Individuals diagnosed with schizotypal personality disorder (SPD) exhibit patterns of cognitive deficits in (1) attention (Lees-Roitman, Cornblatt, Bergman, Obuchowski, Mitropoulou, Keefe, Silverman, & Siever, 1997), (2) memory (Bergman, Harvey, Lees-Roitman, Mohs, Margerm, Silverman, & Siever, 1998), (3) executive functioning (Cadenhead, Perry, Shafer, & Braff, 1999), and recently (4) neuromotor functioning (Neumann & Walker, 1999), similar to individuals with a diagnosis of schizophrenia. Furthermore, recent research suggests a link between neuromotor and cognitive functioning in schizophrenia spectrum disorders (SSDs) (Neumann & Walker, 2003). The current study is an extension of research on non-drug-induced neuromotor disturbances in individuals with SPD and examines how such disturbances covary with neurocognitive measures. Approximately thirty-three adults (18-65) were rated for SPD symptoms. Motor assessments included a computerized motor task and finger tapping test. Cognitive assessments included measures of attention, verbal and visual memory, and executive functioning. Consistent with previous research, the SPD group displayed significant right hand (left hemisphere) motor disturbances (i.e., increased force and force variability) compared to healthy controls after excluding all cases reporting a history of head injury. In addition, results indicate significant associations between motor, cognitive, and symptom variables. Consistent with previous research, neuromotor functioning and the relationships between motor and cognitive functioning varied as a function of Time of Day (TOD) of testing. Understanding the relationship between neuromotor and neurocognitive functioning may help elucidate the neural systems that contribute the symptoms characteristic of SSDs.
