Cognitive & Behavioural Neuroscience Seminar: Reduced reactivity to food cues: New insights on the role of intrinsic excitability alterations on nucleus accumbens neuronal ensembles
Dr Eisuke Koya - (School of Psychology, University of Sussex)
Tuesday, 06 February 2018, 1pm to 2pm
Schlich Lecture Theatre, Department of Plant Sciences, South Parks Rd, OX1 3RB
Hosted by Anna Huber
Both humans and animals need to respond appropriately to cues that predict the availability of food for nutrient procurement. For example, we may be on the lookout for a supermarket sign when hungry while walking in town, or wild mice may follow sweet smells that lead them towards ripe berries. Such reactive actions to cues depend on the brain’s ability to efficiently store and retrieve learned associations about food and its predictive cues (‘food-cue’ associations). However, in certain individuals, the reactivity to these cues can be undesirable when they evoke food cravings. Also, if mismanaged these episodes result in excessive eating leading to obesity. It is therefore important to understand the neurobehavioral factors that can prevent harmful responses to cues connected with food.
Although the brain areas implicated in food-cue associations have been well-characterised, the specific neuronal populations that help encode these associations have not been fully elucidated yet. Animal research has allowed us to obtain better insight of the precise mechanisms behind how these associations are formed and established at the level individual neurons such as their activity patterns. Moreover, animal studies allow the characterisation of how individual neurons undergo physiological changes such as changes in their intrinsic excitability properties, which are thought to be critical for information storage and retrieval. We and others have shown that food-cue associations are encoded in specific patterns of activity from a population of sparsely distributed neurons, called ‘neuronal ensembles’ in brain areas implicated in reward, such as the nucleus accumbens. In my talk, I will discuss how factors such as the strength of food-cue associations, the current value of food reward, and cognitive and physical stimulation, modulate cue-evoked food-seeking and the activity patterns and excitability properties of accumbens neuronal ensembles.