title: Ageing diminishes the modulation of human brain responses to visual food cues by meal ingestion.
abstract: OBJECTIVE
  Rates of obesity are greatest in middle age. Obesity is associated with altered activity of brain networks sensing food-related stimuli and internal signals of energy balance, which modulate eating behaviour. The impact of healthy mid-life ageing on these processes has not been characterised. We therefore aimed to investigate changes in brain responses to food cues, and the modulatory effect of meal ingestion on such evoked neural activity, from young adulthood to middle age.
  
  
  METHODS
  Twenty-four healthy, right-handed subjects, aged 19.5-52.6 years, were studied on separate days after an overnight fast, randomly receiving 50 ml water or 554 kcal mixed meal before functional brain magnetic resonance imaging while viewing visual food cues.
  
  
  RESULTS
  Across the group, meal ingestion reduced food cue-evoked activity of amygdala, putamen, insula and thalamus, and increased activity in precuneus and bilateral parietal cortex. Corrected for body mass index, ageing was associated with decreasing food cue-evoked activation of right dorsolateral prefrontal cortex (DLPFC) and precuneus, and increasing activation of left ventrolateral prefrontal cortex (VLPFC), bilateral temporal lobe and posterior cingulate in the fasted state. Ageing was also positively associated with the difference in food cue-evoked activation between fed and fasted states in the right DLPFC, bilateral amygdala and striatum, and negatively associated with that of the left orbitofrontal cortex and VLPFC, superior frontal gyrus, left middle and temporal gyri, posterior cingulate and precuneus. There was an overall tendency towards decreasing modulatory effects of prior meal ingestion on food cue-evoked regional brain activity with increasing age.
  
  
  CONCLUSIONS
  Healthy ageing to middle age is associated with diminishing sensitivity to meal ingestion of visual food cue-evoked activity in brain regions that represent the salience of food and direct food-associated behaviour. Reduced satiety sensing may have a role in the greater risk of obesity in middle age.
authors: Diabetes Research Group, School of Medicine, King's College London, London, UK.
authors: Y S
authors: YS
authors: Cheah
authors: 1] Diabetes Research Group, School of Medicine, King's College London, London, UK [2] Centre for Neuroimaging Sciences, Institute of Psychiatry, King's College London, London, UK.
authors: S
authors: S
authors: Lee
authors: Diabetes Research Group, School of Medicine, King's College London, London, UK.
authors: G
authors: G
authors: Ashoor
authors: Diabetes Research Group, School of Medicine, King's College London, London, UK.
authors: Y
authors: Y
authors: Nathan
authors: 1] Centre for Neuroimaging Sciences, Institute of Psychiatry, King's College London, London, UK [2] Division of Brain Sciences, Centre for Mental Health, Imperial College London, London, UK.
authors: L J
authors: LJ
authors: Reed
authors: Centre for Neuroimaging Sciences, Institute of Psychiatry, King's College London, London, UK.
authors: F O
authors: FO
authors: Zelaya
authors: Centre for Neuroimaging Sciences, Institute of Psychiatry, King's College London, London, UK.
authors: M J
authors: MJ
authors: Brammer
authors: Diabetes Research Group, School of Medicine, King's College London, London, UK.
authors: S A
authors: SA
authors: Amiel
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology* / Q000523:psychology*; D001066:Appetite; D001069:Appetite Regulation; D001921:Brain / Q000503:physiopathology*; D003463:Cues; D004435:Eating; D005215:Fasting; D005260:Female; D005502:Food; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology; D010775:Photic Stimulation; D012527:Satiation