Melbourne School of Psychological Sciences - Research Publications

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    Cortical thinning 3 years after ischaemic stroke is associated with cognitive impairment and APOE ε4.
    Salah Khlif, M ; Egorova-Brumley, N ; Bird, LJ ; Werden, E ; Brodtmann, A (Elsevier BV, 2022)
    Cortical thinning has been described in many neurodegenerative diseases and used for both diagnosis and disease monitoring. The imaging signatures of post-stroke vascular cognitive impairment have not been well described. We investigated the trajectory of cortical thickness over 3 years following ischaemic stroke compared to healthy stroke-free age- and sex-matched controls. We also compared cortical thickness between cognitively normal and impaired stroke survivors, and between APOE ɛ4 carriers and non-carriers. T1-weighted MRI and cognitive data for 90 stroke survivors and 36 controls from the Cognition And Neocortical Volume After Stroke (CANVAS) study were used. Cortical thickness was estimated using FreeSurfer volumetric reconstruction according to the Desikan-Killiany parcellation atlas. Segmentation inaccuracies were manually corrected and infarcted ipsilesional vertices in cortical thickness maps were identified and excluded using stroke lesion masks traced a-priori. Mixed-effects regression was used to compare cortical thickness cross-sectionally between groups and longitudinally between timepoints. Healthy control and stroke groups did not differ on demographics and most clinical characteristics, though controls were less likely to have atrial fibrillation. Age was negatively associated with global mean cortical thickness independent of sex or group, with women in both groups having significantly thicker cortex. Three months post-stroke, cortical thinning was limited and focal. From 3 months to 3 years, the rate of cortical thinning in stroke was faster compared to that in healthy controls. However, this difference in cortical thinning rate could not survive family-wise correction for multiple comparisons. Yet, cortical thinning at 3 years was found more spread especially in ipsilesional hemispheres in regions implicated in motor, sensory, and memory processing and recovery. The cognitively impaired stroke survivors showed greater cortical thinning, compared to controls, than those who were cognitively normal at 3 years. Also, carriers of the APOE ɛ4 allele in stroke exhibited greater cortical thinning independent of cognitive status. The temporal changes of cortical thickness in both healthy and stroke cohorts followed previously reported patterns of cortical thickness asymmetry loss across the human adult life. However, this loss of thickness asymmetry was amplified in stroke. The post-stroke trajectories of cortical thickness reported in this study may contribute to our understanding of imaging signatures of vascular cognitive impairment.
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    White matter microstructure and verbal fluency
    Egorova-Brumley, N ; Liang, C ; Khlif, MS ; Brodtmann, A (Springer, 2022-10-17)
    Poor performance on verbal fluency tasks is associated with an increased risk of post-stroke cognitive impairment. Grey matter regions supporting verbal fluency have been identified via lesion-symptom mapping, but the links between verbal fluency and white matter structure remain less well described. We examined white matter correlates of semantic (Category Fluency Animals) and phonemic or lexical fluency (COWAT FAS) after stroke, accounting for stroke severity measured with the National Institutes of health Stroke Scale (NIHSS), age, sex, and level of education. White matter fibre density and cross-section measures were automatically extracted from 72 tracts, using MRtrix and TractSeg software in 72 ischaemic stroke survivors assessed 3 months after their event. We conducted regression analyses separately for phonemic and semantic fluency for each tract. Worse semantic fluency was associated with lower fibre density in several tracts, including the arcuate fasciculus, superior longitudinal fasciculus, inferior occipito-frontal fasciculus, inferior longitudinal fasciculus, optic radiation, striato-occipital, thalamo-occipital tracts, and inferior cerebellar peduncle. Our stroke sample was heterogenous with largely non-overlapping and predominantly right-lateralised lesions (lesion distribution: left N = 27, right N = 43, bilateral N = 2), dissimilar to previous studies of verbal fluency. Yet, the tracts we identified as correlates of semantic fluency were all left-lateralised. No associations between phonemic fluency performance and fibre density metrics in any of the white matter tracts we extracted survived correction for multiple comparisons, possibly due to the limitations in the selection of tracts and sample characteristics. We conclude that when accounting for the effects of stroke severity, sex, age, and education, semantic fluency is associated with white matter microstructure in the left arcuate fasciculus, superior longitudinal fasciculus, and several occipital tracts, possibly reflecting the disconnection in the sagittal stratum. Our results obtained with fixel-based analysis, complement previous findings obtained with lesions-symptom mapping and neurodegenerative approaches.
