Dr Bradley Roberts

Dr Bradley Roberts

Junior Research Fellow in Physiology

Biography

Before moving to Oxford, I completed my BA in Neuroscience & Biology at St. Mary's College of Maryland. As an undergraduate Research Assistant, I worked in the laboratory of Aileen Bailey investigating the role of orexin in the basal forebrain on cortical-dependant executive functions. Subsequently, I moved to the University of Maryland School of Medicine as a Research Assistant in the laboratory of Brian Mathur, where I investigated the role of striatal fast-spiking interneurons in encoding movement and aberrant activity of theses interneurons in alcoholism.

I completed my DPhil in the laboratory of Stephanie Cragg in the Department of Physiology, Anatomy and Genetics at the University of Oxford and at Christ Church College. For my DPhil research, I examined the regulation of striatal dopamine release by local GABA signalling and dysfunction in Parkinson’s disease models. I joined St. John’s College as a Junior Research Fellow in Physiology in the Autumn of 2019.

Research Interests

The neurotransmitter dopamine, in the brain region called the striatum, is vitally important for our everyday actions and motivations. Without dopamine we develop Parkinson's disease and cannot move, but with too much dopamine, we develop addictions. If we could understand more about how dopamine is controlled by the brain, we might better understand how the brain regulates these behaviours, and how we might treat them better in disease.

My current research focuses on understanding how non-neuronal cells called astrocytes might control dopamine neurons and dopamine release in the striatum. Astrocytes are almost as abundant as neurons in the brain but our understanding of astrocyte function in brain circuits lags significantly behind our understanding of neuronal function. New experimental tools to modulate astrocyte activity has revealed that astrocytes might play a more powerful role that originally believed in directly regulating neurotransmitter release. My research is examining the fundamentally important questions of whether astrocytes in the striatum can dynamically modulate dopamine release, the mechanisms through which they might do it, and whether this impacts on dopamine-dependent behaviours. I am also working to understand whether there are changes to the biology of astrocytes in the striatum in Parkinson's disease, and how these changes might impact negatively on dopamine function.  

My research is funded by the John Fell OUP Research Fund and a project grant awarded by The Medical Research Council, and is in collaboration with Professor Stephanie Cragg and the Oxford Parkinson’s Disease Centre. 

Teaching

At the University level, I give lectures, tutorials and seminars for the undergraduate (pre-clinical) biomedical students on Neuroscience topics related to neurotransmission, neurophysiology and the basal ganglia. I also regularly assist with neuroanatomy practical classes for second year medical students. In the laboratory, I supervise both undergraduate and postgraduate research projects. 

Highlighted Publications

Roberts BM, Doig NM, Brimblecombe KR, Lopes EL, Siddorn RE, Threlfell S, Connor-Robson N, Bengoa-Vergniory N, Pasternack N, Wade-Martins R, Magill PJ, Cragg SJ (2020) GABA uptake transporters support dopamine release in dorsal striatum with maladaptive downregulation in a parkinsonism model. Nature Communications 11, 4958. https://doi.org/10.1038/s41467-020-18247-5 

Roberts BM*, White MG*, Patton MH, Mu C, Chen R, Mathur BN (2019) Ensemble encoding of action velocity dynamics by striatal fast-spiking interneurons. Brain Structure and Function 224: 2567-2576. (*co-first authors). https://doi.org/10.1007/s00429-019-01908-7 

Lopes EF*, Roberts BM*, Siddorn RE, Clements MA, Cragg SJ (2019) Inhibition of nigrostriatal dopamine release by striatal GABAA and GABAB receptors. Journal of Neuroscience 39: 1058-1065. (*co-first authors). https://doi.org/10.1523/JNEUROSCI.2028-18.2018