Brain responses to anticipation and consumption of beer with and without alcohol

Abstract

Beer is a popular alcoholic beverage worldwide. Nonalcoholic beer (NA-beer) is increasingly marketed. Brain responses to beer and NA-beer have not been compared. It could be that the flavor of beer constitutes a conditioned stimulus associated with alcohol reward. Therefore, we investigated whether oral exposure to NA-beer with or without alcohol elicits similar brain responses in reward-related areas in a context where regular alcoholic beer is expected. Healthy men (n = 21) who were regular beer drinkers were scanned using functional MRI. Participants were exposed to word cues signaling delivery of a 10-mL sip of chilled beer or carbonated water (control) and subsequent sips of NA-beer with or without alcohol or water (control). Beer alcohol content was not signaled. The beer cue elicited less activation than the control cue in the primary visual cortex, supplementary motor area (reward-related region) and bilateral inferior frontal gyrus/frontal operculum. During tasting, there were no significant differences between the 2 beers. Taste activation after swallowing was significantly greater for alcoholic than for NA-beer in the inferior frontal gyrus/anterior insula and dorsal prefrontal cortex (superior frontal gyrus). This appears to be due to sensory stimulation by ethanol rather than reward processing. In conclusion, we found no differences in acute brain reward upon consumption of NA-beer with and without alcohol, when presented in a context where regular alcoholic beer is expected. This suggests that in regular consumers, beer flavor rather than the presence of alcohol is the main driver of the consumption experience.