SSA: Behavioural analysis of cognitive, motivational, and hedonic aspects of reward processing

It is essential for a healthy organism to respond appropriately to rewarding events (e.g. foods). Thus investigating the biological substrates of reward processing offers key insights into both normal behaviour and the deficits seen in psychiatric disorders. Appropriate responses to rewards include aspects of cognition (e.g.veridical representations of the distribution of rewards in the environment), affect (e.g. proportionate hedonic responses to different rewards), and motivation (e.g. sensitivity to the relationship between different rewards and current biological needs). Moreover, disturbances in these responses are key aspects of many psychological and psychiatric disorders and thus this work will have a broader impact. This PhD will examine interacting cognitive, affective, and motivational mechanisms involved in reward processing and explore their biological underpinnings. Initially, it will focus on pharmacological anipulations. Subsequently, it will examine environmental changes (e.g. early life adversity), manipulation of the gut microbiome (e.g., administration of dietary probiotics), and the influence of genetic and age-related risk factors that have been linked to affective abnormalities (e.g. using Tg2576 & WT mice to examine aging and amyloid pathology). Thus the project will investigate the general cognitive, motivational and affective processing of rewards, and examine the common biological and behavioural outputs of different psychological and biological challenges. The project takes a cross-disciplinary approach combining behaviour analysis with pharmacology and neuroscience. This will involve bespoke behaviour analysis methods for assessing cognitive, motivational and hedonic processes. In addition it will use magnetic resonance (MR) spectroscopy to evaluate the impact of the manipulations described above on brain metabolite profiles across theoretically relevant brain regions (e.g., hippocampus, cingulate/frontal cortex; supported by the Cardiff University Experimental MRI Centre). This analysis will be followed up with targeted analysis of protein/receptor expression (e.g., 5-HT receptor subunit expression) using either immunohistochemistry or western blot analyses. Acquisition of expertise in these cutting edge behavioural and neuroscientific tools will position the student who undertakes this project at the forefront of behavioural neuroscience as well as allowing them to develop widely applicable skills in in vivo biology and MRspectroscopy that are in great demand within the academic and industrial research sectors.