In acute schizophrenia, three syndromes: the active syndrome, the withdrawn syndrome, and the unreality syndrome, have been derived from a comprehensive clinical evaluation with the Present State Evaluation and the Brief Psychiatric Rating Scale (BPRS). Two of the syndromes were related to a behavioral and physiological activation dimension and associated with opposite patterns of hemispheric activation. The two factors having affinities with the active and withdrawn syndromes in schizophrenia would have identical patterns of cognitive asymmetry on the Warrington Recognition Memory Test (WRMT), and would be differentiated by arousal levels as measured with the Thayer Activation-Deactivation scales: Tension, Energy, Calmness, Tiredness. This chapter explains the etiological importance of hemispheric asymmetry in both schizotypy and schizophrenia through the relation disclosed between syndromes or personality factors and patterns of cognitive asymmetry, handedness, and gender.