Lunch at a restaurant with friends reduces cognitive control more than lunch eaten alone at a desk does, according to researchers from the Humboldt University at Berlin, Germany, and colleagues from other institutions.
Participants in the study either ate a solitary meal alone at their desk in a restricted amount of time, or took a short walk to a restaurant for an hour-long lunch with a friend.
All meals were identical in the kind and amounts of food consumed. After the meal, people who had a restaurant lunch were calmer and less wakeful than those who ate at their desks.
Since the meals differed in many ways including the presence of a friend, environment and lack of time restrictions, the authors explained, "It is impossible to specify at this point, which of the variables above are crucial for the effects observed in our study."
"Reduced cognitive control is a disadvantage when close self-monitoring of performance and detailed attention to errors is required, such as in numerical processing," the authors reported in the journal PLOS ONE.
"In other situations, an attenuation of cognitive control may be advantageous, such as when social harmony or creativity is desired," they said.