The relation of 2D:4D digit ratios with theory of mind and empathy in schizophrenia

Objective: As hand's second and fourth digit fingers (2D:4D) are one of the new areas studied in schizophrenia, 2D:4D ratio is known to be increased in schizophrenia patients. Studies resulted in a way that theory of mind and empathic abilities were worse in schizophrenia patients compared to healthy participants. Yet, these areas have not been combined in schizophrenia studies. The aim of this study is to investigate 2D:4D, the impairments of theory of mind, empathic abilities; the relation of 2D:4D finger lengths with theory of mind and empathy in schizophrenia. Method: The study was carried out with the sample consisted of 48 healthy participants and 48 patients diagnosed with schizophrenia according to DSM IV. The patients were assessed with Positive and Negative Syndrome Scale (PANSS), Empathy Quotient (EQ), Reading Mind in the Eyes Test (RMET) and digital caliper was used to measure 2D:4D finger lengths. Results: Statistical significance was found between patients and controls regarding empathy and theory of mind. When 2D:4D finger lengths were studied compared to healthy participants, schizophrenia patients also showed statistically significant results. Conclusions: Theory of mind and empathic abilities of schizophrenia patients show impairments compared to healthy participants. Schizophrenia patients also have increased left 2D:4D finger lengths. No correlation was found between 2D:4D, theory of mind and empathy. Key Words: Schizophrenia, 2D:4D digit ratio, empathy, theory of mind