Food strikes obese women with learning impairment

In what could result in specific behavioural interventions to treat obesity, researchers have found that obese women are better able to identify cues that predict monetary rewards than those that predict food rewards.

"What we observed is not a learning impairment, but rather a food-specific impairment present only in obese female participants," said Ifat Levy from Yale School of Medicine at Yale University in the US.

The researchers examined how 133 normal-weight and obese men and women learn associations between cues and rewards.

Participants saw two coloured squares. One colour was sometimes followed by an image of a reward; the other colour was never followed by a reward. At some point, these contingencies switched - the second colour was followed by a reward, while the first was not.

The researchers found the obese women who performed the task with food rewards were impaired at learning and could not predict food rewards like they could predict the money rewards.

The study appeared in the journal Current Biology.