Social network reductions are associated with negative symptoms in schizophrenia.

Background: A recent environmental systems theory of negative symptoms in schizophrenia (SZ) proposes a role for reductions in social networks that exist within microsystems (i.e., the contexts in which social interactions occur). However, it is unclear which aspects of social networks are most impacted in SZ and whether these are differentially associated with specific domains of negative symptoms. The current study aimed to address these gaps in the literature using a novel social network tool in combination with Ecological Momentary Assessment (EMA) and clinical ratings of negative symptoms.

Methods: Participants included 40 outpatients diagnosed with SZ and 35 demographically matched healthy controls (CN) who completed the sociogram, Brief Negative Symptom Scale (BNSS), and 7 days of EMA surveys assessing anhedonia, avolition, and asociality. ANOVAs examined group differences in social network characteristics. Correlations examined associations between social network characteristics and negative symptoms measured via the BNSS and EMA.

Results: Results indicated that: (1) SZ had greater social network reductions than CN, including lower: network density, number of microsystems, people in microsystems, connections across and within microsystems (p's < 0.05, d-value range 0.58 to 0.74); (2) these social network reductions were associated with greater severity of negative symptoms on the BNSS (r range - 0.28-0.34, p < .05) and asociality measured via EMA surveys (r's = - 0.24 to - 0.26, p's < 0.05).

Conclusions: Findings clarified the nature of social network dysfunction in SZ and identify novel targets for psychosocial interventions focused on modifying the number of social microsystems and the connections within/across these microsystems.