Does social defeat cause negative symptoms? A prospective study in a multi-national community sample.

Psychological models of the consequences of ostracism (i.e. being socially excluded and ignored) and negative symptoms in schizophrenia suggest that repeatedly experiencing ostracism can lead to elevated levels of amotivation, anhedonia, and asociality (i.e. negative symptoms). We tested this assumption in a prospective study, following up a large multi-national community sample from Germany, Indonesia, and the United States (N = 962) every four months over one year. At each of the four assessment points (T0 - T3), participants rated their recent ostracism experiences and negative symptoms. Using cross-lagged panel analyses we found a) that negative symptoms and experiences of ostracism were significantly associated in each of the four assessment points, b) that ostracism predicted negative symptoms over time (T2 to T3), and c) that negative symptoms increased ostracism (T0 to T1). The results are in line with the social defeat model of negative symptoms and suggest a bi-directional longitudinal relationship between ostracism and negative symptoms. Moving forward, it will therefore be important to gain an understanding of potential moderators involved in the mechanism.