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Cognitive and decision-making problems associated with psychotic disorders like schizophrenia are considered the largest burden for these individuals. They also predict poor functional outcomes, such as maintaining work, social networks, and independent living. I am particularly interested in the relationship between decision-making problems and psychotic symptoms in these disorders; will improving decision-making also reduce psychotic symptoms? To that end, I focus on decision-making tasks that are reliant on brain areas and networks that are implicated in psychosis.

My work aims to understand how corticostriatal circuitry drives decision-making processes, and how this is altered in those with schizophrenia and psychosis. I have taken advantage of my collaborations with basic scientists and clinical researchers with a broad range of expertise to establish a cross-species program of research focussed on decision-making. My research is guided by two fundamental questions:

1. Do decision-making problems in schizophrenia and other psychotic disorders contribute to psychotic symptoms?
2. How can we leverage the mechanistic tools available in rodent neuroscience to identify causative common substrates underlying decision-making problems (and by proxy psychotic symptoms)?

I received my Bachelor's in Biology (2001) from Yarmouk University in Jordan, followed by postgraduate degrees from the University of Houston in Houston-Texas (2002-2007). My studies are integrative in nature, joining the best of both the Neuroscience world and Circadian Biology (the study of biological clocks). In the laboratory of Prof. Arnold Eskin, I investigated how processes as complex as learning and memory are modulated by biological clocks i.e. the circadian (about 24 hours) system, using Aplysia californica as the experimental model. After completing my Master's in Science in 2005, my research focused on the mechanism by which biological clocks modulate learning and memory. This work was performed in the laboratories of Prof. Gregg Cahill and Prof. Greg Roman, experts in chronobiology and behavioral neuroscience, respectively. Using Zebrafish as a model system, I investigated the role of melatonin, a night-time restricted hormonal signal, in modulating long-term memory consolidation. My findings, published in Science in 2007, shows that the circadian system via the cyclic night-time confined synthesis/release of melatonin “the hormone of darkness” functions as a modulator, shaping daily variations in the efficiency by which memories are processed. After receiving my Ph.D. in 2007, I joined as a postdoctoral fellow the laboratory of the pharmacologist and melatonin researcher Prof. Margarita Dubocovich. My postdoctoral work engaged in elucidating the role of melatonin in circadian physiology and pharmacology during development and ageing in rodents (Mus musculus) and non-human primates (Macaca mulatta) at the Feinberg School of Medicine (Northwestern University-Chicago) and the State University of New York (SUNY). From 2010-2015, I held a teaching/research position in the Dr. Senckenbergische Anatomy and the Dept. of Neurology at the Goethe University in Frankfurt-Germany. During this time, I was involved in teaching gross human anatomy while continuing my endeavor in understanding the mechanistics involved in shaping memory processes (acquisition, consolidation and retrieval) by the circadian system.

I am a neuroscientist investigating how cellular signalling and neuron–glia interactions shape brain development, neural circuit function and myelination across the lifespan, and how disruption of these processes contributes to neurodevelopmental and neurodegenerative disorders. My research focuses on neural progenitor cells, oligodendrocyte biology, myelination and neural circuit function, with the broader goal of understanding disease mechanisms and identifying therapeutic targets that can improve the treatment of neurological disorders.

I completed my PhD at the University of Tasmania, investigating ion channel signalling in oligodendrocyte progenitor cells and its role in cell survival, neural circuit function and myelination. I subsequently undertook postdoctoral research at The University of Queensland, including at the Queensland Brain Institute, where I investigated neural progenitor function, neuronal migration and cortical development in models of neurodevelopmental disorders. At Mater Research–UQ, my research has focused on oligodendrocyte dysfunction, myelination and cellular signalling in neurological disease, including multiple sclerosis-like pathology.

Across these research programs, I have developed expertise in developmental and cellular neuroscience, neural progenitor biology, neuron–glia interactions, oligodendrocyte biology, myelination and neural circuit function, using molecular and cellular approaches, advanced microscopy, electrophysiology, animal models and behavioural neuroscience. My broader research direction is to understand how dysfunction across different neural cell populations contributes to disease progression and how this knowledge can be translated into new approaches to prevent, treat or modify neurological disease.

Alongside my research, I contribute to tertiary teaching, student supervision and scientific communication across neuroscience, psychology and biomedical sciences. I am particularly interested in research-informed education and in developing the next generation of scientists by sharing scientific knowledge, technical expertise and practical research skills.

Dr Adam Walker received his BSc(Hons) in Biochemistry from the University of Tasmania, and PhD in Neuroscience from the Florey Institute of Neuroscience and Mental Health at the University of Melbourne, focused on understanding the molecular mechanisms of motor neuron disease (MND). He undertook a postdoctoral fellowship with Professor Virginia Lee at the Center for Neurodegenerative Disease Research, University of Pennsylvania (2011-2015), developing new transgenic TDP-43 mouse models of disease. Dr Walker was previously an NHMRC CJ Martin Overseas Biomedical Research Fellow and was awarded an NHMRC RD Wright Career Development Fellowship (2018-2022), to continue his research on neurodegenerative diseases.

He was Group Leader in the Clem Jones Centre for Ageing Dementia Research at the Queensland Brain Institute 2018-2025, and is now Honorary Professor.

My research interests are centred around the structure and function of venom and silk polypeptides produced by arthropods, and their use in biotechnology and medicine. I am a Postdoctoral Fellow in the King laboratory in the Institute for Molecular Bioscience, the University of Queensland, Australia. Currently, I am investigating the composition, function and evolution of neglected insect venoms produced by assassin bugs (Hemiptera: Reduviidae), robber flies (Diptera: Asilidae) and nettle caterpillars (Lepidoptera: Limacodidae).