Studies of schizophrenic patients in psychotic and clinically remitted states and of biological relatives indicate that subtle anomalies in information processing may be critical components of neuropsychological vulnerability to schizophrenia. We describe a conception of possible abnormalities and several recent strategies to differentiate these possibilities. Within Continuous Performance Test conditions, varying the perceptual load vs. the active, working memory load yields a distinction between a stable vulnerability factor across clinical states and a potential mediating vulnerability factor. Specialized backward masking paradigms offer ways to separate two initial sensory-perceptual processes from attentional shifting processes. Top-down attentional influences on sensorimotor gating allow examination of the role of central executive processes in modulating early sensory processes. Initial results are discussed.