Assessing reward-entrainment as a means to activating and identifying the food-entrainable pacemaker

Optimal functioning requires organisms to anticipate and adapt to daily environmental changes driven by the cycle of the sun. Entrainment is the process by which daily rhythms of behaviour and physiology are synchronized to the environment. Shift-workers and air travelers are often out of sync with their environment due to a mismatch between their internal clock and the external environment. This dyssynchrony leads to general discomfort and reduced performance known as shift-work malaise or jet-lag. This has a detrimental effect on health, performance, levels of productivity and quality of life. Glenn Landry aims to achieve a better understanding of the mechanisms of entrainment. In mammals, an area of the brain called the suprachiasmatic nucleus acts as a master pacemaker. In animal models that have access to food and water without restriction, damage to this area of the brain eliminates all daily rhythms. However, if food is restricted to one to two meals at a fixed time each day, these animal models are still capable of anticipating the feeding time. This shows that a separate pacemaker exists for anticipating food. But identifying this food-entrainable pacemaker has been a challenge since many brain structures are activated during food restriction, making it difficult to isolate the pacemaker from background activity. Landry is testing a recently developed strategy to filter out this background activity. By using a number of different stimuli capable of activating the food-entrainable pacemaker, he aims to isolate this pacemaker by identifying brain areas activated in common across these stimuli. Landry hopes identifying the food-entrainable pacemaker could ultimately lead to new approaches to re-setting the clocks of shift-workers and air travelers, improving health and productivity.