Melbourne School of Psychological Sciences - Theses
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ItemThe hyper-ordinary depression hypothesis, and mechanisms of cognitive rigidity in depression (or zen and art of reducing depressive cycle maintenance)( 2017)This thesis is comprised of two related parts: a theoretical inquiry into the antidepressant mechanisms of a range of Non-ordinary States of Consciousness (NSCs), alongside the development of a novel mechanistic account of depression; and a set of four empirical studies that investigated aspects of cognitive rigidity in depression that relate to this novel account. In Chapter 1, I show that various disparate induction procedures (e.g., mindfulness practice, psychedelics, brain entrainment, and endurance exercise) are associated with both the production of NSCs and the reduction of depressive symptoms. Interestingly, these NSCs have in common many core neurological, psychological, and phenomenological features that are antithetical to core features of depression. I suggest that these features of NSCs represent potential therapeutic mechanisms, and that the production of certain NSCs mediates the reduction in depressive symptoms. I argue that two related superordinate features underlie these changes – enhanced Receptivity (e.g., perceptual, particular, absorbed, suggestible, flexible, open) and enhanced Projectivity (e.g., self-efficacious, intimate, relational, self-transcendent), that together represent elevated Interdependence between the individual and the world. In contrast, I argue that numerous features of depression appear to represent a fundamental deficiency in Interdependent processing, and that this deficiency extends into the most basic level of minimal subjectivity, representing a global qualitative change that satisfies criteria for an altered state of consciousness. Consequently, I argue that depression is associated with a ‘Hyper-ordinary’ state of consciousness. I suggest that the degree to which an NSC can reduce depression is a function of the degree to which Interdependent processing occurs within the state, and endures thereafter. Chapters 2, 3, and 4 report on a set of four empirical studies that investigated cognitive abnormalities in depression associated with the Receptivity aspect of the Hyper-ordinary account of depression. These tasks explored the link between depressive symptoms and three related processes that fall under the rubric of ‘cognitive flexibility’ – the ability for unexpected information to gain access to awareness; the ability to generate divergent representations for that information; and the ability to abandon extant representations in favour of those that are more compatible with unexpected information. As depression is associated with various forms of cognitive rigidity, including biased beliefs and interpretations that resist change, these studies investigated processing abnormalities in depression that might account for such rigidities. Additionally, as cognitive rigidity in depression is typically confined to specific forms of information processing, the tasks all employed stimuli that are highly relevant to the level of construal, the thematic content, and the rhetorical mode of depressotypic thinking, thereby increasing their sensitivity to detect differences, and their ability to reveal potential therapeutic targets. Results showed that depressive symptoms were related to slower access to awareness for unexpected positive information (Chapter 4), deficits in producing diverse categories of response, with no relation to the total number of responses generated (Chapter 3), and deficits in updating interpretations, regardless of whether updating resulted in a more positive or negative interpretation (Chapter 2). Together, this thesis offers a novel account of the depression experience, argues for a set of plausible therapeutic candidates for the antidepressant effects of certain NSCs, and reports on three novel tasks that probe ecologically relevant features of cognitive rigidity in depression, thereby revealing novel therapeutic targets. The picture of depression that emerges from the theoretical account is of a profoundly isolated state characterised by a fundamental deficit in the individual’s susceptibility to be affected by their context, and the perception that one’s context cannot be affected by the individual. The empirical studies show how this deficiency relates to the diminished influence of contextual factors over interpretations and expectations in depression. The hope is that this work can improve and extend the current understanding of depression and its causes, and lead to new methods of recovery.
