The relationship between Hippocampal asymmetry and working memory processing in combat-related PTSD: a monozygotic twin study

BACKGROUND: PTSD is associated with reduction in hippocampal volume and abnormalities in hippocampal function. Hippocampal asymmetry has received less attention, but potentially could indicate lateralised differences in vulnerability to trauma. The P300 event-related potential component reflects the immediate processing of significant environmental stimuli and has generators in several brain regions including the hippocampus. P300 amplitude is generally reduced in people with PTSD. METHODS: Our study examined hippocampal volume asymmetry and the relationship between hippocampal asymmetry and P300 amplitude in male monozygotic twins discordant for Vietnam combat exposure. Lateralised hippocampal volume and P300 data were obtained from 70 male participants, of whom 12 had PTSD. We were able to compare (1) combat veterans with current PTSD; (2) their non-combat-exposed co-twins; (3) combat veterans without current PTSD and (4) their non-combat-exposed co-twins. RESULTS: There were no significant differences between groups in hippocampal asymmetry. There were no group differences in performance of an auditory oddball target detection task or in P300 amplitude. There was a significant positive correlation between P300 amplitude and the magnitude of hippocampal asymmetry in participants with PTSD. CONCLUSIONS: These findings suggest that greater hippocampal asymmetry in PTSD is associated with a need to allocate more attentional resources when processing significant environmental stimuli.Timothy Hall, Cherrie Galletly, C.R. Clark, Melinda Veltmeyer, Linda J. Metzger, Mark W. Gilbertson, Scott P. Orr, Roger K. Pitman and Alexander McFarlan

Do people with schizophrenia lack emotional intelligence?

Extent: 8 p.Social cognition is a domain of cognitive function that includes the ability to understand and manage social interactions. Emotional intelligence (EI) has been identified as a component of social cognition and is defined as the ability to identify, use, understand, and manage emotions. Neurocognitive impairments are known to be associated with poorer social function in people with schizophrenia, but less is known about the relationships between EI, neurocognition, and social function. The current study assessed EI using the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) in 20 people with schizophrenia and 20 controls. The schizophrenia group had significantly lower scores on all measures of EI and demonstrated poorer neurocognition and social functioning than controls. The difference between schizophrenia and control groups was greatest for the Understanding Emotions Branch of the MSCEIT. The neurocognition score and total EI score accounted for 18.3% of the variance in social function in the control group and 9.1% of the variance in social function in the schizophrenia group. Our results suggest that a total EI score is not a useful predictor of overall social function and it may be more clinically useful to develop an individual profile of social cognitive abilities, including EI, to form a remediation program.Sara Dawson, Lisa Kettler, Cassandra Burton and Cherrie Galletl

Topological Structure of the QCD Vacuum Revealed by Overlap Fermions

Overlap fermions preserve a remnant of chiral symmetry on the lattice. They are a powerful tool to investigate the topological structure of the vacuum of Yang-Mills theory and full QCD. Recent results concerning the localization of topological charge and the localization and local chirality of the overlap eigenmodes are reported. The charge distribution is radically different, if a spectral cut-off for the Dirac eigenmodes is applied. The density q(x) is changing from the scale-a charge density (with full lattice resolution) to the ultraviolet filtered charge density. The scale-a density, computed on the Linux cluster of LRZ, has a singular, sign-coherent global structure of co-dimension 1 first described by the Kentucky group. We stress, however, the cluster properties of the UV filtered topological density resembling the instanton picture. The spectral cut-off can be mapped to a bosonic smearing procedure. The UV filtered field strength reveals a high degree of (anti)selfduality at "hot spots" of the action. The fermionic eigenmodes show a high degree of local chirality. The lowest modes are seen to be localized in low-dimensional space-time regions.Comment: 13 pages, 11 figures, accepted to appear in the Proceedings of "HLRB, KONWIHR and Linux-Cluster: Review, Results and Future Projects Workshop", Leibniz Rechenzentrum Munich, December 200

Does switching between high frequency rTMS and theta burst stimulation improve depression outcomes?

Leo Chen, Elizabeth H.X. Thomas, Pakin Kaewpijit, Aleksandra Miljevic, Lisa Hahn, Alexandra Lavale, Kate E. Hoy, Cherrie Galletly, Paul B. Fitzgeral

Brain antibodies in the cortex and blood of people with schizophrenia and controls

