Deeper into schizotypy and motor performance: Investigating the nature of motor control in a non-psychiatric sample

• A new quantitative method is developed to investigate the nature of motor control.
• Non-psychiatric schizotypes are compared to control participants.
• Schizotypes produce lines with greater psychomotor dyscontrol than controls.
• Schizotypes produce lines with lower sinusoidal frequencies than controls.
• Effects may result from poorer self-monitoring or non-adherence to motor principles.

Numerous studies have demonstrated that motor control deficits are characteristic of patients diagnosed with schizophrenia and those at-risk for the development of the disorder. Recent advances in the quantification of motor dysfunction have confirmed this, but these methods fail to consider an important aspect of subject performance: the qualitative nature of their psychomotor dyscontrol. We report on a novel technique used to quantify the qualitative nature of psychomotor performance and its relation to schizotypy. Control (n=35) and schizotypic subjects (n=47) completed a line-drawing task that yields metrics for psychomotor control and predominant frequency. Schizotypes evidenced greater psychomotor dyscontrol and lower predominant frequencies than controls. These results are interpreted as evidence of reduced visual-motor integration, self-monitoring capacity, or adherence to basic motor principles in schizotypes. The potential use of these metrics as putative endophenotypes for the liability for schizophrenia and the implications of these findings for the relationship between schizophrenia and schizotypy are discussed.