory task. A second analysis examines the relationship between working memory and general fluid intelligence. It is concluded that, while executive attention accounts for the largest portion of the correlation between working memory and fluid intelligence, immediate memory and retrieval from long term memory are also critical to explaining this relationship.

This body of research investigates the effects of sex and estrogen on higher brain functions, in general, and on working memory, in particular. A female advantage for object-location and verbal working memory has been reported, and estrogen supplementation facilitates performance of the same. Less is known about whether the female advantage is due to the verbalizability of the stimuli, and whether estrogen-suppression adversely affects performance on working memory and other neuropsychological domains sensitive to estrogen. Study 1 examined sex-related differences in young adults on an object-location working memory measure that varied in verbalizability of stimuli and task presentation (i.e., manual or computer); as expected, females performed better than males regardless of the verbalizability of the stimuli or task presentation. Study 2 examined sex-related differences in young adults on the n-back working memory task across verbal, spatial, and object conditions. Contrary to the hypotheses, there was no sex effect for the verbal version of the n-back task, and males actually performed better than females on the object version; as expected, males performed better than females on the spatial version. Study 3 investigated the effect of estrogen suppression in middle-aged and older adult females undergoing treatment for estrogenic breast cancer using the experimental working memory measures from Studies 1 and 2, and a comprehensive neuropsychological battery that included measures considered to be either sensitive (e.g., letter fluency) or insensitive (e.g., spatial ability) to the female advantage and the effects of estrogen. The estrogen suppression group performed more poorly than healthy age-matched controls on certain estrogen-sensitive measures (i.e., speeded visuomotor attention, speeded manual dexterity, and letter fluency), but unexpectedly, the groups did not differ on any of the memory measures presumed to be estrogen-sensitive. This body of research suggests that although certain working memory measures are sensitive to sex effects, the direction depends on the domain, and that estrogen suppression does not impact working memory in postmenopausal women but does adversely impact speeded performance measures.

Knowledge of the literature pertaining to patterns of performance in normal individuals is essential if we are to understand intraindividual variability in neurocognitive test performance in neuropsychiatric disorders. Twenty-five healthy individuals with a high-level of education were evaluated on a short neuropsychological battery which spanned several cognitive domains. ---Results indicated that cognitive abilities are not equally distributed within a sample of healthy, high-level functioning individuals. This may be of interest to neuropsychologists who might base clinical inference about the presence of cerebral dysfunction, at least in part, on marked variation in a patient’s level of cognitive test performance. The practice of deductive reasoning in clinical neuropsychology may be prone to false-positive conclusions about cognitive functioning in neuropsychiatric disorders where base-rates of cognitive impairments are low and pre-existing educational achievements are high.

While neuropsychological deficits have been reported in healthy individuals who use cannabis, data in patients with multiple sclerosis (MS) are lacking. Given that MS is associated with cognitive deterioration, the aim of this study was to determine the cognitive effects of inhaled or ingested cannabis in this population. Fifty MS patients (25 cannabis users and 25 non-users) completed the Minimal Assessment of Cognitive Function in MS battery of neuropsychological tests. Cannabis users had significantly poorer performance on measures of information processing speed, executive functions, and visuospatial perception, and were twice as likely to be classified as globally cognitively impaired. Similar results were found after controlling for potential confounding variables. This study provides evidence that prolonged cannabis use in MS patients is associated with poorer performance on cognitive domains commonly affected in this population. The therapeutic benefits patients may derive from using cannabis should be weighed against the associated cognitive side-effects.