Relative food preference and hedonic judgments in schizophrenia

There is a well-documented disruption of the neural network associated with reward evaluation in schizophrenia. This same system is involved in coding the incentive value of food in healthy individuals, but few studies to date have examined anhedonia and its relation to food hedonicity and preference in schizophrenia. Relative preference and hedonic food ratings were examined in schizophrenia patients and healthy controls. In the relative preference task, subjects viewed photographs of food items and selected the one that they most preferred. Hedonic ratings were obtained by asking subjects how much they liked the food stimulus on a scale of 1-5. There were no overall response time differences between the two groups in the relative preference task, but schizophrenia patients showed subtle differences in their hedonic ratings of foods compared with control subjects. Schizophrenia patients gave more positive hedonic ratings for food than did controls, and the use of fewer positive ratings was associated with increased anhedonia, particularly with loss of sexual interest. These results suggest that while making relative preference judgments may be intact, hedonic values attached to food may be altered in schizophrenia, and they may be related to dysfunction in more basic vegetative systems.