Declarative memory and WCST-64 performance in subjects with schizophrenia and healthy controls.

The Wisconsin Card Sorting Test (WCST) is a set-switching task used extensively to study impaired executive functioning in schizophrenia. Declarative memory deficits have also been associated with schizophrenia and may affect WCST performance because continued correct responding depends on remembering the outcome of previous responses. This study examined whether performance in visual and verbal declarative memory tasks were associated with WCST performance.

Lack of relationship between acoustic startle and cognitive variables in schizophrenia and control subjects.

Measures of acoustic startle such as prepulse inhibition (PPI) and startle latency have been found to be impaired in schizophrenia, and are commonly thought to be related to cognitive deficits in this disease. However, findings about the relationship between startle variables and cognitive performance have been equivocal. In this study, we examined correlations between startle measures (baseline startle magnitude, latency, habituation and PPI) and cognitive performance (using the Benton Visual Retention Test, Conner's Continuous Performance Test, California Verbal Learning Test, Finger Tapping Test, and Wisconsin Card Sort Test) in 107 schizophrenia patients and 94 healthy controls.

Heritability of acoustic startle magnitude, prepulse inhibition, and startle latency in schizophrenia and control families.

Prepulse inhibition (PPI) is an acoustic startle paradigm that has been used as an operational measure of sensorimotor gating. Many patients with schizophrenia have impaired PPI, and several lines of evidence suggest that PPI may represent a heritable endophenotype in this disease. We examined startle magnitude and latencies in 40 schizophrenia patients, 58 first-degree relatives of these patients, and 100 healthy controls.