The rats on the junk food diet demonstrated impaired performance, taking substantially longer breaks than the lean rats before returning to the task.
In a 30-minute session, the overweight rats took breaks that were nearly twice as long as the lean ones.
These findings suggest that a pattern of consuming junk food, not just the occasional binge, is responsible for obesity and cognitive impairments, Blaisdell added in the research published in the journal Physiology and Behaviour.