Melbourne School of Psychological Sciences - Theses

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    Neuropsychological and computed tomography findings in two subgroups of schizophrenia
    Clausen, Margaretha Helen ( 1986)
    The group of disorders collectively referred to as schizophrenia, have traditionally been conceptualized as functional psychoses in which primary cognitive functions are unimpaired. Despite this, a proportion of schizophrenic patients have long been known to perform poorly on tests of cognitive function and some proceed to an end state resembling organic dementia. The application of CT scans in the last decade to the schizophrenic population, has revealed that some schizophrenic patients have abnormal brain morphology. Changes in brain morphology have also been correlated with cognitive impairment and defect (negative) symptoms. On the basis of these findings two subgroups of schizophrenia have been proposed. Type I schizophrenia is hypothesized to be characterized by normal brain morphology, normal cognition and florid (positive) symptoms. Type II schizophrenia is hypothesized to be characterized by abnormal brain morphology, impaired cognition and predominantly defect (negative) symptoms. Despite the heuristic value of this hypothesis, research was impeded by the lack of valid techniques for the measurement of positive and negative symptoms. Recent reports have provided such measurement scales, however these have not been widely used to specifically investigate CT scan findings and cognitive impairment in schizophrenic patients. This is the report of an investigation which aimed to examine the relationship between positive and negative symptoms, CT scan findings and performance on a wide range of neuropsychological tests known to be sensitive to the effects of localized cerebral disruption in neurological patients 1 in a group of schizophrenic patients. The results suggest that patients with severe negative symptoms have localized cerebral atrophy of the frontal regions of the brain and are impaired on tests of frontal lobe function. These findings support the hypothesis of different subgroups of schizophrenia, in which the underlying aetiology of one subgroup, may be organic in nature.
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    Disturbances in processing inferences in language following right hemisphere brain damage
    McDonald, Skye ( 1982)
    It was argued, that contrary to conventional localisation models attributing all linguistic function to the left hemisphere, the right hemisphere played an important part in the processing of paralinguistic information. Studies of disturbances in prosody; understanding of emotional content in verbal messages; processing of visuospatial aspects of language and processing of pictorial information following right hemisphere damage were reviewed. It was suggested that right hemisphere damaged patients appear to have particular difficulty in drawing inferences from verbal messages, implying an inability to integrate verbal information. It was decided to explore the ability of right hemisphere patients to draw simple inferences from material which was deliberately lacking in emotional content and was designed to contrast the ability to process visuospatial information from non-spatial information. A short memory task was created in which recognition of items which were not heard before but which were semantically continuous with the original story would indicate the integration and storing of the information in the story, rather than its actual lexical representation. A pictorial analogue was also designed to explore pictorial processing. A task matching pictorial alternatives to spoken metaphors was also included since it was suggested the right hemisphere patients were unable to do this task. Three experimental groups were explored; right anterior cortical brain damaged patients; right posterior cortical brain damaged patients, and right subcortical (capsular) and sex was also included. The results indicated that contrary to expectation, the right cortical brain damaged group could process inferences in language both spatial and non-spatial. However, it was found that these patients have a particular problem in rejecting recognition items which did not belong to the original set. This difficulty appeared to be exacerbated when the original material was semantically redundent or involved an understanding of spatial relationships. It was speculated that this may reflect a retrieval rather than memorising difficulty. The performance of the cortical patients on pictorial tasks was found to be more severely disturbed than verbal, and this was considered to be possibly due to a failure to resolve the alternative meanings of the pictures. The cortical patients were also found to prefer literal pictorial alternatives for metaphors, more often than controls. This was also speculated to be due to some failure to appreciate the appropriate meaning of the spoken metaphor, or a difficulty in processing the pictorial information correctly to select a picture depicting the appropriate interpretation. The subcortical (capsular) group performed distinctly differently from the cortical group. It was argued that while these patients also had difficulty rejecting items as not belonging to a cognitive set, they also appeared to be performing in a manner originally expected of the cortical group, i.e. there was suspicion that they were not storing information for meaning but for other more superficial characteristics. These patients performed uniformly regardless of the mode of presentation, pictorial or verbal. They also showed some tendency to select literal meanings of metaphors more often than controls.