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ItemVisual perceptual assimilation of non-native speech( 2017)Studies of auditory speech perception show that native language exerts a powerful influence on the perception of a second language. This influence is manifested in the assimilation of non-native sounds into native speech categories. However, speech is a multimodal experience, incorporating visual aspects of speech as well as sounds. The novel question addressed here is whether these aspects are assimilated naturally in the audio-visual (AV) perception of speech. The main hypothesis is that the visual aspects of non-native speech are assimilated into native categories, leading to the prediction that visual aspects of non-native speech that are dissimilar to the native language will be identified more readily than visual aspects of non-native speech that are similar to the native language. In several experiments, English-speaking participants were presented with native and non-native vowels and syllables that were experimentally validated and ranked according to their similarity to the native (English) language. Surprisingly, the results showed no evidence of visual perceptual assimilation for similar or dissimilar visual features of non-native speech. The study also investigated perception of visual aspects of non-native speech at the lexical level of cognate words and sentences compared to visual aspects of the native language. The results showed that participants were unable to discriminate native and non-native languages based on visual-only input. When native and non-native sentences were temporally reversed, participants were unable to discriminate veridical from temporally-reversed sentences in a visual-only mode condition. Furthermore, in cross-modal matching experiments, participants were unable to translate a visual image into the corresponding auditory signal, unless a written cue was provided or an auditory signal was present. Moreover, slowing the presentation of stimuli during AV speech perception did not facilitate processing of the visual aspects of non-native speech. Overall, the current study found a remarkably limited influence from the visual-only aspects of speech on non-native perception when compared to auditory-only input but did show for the first time that participants were more likely to falsely accept non-native stimuli as native in the multi-modal AV condition when compared to the auditory-only and visual-only conditions. The results therefore extend prior reports about the influence of visual aspects of speech on perception of sounds in a non-native language. These findings are discussed in terms of models of non-native speech perception and of applicability for teaching non-native languages to second language learners.
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ItemThe effect of acupuncture on upper airway function and physiology in obstructive sleep apnoea( 2017)Obstructive sleep apnoea (OSA) involves repetitive obstruction of the upper airway during sleep. Continuous positive airway pressure (CPAP) is the most common treatment, however, many patients cannot tolerate CPAP and adherence rates are low. Recent research has suggested that acupuncture can reduce the severity of OSA. The past research, while promising did not conform to normal Chinese medicine (CM) practice as the researchers failed to diagnose CM syndromes in their patient sample nor design their treatment based on CM syndrome analysis. It was also not possible to rule out potential confounding effects of the sham treatment, as the method employed was not guaranteed to be biologically inert. The aim of the present study was to address these limitations and determine whether acupuncture is an effective alternative treatment for OSA, and to identify underlying physiological changes as a result of acupuncture treatment. Initially, 39 patients admitted for investigative PSG to diagnose OSA underwent standard CM diagnostic procedures to identify common CM syndromes in the OSA population. Four CM phenotypes of OSA were identified and the most common phenotype (occurring in >44% of the sampled population) was then incorporated into the inclusion criteria for the clinical trial of acupuncture treatment. The acupuncture treatment employed was also designed to target the CM phenotype pathology. Further, the sham method employed in the present study, was also guaranteed to be biologically inert. Twenty OSA patients were randomly assigned to receive either 12 weeks of active needle acupuncture (n=10 (3 F); mean age=56.3 years) or sham laser acupuncture (n=10 (3 F); mean age=45.3 years) treatments. Prior to and following the treatment period subjects underwent detailed polysomnography, including measurement of epiglottic pressure, calibrated airflow and genioglossus muscle activity. In addition, subjective health and wellbeing, sleepiness and mood were assessed. AHI, waking nasopharyngeal resistance, ventilation, arousal threshold and genioglossus muscle activity were analysed while blinded to treatment type and study time. One participant was excluded due to an insufficient amount of sleep for analysis. There was no significant effect of treatment type on pre- and post-treatment measurement of NREM AHI (mean pre-treatment: active= 38.10, sham=26.44; mean post-treatment: active=38.83; sham=37.06 events/hour) or NREM AI (mean pre-treatment: active=57.71, sham=49.03; mean post-treatment: active=58.98, sham=58.60 events/hour). There were no significant differences within the active or sham groups, nor between groups across time for the subjective questionnaires. All upper airway physiology measurements made during NREM sleep were also unchanged following both sham and active acupuncture treatment. The data indicates that there are no differences between active- versus sham-acupuncture on subjective health and wellbeing, sleepiness, or mood, nor their AHI or upper airway function and physiology in a clinical OSA population. Once theoretical and methodological limitations of past research were controlled for our data suggest that acupuncture is not an effective treatment for OSA.
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ItemAutonomous learning and achievement motivation in online learning environments( 2017)This program of research developed new understandings of how students’ personal characteristics influence their learning processes in online environments, particularly in a novel mode of online study – massive open online courses, or MOOCs. Based on identified gaps in the educational psychology literature, it established clear trajectories of situational interest in online learning environments, determined distinct relationships between students’ individual interest and their self-directed and self-regulated learning patterns, and employed novel learning analytics techniques to understand these phenomena.
