A hungry rat will choose a path that leads to food, but the same rat, when thirsty, will ignore that path and seek water instead—this split-second shift in behaviour is what the researchers aim to explain at the level of brain cells and circuits. The problem is that we do not understand how signals from a hungry or thirsty body reach the brain’s decision-making machinery. The ventral hippocampus, a region known for processing context, is a strong candidate, but no one has shown exactly how hunger and thirst information is encoded there, or how it changes the value of a cue or action depending on the animal’s internal state. This gap matters because when this flexible switching fails—when an animal cannot adjust its behaviour to its current need—it may contribute to eating disorders such as obesity and anorexia. This project is fundamental science. It will map, from molecules to circuits to behaviour, how peripheral signals of hunger and thirst are integrated into hippocampal planning. If successful, it will provide a mechanistic framework for understanding how these processes break down in preclinical models of eating disorders, and could eventually point to more targeted treatments. Similar fundamental work on internal-state signalling has already informed therapies for metabolic and psychiatric conditions.
View original technical description
In order to survive, animals must act to address their core physiological needs. For example, when an animal is hungry, it must alter its behaviour in order to increase the likelihood of finding food. Similarly, when thirsty, it must increase the likelihood of finding water. Such flexible and dynamic changes to behavioural goals are crucial for correct planning of ingestive behaviour, and their dysfunction is thought to be a major factor in disorders such as obesity and anorexia. Key to such behaviour is the ability to understand that the outcome associated with an action or cue in the environment is often different dependent on your internal state. As a result, it is often proposed that internal state can act as a context - where appropriate behaviour can be learnt differentially, dependent on whether the animal is hungry or thirsty. However, how peripheral signals of hunger and thirst are integrated into the wider neural circuits essential for contextual planning and decision making - crucial to support such flexible goal directed behaviour - remains unclear. In this proposal we will investigate the hypothesis that the ventral hippocampus - an area key for contextual learning - is crucial to allow flexible behaviour guided by internal state. We will use a combination of state-of-the-art imaging, electrophysiology and optogenetics to directly investigate at the synaptic, cellular and circuit level how hunger and thirst information are represented in the hippocampus, and how this information is used to guide internal state dependent decision making. Our overarching aim is to provide a molecules-to-circuits-to-behaviour description of how internal state information signalled in the periphery can be utilised to guide decision-making behaviour. Our goal is that this research will provide a mechanistic framework to understand how these processes fail in preclinical models of eating disorders, and provide avenues to more effective treatments for these disorders.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know