Familiarity preference in schizophrenia is associated with ambivalent attitudes towards others

Preferences or attitudes towards others are often shaped through implicit memory processes, and they serve a critical function in our social lives. Preferences driven by implicit familiarity (mere exposure effect) are particularly important when making judgments about others and forming attitudes of liking and social interaction. In schizophrenia, little is known about the effect of familiarity preference on judgments and attitudes toward others.

Subjects included 79 patients with a diagnosis of schizophrenia or schizoaffective disorder and 61 non-patient control subjects. Familiarity preference and trait judgments about others were assessed using a computer task in which neutral faces were rated on positive and negative character traits. "Attractiveness" was rated twice at the beginning and at the end, to measure familiarity preference. Clinical ratings were also obtained.

Patients and controls both demonstrated a positive familiarity preference effect. However, the groups differed on the predictive value of familiarity preference for trait judgments. In both groups, the presence of a familiarity preference effect predicted greater positive trait judgments. In patients only, the presence of a familiarity preference effect also predicted, although the correlation was less significant, greater negative trait judgments.

The findings are consistent with a preserved familiarity preference effect in individuals with schizophrenia and that the effect is primarily associated with changes in positive attitudes. However, in individuals with schizophrenia this effect is also linked with inferences about negative traits, resulting in ambivalence towards others. This finding may contribute to the impaired social functioning of people with schizophrenia.