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ItemNeuropsychology and functional brain organisation of working memory in children and adolescents with agenesis of the corpus callosum( 2017)Background: The corpus callosum is the largest brain white matter pathway. Its main function is to coordinate and transfer information between the two hemispheres, thus contributing to higher cognitive functions including working memory (WM). Developmental absence of the corpus callosum, or Agenesis of the Corpus Callosum (AgCC), is one of the most common brain malformations but its consequences on neurobehavioural functioning and functional brain organisation in school-age children are not well understood. Aims: The goal of the current work was: 1) To describe the impact of AgCC on neurobehavioural functioning, including WM functions, in school-age children; and investigate the role of age, social, and neurological factors that might underlie neurobehavioural outcomes in children with AgCC; 2) To investigate the functional brain organisation of WM in school-age children with AgCC using functional magnetic resonance imaging (fMRI). Methods: 28 children diagnosed with AgCC based on MRI and a control sample of 16 typically developing children, aged 8 to 17 years, completed a neurobehavioural assessment and brain imaging with anatomical T1 sequences and an fMRI task (AgCC, n=9; controls, n=16) tapping WM processes, i.e., encoding, maintenance and retrieval. Parents and teachers completed questionnaires to evaluate executive, behavioural and social functions. Results: In our cohort, ~50% experienced general intellectual, academic, executive, social and/or behavioural difficulties and ~20% reached a level comparable to typically developing children. Social risk was found to have an important impact on variability in functional outcomes. Additional brain anomalies or complete AgCC were associated with lower mathematics performance and poorer executive functioning. fMRI findings showed that globally similar brain regions were recruited in the AgCC and the control groups during the WM task, despite significant disparity in brain development, i.e., bilateral occipito-frontal activations during verbal encoding, and bilateral fronto-parietal executive control network during retrieval. However, there were notable differences in activations between groups that might reflect different susceptibility to concurrent tasks during WM, subsequent to different degrees of hemispheric lateralisation during the task. Conclusion: This work constitutes the first comprehensive report of cognitive, executive, behavioural and social consequences of AgCC in school-age children, and provides a first step towards a better understanding of functional brain networks underlying higher cognitive functions in children with AgCC.
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ItemInvestigating complex PTSD for understanding the consequences of trauma in a homeless sample( 2017)Background: The International Classification of Diseases (ICD)-11 that is due for release in 2018 will introduce revised Posttraumatic Stress Disorder (PTSD) criteria as well as a new diagnosis of Complex PTSD. Criteria for this diagnosis of Complex PTSD has been under development, with considerable debate and revision of proposed criteria to this point. This study aimed to test the proposed ICD-11 criteria for PTSD and Complex PTSD in a sample of people who have experienced homelessness. Objective: This study investigated the fit of the ICD-11 Complex PTSD construct with mental health symptoms as reported by a sample of people who have experienced homelessness. This population was chosen to investigate the construct based on previous literature and clinical experience, suggesting that the experience of homelessness is largely synonymous with significant histories of trauma and associated mental health difficulties. Method: Two studies were conducted. First, a pilot study of semi-structured interviews were completed with individuals (N = 20) known to have a history of homelessness and trauma exposure. Findings were used to inform the second study: a cross-sectional empirical investigation of trauma exposure, related symptoms and comorbid mental disorders. Participants (N = 206) were service users who attended homeless support agencies in Melbourne, Australia. Latent Class Analysis (LCA) was used to investigate ICD-11 diagnostic groups in the sample. Results: The sample experienced very high levels of trauma exposure with the majority experiencing childhood abuse and neglect. Four distinct classes of participants emerged in relation to the potential to meet the proposed diagnosis: Class 1, ‘LCA Complex PTSD’ (n=119, 58%), Class 2, ‘LCA no diagnosis’ (n= 34, 16%); Class 3, ‘LCA PTSD’ (n=23, 11%) and finally Class 4, ‘LCA affect, social and self difficulties’ (n= 28, 14%). While those with an ICD-11 Complex PTSD diagnoses fell into the LCA Complex PTSD class, so also did those with an ICD-11 PTSD diagnosis. Conclusions: Our findings provide support for the proposed distinction between Complex PTSD and PTSD. The sample used in this study, of people experiencing homelessness, may have impacted on our findings given they were a highly exposed trauma sample.
