Tasting a liquid meal after a prolonged fast is associated with preferential activation of the left hemisphere.
We used positron emission tomographic scanning of the brain and measures of regional cerebral blood flow to investigate the response of 44 right-handed people to the oral administration of 2 ml of a liquid formula meal after a 36 h fast (and shortly before the administration of a satiating amount of the same meal). Several areas of the left hemisphere were significantly more activated than the contralateral, including the frontal operculum, ventral insula, and piriform cortex. In contrast with reports of right-hemisphere dominance in chemosensory perception in non-hungry individuals, our study reveals a preferential activation of the left hemisphere when people who are very hungry are briefly exposed to the chemical and physical properties of a liquid meal. This raises the possibility that the physiological context in which perception takes place (i.e. extreme vs moderate vs no hunger) may importantly affect the brain representation of chemosensory stimuli.
Del Parigi
Angelo
A
Obesity, Diabetes and Energy Metabolism Unit, Clinical Diabetes and Nutrition Section, NIDDK-NIH, 4212 North 16th Street, Phoenix, AZ 85016, USA.
Chen
Kewei
K
Salbe
Arline D
AD
Gautier
Jean-François
JF
Ravussin
Eric
E
Reiman
Eric M
EM
Tataranni
P Antonio
PA
D000328:Adult; D000679:Amygdala / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology; D002628:Chemoreceptor Cells / Q000502:physiology*; D004435:Eating / Q000502:physiology*; D005260:Female; D005508:Food Deprivation / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009833:Olfactory Pathways / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D012903:Smell / Q000502:physiology*; D013649:Taste / Q000502:physiology*; D014055:Tomography, Emission-Computed