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    Individual differences in reading ability
    Cupples, Linda ( 1985)
    The present investigation comprised two experiments that were concerned with individual differences in reading-comprehension ability in relatively skilled adults. Experiment One investigated the relationship that exists between reading-comprehension skill and linguistic awareness when the latter was assessed on three levels - the semantic, the syntactic, and the phonological. It was found that individuals who achieved different levels of comprehension accuracy on a passage-reading test, also performed differently on a task that required them to bring their knowledge about form-class properties of words to conscious awareness. Thus, skilled comprehenders responded more accurately than less skilled comprehenders in a task that required them to judge whether two words served the same grammatical function in sentences. On the other hand, less skilled comprehenders did not perform below the level of skilled comprehenders in two other word-judgement tasks that required them to attend to the meanings or initial sounds of words. Experiment Two was designed to investigate the relationship between reading-comprehension skill and syntactic processes in greater detail. The semantic and syntactic word-judgement tasks from Experiment One were included, as well as two sentence-judgement tasks - meaning and grammaticality classification. Furthermore, in order to determine whether group differences would be observed when individuals did not have to make explicit judgements concerning specific linguistic properties of stimuli, subjects were also required to perform a single-sentence question-answering task. To provide more direct evidence concerning possible differences in the on-line syntactic processes of skilled and less skilled comprehenders, the sentences used in these tasks varied systematically as a function of several different types of syntactic complexity. It was hoped that this would throw some light on any differential increase in processing difficulty that the reader groups experienced as a result of (a) an increase in the number of clauses contained in sentences, (b) a lack of correspondence between the surface order of words and their underlying grammatical roles, and (c) the omission of optional grammatical function words. The results obtained in this experiment replicated those of Experiment One in that skilled comprehenders performed more accurately than less skilled comprehenders in the syntactic but not the semantic word-judgement task. In accordance with this finding, it was also true that reliable ability-related differences were more likely to be detected when individuals were instructed to focus on the grammatical well-formedness of word strings than when they were asked to attend to their meaningfulness. However, group differences were even more pronounced when individuals were required to process single sentences in sufficient detail to answer subsequent comprehension questions. In addition, although no evidence was obtained to suggest that less skilled comprehenders were affected more than skilled comprehenders by increasing the number of clauses contained in sentences, there was some evidence to suggest that skilled comprehenders were better able to cope with increases in syntactic complexity that occur when optional grammatical function words are omitted. However, this ability-related difference was only observed when sentences deviated from the standard S-V-O word order of English, and when the meanings of the individual words that they contained did not constrain the way in which those words could be combined to form a meaningful sequence (i.e., when semantically reversible object relative-clause sentences served as stimuli). On the basis of the findings from both of these experiments, it was concluded that skilled adult comprehenders were better able than less skilled adults to bring their syntactic knowledge to conscious awareness, and also that they were more likely to spontaneously perform a complete syntactic analysis of text whilst reading.
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    Rational emotive education: efficacy with non-clinical children in natural setting: considerations for prevention
    Rosenbaum, Tova ( 1986)
    The present study investigated the efficacy of Rational Emotive Education (REE) in promoting psychological and emotional adjustment of non-clinical primary school children in a natural setting. This study was introduced subsequent to a two-term pilot study conducted in 1983. The sample studied consisted of two intact Grade 4 classes in a private school for girls, randomly assigned to either REE1, REE2, or attention control conditions. Two counsellors were employed, both staff members at the school where the study was conducted. The effects of the intervention program upon the variables of anxiety, locus of control, and rationality were assessed. All students were pre/post/follow-up tested on the Trait scale of the State-Trait Anxiety Inventory (Spielberger, Edwards, Montuori & Lushene, 1973), on the Personal Reaction Survey, Locus of Control for Children (Nowicki & . Strickland, 1931), and the Children's Survey of Rational Beliefs (Knaus, 1974). An additional measure, the Analogue Survey (Bernard & Joyce, 1984) was introduced to evaluate REE’s contribution to adaptive coping. It was hypothesized that subjects in the REE groups will show increase in rational thinking and in application of rational principles to events and situations; that subjects in the REE group will demonstrate reduction in anxiety and ability to respond to situations with moderate emotions and that subjects in the REE groups will become more internal in their locus of control orientation after intervention. It was further hypothesized that REE effectiveness will not be associated with subjects' IQ level, initial level of anxiety, rationality, and locus of control, and therefore be suitable for classroom application. Correlations between gains in rationality and changes in other outcome variables were computed in order to assess whether the gains were the specific mechanisms mediating intervention effects. Counsellor effects on intervention outcome were also assessed. Results indicated that the principles of REE taught in class can be acquired by Grade 4 students, and supported REE's efficacy in increasing subjects' rationality and internality of locus of control. No support was found, however, for REE's efficacy in producing a significant decrease in anxiety compared to the attention control condition. On the Analogue Survey, the REE participants demonstrated better adaptive coping than the subjects in the attention control. Although higher rationality at pre-test was found to be associated with a decrease in anxiety from pre-test to post-test, gains in rationality were found to be associated with an increase in anxiety from pre-test to post-test. No association was revealed between program effectiveness and subjects' IQ level, locus of control, and anxiety at pre-test. Differences in intervention outcome due to counsellor effects were revealed particularly after the six months non-intervention period. Implications of the present study are discussed and future recommendations are made based on study outcome.
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    An algebraic analysis for multiple, social networks
    Pattison, Philippa Eleanor ( 1980)
    Procedures are advanced in the thesis for analysing the semigroup representation of structure in systems of social relations. Such systems may consist of multiple, social networks (Lorrain, 1975; Lorrain and White, 1971) or of blockmodels derived from multirelational network data (Boorman and White, 1976; White, Boorman and Breiger, 1976). The aim of the proposed analysis is to clarify the nature of the representation, as well as to enhance its potential usefulness, by making explicit the relational features upon which it depends. An underlying purpose is therefore also a general evaluative one. (For complete abstract open document.)