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    The effects of Aboriginal tertiary students' perceived experiences of racism and of cultural resilience on educational engagement
    Gibbs, J ; Paradies, Y ; Gee, G ; Haslam, N (The University of Queensland, )
    Racism pervasively impacts the lives of Aboriginal and Torres Strait Islander peoples and is a substantial barrier to accessing, engaging and succeeding within secondary education. Cultural resilience and support have been identified as critical to Aboriginal success within racist institutions. However, research examining experiences of racism and cultural resilience among Aboriginal tertiary students is limited. This study explored the relationship between racism, cultural resilience, and educational engagement and academic outcomes in a sample of these students (N = 63). We proposed that higher perceived racism would be associated with lower engagement and academic outcomes. The study also developed a new measure of Aboriginal tertiary students’ experience of racism during their studies, which demonstrated good reliability and validity. Experiencing racism was associated with perceiving a less supportive learning environment, and with lower learning outcomes, developmental outcomes and overall student satisfaction.
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    "Instant Happiness": Smartphones as tools for everyday emotion regulation
    Shi, Y ; Koval, P ; Kostakos, V ; Goncalves, J ; Wadley, G (Elsevier, 2023-02-01)
    Smartphone use has become an indispensable aspect of daily life for billions of people. Increasingly, researchers are examining the impact of smartphone use upon psychological well-being. However, little research has investigated how people deliberately use their smartphones to shape affective states; in other words, how smartphones are used as tools to support everyday emotion regulation. In this paper, we report a study that uses quantitative (experience sampling) and qualitative (semi-structured interview) methods to examine when and how people use smartphones to regulate emotions in everyday life, and the associated psychological consequences. Participants report spending a significant amount of time using their smartphones for emotion regulation, in particular to cope with unpleasant feelings such as boredom and stress. They report that smartphone-mediated emotion regulation is effective for attaining desired affective states. However, the perceived emotional benefits of smartphone emotion regulation do not emerge in lagged analyses predicting changes in momentary mood across a few hours, suggesting that emotional benefits may be transient or may reflect self-report biases. Participants discuss their perceptions of smartphone-supported emotion regulation in relation to smartphone addiction. This study provides evidence on how people use their smartphones for emotion regulation, and contributes to better understanding the complex relationship between smartphone use and emotional wellbeing.
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    Protecting the Planet or Destroying the Universe? Understanding Reactions to Space Mining
    Hornsey, MJ ; Fielding, KS ; Harris, EA ; Bain, PG ; Grice, T ; Chapman, CM (MDPI, 2022-04-01)
    There is currently a surge in interest from both private and government sectors in developing technology for mining asteroids and the moon (“space mining”). One of the key benefits highlighted by advocates of space mining is that it minimizes the usual problems associated with mining on earth in terms of pollution, environmental degradation, and encroachment on human habitats. Two studies—one conducted on a 27-nation sample (N = 4819), the other conducted in the U.S. (N = 607)—provide the first test of the assumed (but never studied) notion that space mining is more palatable to the public than terrestrial mining. Both studies indicate broad support for asteroid mining: levels of support were reliably above the mid-point, and much greater than for other forms of frontier mining such as mining the ocean floor, mining Antarctica, mining the Alaskan tundra, and lunar mining. Unlike terrestrial mining, community attitudes toward mining asteroids were largely non-ideological; support was not correlated with perceptions of ecological fragility, political ideology, or individualistic/hierarchical worldviews. In summary, the current studies suggest that mining companies have a “social license to operate” for mining asteroids, but less so for lunar mining.
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    Clinical guidelines for the use of lifestyle-based mental health care in major depressive disorder: World Federation of Societies for Biological Psychiatry (WFSBP) and Australasian Society of Lifestyle Medicine (ASLM) taskforce
    Marx, W ; Manger, SH ; Blencowe, M ; Murray, G ; Ho, FY-Y ; Lawn, S ; Blumenthal, JA ; Schuch, F ; Stubbs, B ; Ruusunen, A ; Desyibelew, HD ; Dinan, TG ; Jacka, F ; Ravindran, A ; Berk, M ; O'Neil, A (TAYLOR & FRANCIS LTD, 2022-09-20)
    OBJECTIVES: The primary objectives of these international guidelines were to provide a global audience of clinicians with (a) a series of evidence-based recommendations for the provision of lifestyle-based mental health care in clinical practice for adults with Major Depressive Disorder (MDD) and (b) a series of implementation considerations that may be applicable across a range of settings. METHODS: Recommendations and associated evidence-based gradings were based on a series of systematic literature searches of published research as well as the clinical expertise of taskforce members. The focus of the guidelines was eight lifestyle domains: physical activity and exercise, smoking cessation, work-directed interventions, mindfulness-based and stress management therapies, diet, sleep, loneliness and social support, and green space interaction. The following electronic bibliographic databases were searched for articles published prior to June 2020: PubMed, EMBASE, The Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Methodology Register), CINAHL, PsycINFO. Evidence grading was based on the level of evidence specific to MDD and risk of bias, in accordance with the World Federation of Societies for Biological Psychiatry criteria. RESULTS: Nine recommendations were formed. The recommendations with the highest ratings to improve MDD were the use of physical activity and exercise, relaxation techniques, work-directed interventions, sleep, and mindfulness-based therapies (Grade 2). Interventions related to diet and green space were recommended, but with a lower strength of evidence (Grade 3). Recommendations regarding smoking cessation and loneliness and social support were based on expert opinion. Key implementation considerations included the need for input from allied health professionals and support networks to implement this type of approach, the importance of partnering such recommendations with behaviour change support, and the need to deliver interventions using a biopsychosocial-cultural framework. CONCLUSIONS: Lifestyle-based interventions are recommended as a foundational component of mental health care in clinical practice for adults with Major Depressive Disorder, where other evidence-based therapies can be added or used in combination. The findings and recommendations of these guidelines support the need for further research to address existing gaps in efficacy and implementation research, especially for emerging lifestyle-based approaches (e.g. green space, loneliness and social support interventions) where data are limited. Further work is also needed to develop innovative approaches for delivery and models of care, and to support the training of health professionals regarding lifestyle-based mental health care.
