OBJECTIVE: Patients with schizophrenia show deficits in planning, and the Stockings of Cambridge (SOC) is a task that assesses planning performance. This study was undertaken to investigate rapid changes of cerebral hemodynamics during separate phases of SOC in schizophrenia and normals by means of functional transcranial Doppler sonography (fTCD). METHODS: We included 21 patients with chronic schizophrenia and a control group of 20 healthy subjects in the study. They underwent fTCD of the middle (MCA) and anterior cerebral arteries (ACA) during performance of SOC. RESULTS: The main finding was that healthy subjects significantly modulated the early cerebral hemodynamic response along distinct conditions of SOC, whereas we observed no significant differences in patients. Normally, there was an up-regulation of cerebral hemodynamics during mental planning, and about zero values were observed during movement execution. Patients showed lower development of the early cerebral hemodynamic response during planning of SOC. CONCLUSIONS: The findings of this study suggest a uniform pattern of cerebral hemodynamic regulation during a planning task in schizophrenia, whereas healthy subjects modulated such a response along a planning-movement execution sequence. SIGNIFICANCE: We provide novel evidence that modulation of cerebral hemodynamics is compromised in schizophrenia, and that fTCD constitutes a proper method to measure these alterations.