Effects of hunger state on food-related brain responses across the lifespan

Thesis aims The studies conducted in this thesis were part of the Full4Health project. The aims of the Full4Health project were to assess the differences in the brain responses to food presentation and food choice and how these responses are modulated by hunger and gut signals in lean and obese subjects across the lifespan. In this thesis we focus on the effect of hunger state on food-related brain responses across the lifespan. In addition, to be able to better examine alterations in reward processing we aimed to establish the effects of hunger state and weight-status on monetary reward processing. Thesis overview In Chapter 2 we present a standardized food image photographing protocol and image database tested and validated across countries which can be used in food cue research. In Chapter 3 we utilize these images in a sophisticated fMRI food choice design in which food choices are matched on individual preference but differ in caloric content. A group of healthy normal-weight adults performed this choice task in de absence of hunger. In Chapter 4 the standardized food images are used in a food viewing fMR task. With this task, the effect of hunger state on the brain responses to low and high calorie food cues across the lifespan was investigated. In Chapter 5 we examine the effect of hunger state on the brain responses to food choice across the lifespan. In Chapter 6 we investigate the effect of hunger state and weight status on monetary reward processing. We finish this thesis with a general discussion of the results in Chapter 7