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ItemToward a refined model of eye movements in visual enumeration( 2017)This thesis reports three experimental studies that address the question of whether specialised eye movements underlie visual enumeration. Moving our eyes to enumerate sets poses an interesting problem of how and where to look within a set to determine its numerosity. Since the identity and location of each element is irrelevant, existing object-oriented models of spatial attention and saccades are not sufficient to explain enumeration eye movements. Prior research suggests numerosity may be encoded by a dedicated number mechanism within a specialised fronto-parietal network, which partially overlaps with neural circuitry implicated in generating saccades. While this raises the possibility that eye movements play a functional role in enabling exact enumeration of small sets, enumeration eye movements may simply reflect obligatory visual processing demands (i.e., object saliency, gaze heuristics, de-crowding). To rule out these possibilities, we showed identical dot arrays across multiple trials and at multiple orientations (Study 1), had participants determine the numerosity and perceived number of subsets in the same arrays (Study 1), systematically manipulated the opportunity for eye movements by comparing duration-terminated trials with a novel saccade-terminated trial design (Study 2), and replaced dots with letters/numbers and instructed participants to fixate each element in order to provide a comparison with visual search (Study 3). Overall, the findings (1) emphasise the importance of simple visual grouping mechanisms for delineating subsets for efficient enumeration, (2) validate a new saccade-contingent procedure to probe the functional role of saccades in enumeration, and (3) highlight the importance of incorporating the computational complexities of eye movements into existing models of numerical cognition. Extensions to the current experiments are considered, including combined use of neural recording techniques (e.g., EEG, fMRI) to disambiguate obligatory and intentional numerosity encoding/computation mechanisms. The findings are discussed as prerequisites towards a refined model of enumeration eye movements.
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ItemAn emotion-focused parenting program for parents of children with chronic illness: a pilot study( 2017)Parents play a critical role in socializing children’s emotional experiences which contribute to children’s emotional, social and behavioural functioning. However, when children have chronic illness, more emotionally intense and distressing situations can impact parents and their children. This PhD used a mixed-method approach to examine the feasibility, acceptability and outcome of an emotion-focused parenting program, Tuning in to Kids (TIK), for parents of school-aged children with chronic illness when compared to standard paediatric care at 3-month follow-up. Participants were 52 parent-child dyads (intervention = 27, 51.9%) recruited from the Royal Children’s Hospital, Melbourne. Outcomes were obtained from observation of an emotion discussion task as well as parent-reported and child-reported questionnaires. The individually delivered TIK was well attended with high satisfaction and acceptance for its contents and format. Qualitatively, intervention parents reported increased emotional knowledge, awareness and acceptance of their children’s emotions and their own, as well as learning emotion regulation and coaching skills while understanding and reflecting more on their parenting. When compared to a standard paediatric care control group at follow-up using ANCOVA, results showed that parental emotion socialization skills improved with large effect sizes for intervention parents as their emotion coaching increased while emotion dismissing reduced. Intervention parents also reported increased acceptance of negative emotions, better sense of parenting competence and less difficulties in their emotion regulation. Children of intervention parents also showed an improving trend in their socio-emotional functioning. Overall, findings suggest that TIK is a promising intervention for parents of children with chronic illness.