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    Motivated inquiry: ideology shapes responses to the Christian Porter rape allegation
    Weaving, M ; Fine, C ; Haslam, N (TAYLOR & FRANCIS LTD, 2022-12-31)
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    Cerebral Arterial Asymmetries in the Neonate: Insight into the Pathogenesis of Stroke
    van Vuuren, AJ ; Saling, M ; Rogerson, S ; Anderson, P ; Cheong, J ; Solms, M (MDPI, 2022-03-01)
    Neonatal and adult strokes are more common in the left than in the right cerebral hemisphere in the middle cerebral arterial territory, and adult extracranial and intracranial vessels are systematically left-dominant. The aim of the research reported here was to determine whether the asymmetric vascular ground plan found in adults was present in healthy term neonates (n = 97). A new transcranial Doppler ultrasonography dual-view scanning protocol, with concurrent B-flow and pulsed wave imaging, acquired multivariate data on the neonatal middle cerebral arterial structure and function. This study documents for the first-time systematic asymmetries in the middle cerebral artery origin and distal trunk of healthy term neonates and identifies commensurately asymmetric hemodynamic vulnerabilities. A systematic leftward arterial dominance was found in the arterial caliber and cortically directed blood flow. The endothelial wall shear stress was also asymmetric across the midline and varied according to vessels’ geometry. We conclude that the arterial structure and blood supply in the brain are laterally asymmetric in newborns. Unfavorable shearing forces, which are a by-product of the arterial asymmetries described here, might contribute to a greater risk of cerebrovascular pathology in the left hemisphere.
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    Automatic morpheme identification across development: Magnetoencephalography (MEG) evidence from fast periodic visual stimulation
    Pescuma, VN ; Ktori, M ; Beyersmann, E ; Sowman, PF ; Castles, A ; Crepaldi, D (FRONTIERS MEDIA SA, 2022-09-07)
    The present study combined magnetoencephalography (MEG) recordings with fast periodic visual stimulation (FPVS) to investigate automatic neural responses to morphemes in developing and skilled readers. Native English-speaking children (N = 17, grade 5-6) and adults (N = 28) were presented with rapid streams of base stimuli (6 Hz) interleaved periodically with oddballs (i.e., every fifth item, oddball stimulation frequency: 1.2 Hz). In a manipulation-check condition, tapping into word recognition, oddballs featured familiar words (e.g., roll) embedded in a stream of consonant strings (e.g., ktlq). In the experimental conditions, the contrast between oddball and base stimuli was manipulated in order to probe selective stem and suffix identification in morphologically structured pseudowords (e.g., stem + suffix pseudowords such as softity embedded in nonstem + suffix pseudowords such as trumess). Neural responses at the oddball frequency and harmonics were analyzed at the sensor level using non-parametric cluster-based permutation tests. As expected, results in the manipulation-check condition revealed a word-selective response reflected by a predominantly left-lateralized cluster that emerged over temporal, parietal, and occipital sensors in both children and adults. However, across the experimental conditions, results yielded a differential pattern of oddball responses in developing and skilled readers. Children displayed a significant response that emerged in a mostly central occipital cluster for the condition tracking stem identification in the presence of suffixes (e.g., softity vs. trumess). In contrast, adult participants showed a significant response that emerged in a cluster located in central and left occipital sensors for the condition tracking suffix identification in the presence of stems (e.g., softity vs. stopust). The present results suggest that while the morpheme identification system in Grade 5-6 children is not yet adult-like, it is sufficiently mature to automatically analyze the morphemic structure of novel letter strings. These findings are discussed in the context of theoretical accounts of morphological processing across reading development.