The immune system is implicated in the pathogenesis of schizophrenia, with elevated proinflammatory cytokine mRNAs found in the brains of ~40% of individuals with the disorder. However, it is not clear if antibodies (specifically immunoglobulin-γ (IgG)) can be found in the brain of people with schizophrenia and if their abundance relates to brain inflammatory cytokine mRNA levels. Therefore, we investigated the localization and abundance of IgG in the frontal cortex of people with schizophrenia and controls, and the impact of proinflammatory cytokine status on IgG abundance in these groups. Brain IgGs were detected surrounding blood vessels in the human and non-human primate frontal cortex by immunohistochemistry. IgG levels did not differ significantly between schizophrenia cases and controls, or between schizophrenia cases in 'high' and 'low' proinflammatory cytokine subgroups. Consistent with the existence of IgG in the parenchyma of human brain, mRNA and protein of the IgG transporter (FcGRT) were present in the brain, and did not differ according to diagnosis or inflammatory status. Finally, brain-reactive antibody presence and abundance was investigated in the blood of living people. The plasma of living schizophrenia patients and healthy controls contained antibodies that displayed positive binding to Rhesus macaque cerebellar tissue, and the abundance of these antibodies was significantly lower in patients than controls. These findings suggest that antibodies in the brain and brain-reactive antibodies in the blood are present under normal circumstances.LJ Glass, D Sinclair, D Boerrigter, K Naude, SJ Fung, D Brown, VS Catts, P Tooney, M O’Donnell, R Lenroot, C Galletly, D Liu, TW Weickert and C Shannon Weicker

Participatory Action Research-Dadirri-Ganma, using Yarning: methodology co-design with Aboriginal community members

Background: Appropriate choice of research design is essential to rightly understand the research problem and derive optimal solutions. The Comorbidity Action in the North project sought to better meet the needs of local people affected by drug, alcohol and mental health comorbidity. The aim of the study focused on the needs of Aboriginal peoples and on developing a truly representative research process. A methodology evolved that best suited working with members of a marginalised Aboriginal community. This paper discusses the process of co-design of a Western methodology (participatory action research) in conjunction with the Indigenous methodologies Dadirri and Ganma. This co-design enabled an international PhD student to work respectfully with Aboriginal community members and Elders, health professionals and consumers, and non-Indigenous service providers in a drug and alcohol and mental health comorbidity project in Adelaide, South Australia. Methods The PhD student, Aboriginal Elder mentor, Aboriginal Working Party, and supervisors (the research team) sought to co-design a methodology and applied it to address the following challenges: the PhD student was an international student with no existing relationship with local Aboriginal community members; many Aboriginal people deeply distrust Western research due to past poor practices and a lack of implementation of findings into practice; Aboriginal people often remain unheard, unacknowledged and unrecognised in research projects; drug and alcohol and mental health comorbidity experiences are often distressing for Aboriginal community members and their families; attempts to access comorbidity care often result in limited or no access; and Aboriginal community members experience acts of racism and discrimination as health professionals and consumers of health and support services. The research team considered deeply how knowledge is shared, interpreted, owned and controlled, by whom and how, within research, co-morbidity care and community settings. The PhD student was supported to co-design a methodology that was equitable, democratic, liberating and life-enhancing, with real potential to develop feasible solutions.Results The resulting combined Participatory Action Research (PAR)-Dadirri-Ganma methodology sought to create a bridge across Western and Aboriginal knowledges, understanding and experiences. Foundation pillars of this bridge were mentoring of the PhD student by senior Elders, who explained and demonstrated the critical importance of Yarning (consulting) and Indigenous methodologies of Dadirri (deep listening) and Ganma (two-way knowledge sharing), and discussions among all involved about the principles of Western PAR.. Conclusions Concepts within this paper are shared from the perspective of the PhD student with the permission and support of local Elders and Working Group members. The intention is to share what was learned for the benefit of other students, research projects and community members who are beginning a similar journey.Hepsibah Sharmil, Janet Kelly, Margaret Bowden, Cherrie Galletly, Imelda Cairney, Coral Wilso

Accelerated theta burst stimulation for the treatment of depression: a randomised controlled trial

INTRODUCTION: Theta burst pattern repetitive transcranial magnetic stimulation (TBS) is increasingly applied to treat depression. TBS's brevity is well-suited to application in accelerated schedules. Sizeable trials of accelerated TBS are lacking; and optimal TBS parameters such as stimulation intensity are not established. METHODS: We conducted a three arm, single blind, randomised, controlled, multi-site trial comparing accelerated bilateral TBS applied at 80 % or 120 % of the resting motor threshold and left unilateral 10 Hz rTMS. 300 patients with treatment-resistant depression (TRD) were recruited. TBS arms applied 20 bilateral prefrontal TBS sessions over 10 days, while the rTMS arm applied 20 daily sessions of 10 Hz rTMS to the left prefrontal cortex over 4 weeks. Primary outcome was depression treatment response at week 4. RESULTS: The overall treatment response rate was 43.7 % and the remission rate was 28.2 %. There were no significant differences for response (p = 0.180) or remission (p = 0.316) across the three groups. Response rates between accelerated bilateral TBS applied at sub- and supra-threshold intensities were not significantly different (p = 0.319). Linear mixed model analysis showed a significant effect of time (p < 0.01), but not rTMS type (p = 0.680). CONCLUSION: This is the largest accelerated bilateral TBS study to date and provides evidence that it is effective and safe in treating TRD. The accelerated application of TBS was not associated with more rapid antidepressant effects. Bilateral sequential TBS did not have superior antidepressant effect to unilateral 10 Hz rTMS. There was no significant difference in antidepressant efficacy between sub- and supra-threshold accelerated bilateral TBS.Leo Chen, Elizabeth H.X.Thoma, Pakin Kaewpijit, Aleksandra Miljevic, Rachel Hughes, Lisa Hahn ... et al