There are two main classes of schizophrenia symptoms: positive (e.g., hallucinations and delusions) and negative (e.g., flat affect and poverty of speech). Research by Crow (1980, 1985) proposes that negative symptoms indicate irreversible structural brain abnormality and, therefore, unlike positive symptoms, may be less responsive to environmental factors. If Crow’s theory is correct, this might lead us to hypothesize that environmental factors associated with culture and ethnicity may have more of an impact on the expression of positive, rather than negative, symptoms. We aimed to test this hypothesis in the current study. Our sample consisted of 47 patients (16 Anglo, 17 Latino, and 14 African-American) diagnosed with schizophrenia. In line with Crow’s hypotheses, Analyses of Variance (ANOVAs) revealed ethnic differences in positive but not negative symptoms. These results suggest that efforts to target environmental and sociocultural factors may be more effective in reducing positive than negative symptoms.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication, with the work [SPECIFY PERIOD OF TIME] after publication simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgment of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).