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ItemAn investigation of parent posttraumatic cognitions and mental health outcomes after trauma exposure in children( 2017)Introduction: Parent posttraumatic cognitions have received little attention in the childhood posttraumatic stress literature, yet potentially play an important role in understanding how parents influence children’s recovery after trauma. The manner in which parents respond to their child’s experience is important in the development and treatment of childhood posttraumatic stress disorder (PTSD), and a range of parenting behaviours and parent psychological problems have been linked to childhood posttraumatic stress (Trickey, Siddaway, Meiser-Stedman, Serpell, & Field, 2012; Williamson et al., 2017). To date, limited empirical attention has been given to the nature of cognitions in parents of trauma-exposed children, and the research has been restricted to the use of small item pools, as a multidimensional measure of parent posttraumatic cognitions related to the child’s recovery had yet to be operationalised. The overall aim of this program of research was to develop a measure of parent posttraumatic cognitions for use after a child has experienced a traumatic event, and to examine whether these parent cognitions related to child and parent mental health outcomes. Method: This research had two parts. In Part A, a parent-report questionnaire, the Thinking About Recovery Scale (TARS), was developed to assess specific negative posttraumatic cognitions parents may have after their child is exposed to trauma. The theoretical-rational approach to scale development was used to generate items, which were then subjected to review by experts in the field of childhood trauma. In Part B, the TARS was used in a cross-sectional study, the Thinking About Recovery Project, to examine whether parent posttraumatic cognitions were related to mental health outcomes using a sample of parents and children after children’s experience of accidental injury. Participants were 116 parents and 88 children aged 8-16 years who had been physically injured (e.g., sporting injury, burns, motor vehicle accident) and subsequently admitted to hospital for at least 24 hours. Data collection involved questionnaires to assess parent and child posttraumatic cognitions and mental health outcomes (posttraumatic stress, depression, anxiety, externalising symptoms) between 3 and 6 months post injury. Results: The development and psychometric evaluation of the TARS is reported. The 33-item scale measuring three domains (My child has been permanently damaged; The world is dangerous for my child; Parents should always promote avoidance) demonstrated sound internal consistency and convergent validity when piloted in a sample of 116 parents of children who had been exposed to a serious accidental injury. Posttraumatic cognitions parents had about themselves, the world, and their child’s recovery were significantly associated with both parent and child posttraumatic stress symptoms (PTSS), and a range of other mental health outcomes. A range of parent posttraumatic cognitions were significantly associated with child posttraumatic cognitions. Parent cognitions related to the child mediated the relationship between parents and child PTSS. Discussion and Conclusion: This research was a necessary step in advancing knowledge about parental influences on children’s recovery from traumatic events. Findings provide an empirical basis for ongoing investigation into how parent posttraumatic cognitions may be contributing to the development and maintenance of PTSD symptomatology in parents and children, with particular consideration to cognitions parents have related to their child’s recovery.
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ItemPositive illusion coping styles: adaptive denial, defensiveness, depression and the protection of self-esteem( 2017)The field of positive psychology has been gathering ground over the last decade and positive psychology approaches are now being used in mental health treatment settings. Criticisms of positive psychology include a proliferation in its claims of benefits, a re-packaging of well-established constructs, and a lack of empirical validation. Two common themes in positive psychology literature relate to adaptive psychological mechanisms and emotion regulation. One area that incorporates both of these is Positive Illusions, an entity first proposed by Taylor and Brown (1988). Taylor and Brown (1988) speculated that a functioning system of ‘illusions’ would serve to isolate threat, support self-esteem and maintain optimism and motivation. Sharp contrast was drawn between groups showing these positive biasing tendencies and depressed populations. In the years since this seminal article the construct has been routinely mentioned or utilized without being empirically tested. Adaptive mechanisms that work need to demonstrate their effectiveness both over time and under challenge, however. This study examines whether natural buffering strategies exist in individuals, whether they have utility in the prevention of depression, how independently they function in relation to other psychological constructs, and whether they may be particularly helpful in the presence of negative life events or stressors. A self-report measure was developed which demonstrated construct validity, reliability and consistency of performance over time. A 2-factor structure was clearly the best representation of the data. As represented by this scale, positive illusions (PIS) correlated negatively with depression, and positively with self-esteem, denial, and defensiveness. Higher self-esteem and higher overall PIS predicted significantly lower depression. Structural equation modelling was used to examine the performance of PIS over time, and its independence in relation to other constructs. PIS scores alone, only accounted for 1% of additional variance over and above other predictive variables in relation to depression, but nevertheless this was a statistically significant addition to the model. Self -esteem as an interaction term was found to be highly correlated with other variables and so was not incorporated in the final modelling sequence. Neuroticism was a significant setting factor for PIS, with PIS and neuroticism together accounting for a significant proportion of the variance in depression; yet the PIS construct also demonstrated its independence from Neuroticism. Positive illusions, denial and defensiveness showed very similar levels of correlation to depression – and to each other, implying that there may be a grouping of phenomena that acts similarly or together to influence depression outcomes. Given the negative correlations to Neuroticism, its opposite (i.e., Surgency) is likely to be a factor that allows the possibility of these types of operation to take place.