Rapid cerebral hemodynamic modulation during attentional and executive tasks: a functional transcranial Doppler sonography study in patients with schizophrenia and healthy controls
Neurophysiology of executive function has been a central research activity of our group (Schuepbach et al., 2002; Schuepbach et al., 2007a) with a particular focus on schizophrenia (Schuepbach et al., 2007b). Among other results, we were able to delineate behaviourally specific (early) from non-specific (late) phases of rapid cerebral hemodynamic modulation in the MCA (lateral hemispheres) with an overlap with task accuracy of 63.9% in the left hemisphere (Schuepbach et al., 2007a). Using the excellent temporal resolution of functional transcranial Doppler sonography (fTCD), we now focus on the association between early rapid modulation of cerebral hemodynamics during planning and attentional/other executive tasks. The sample will consist of patients with chronic schizophrenia and age- and gender- matched healthy subjects. This project will use the brand new digital transcranial Doppler (Multi-Dop X, DWL, Singen, Germany) as provided by a grant from the University of Zurich to this research group. Localization of the MCAs will be easier, because there are 32 gates per transducer, all measuring a distinct signal at an individual depth and depicted in the so-called M-Mode. This project addresses important questions on the neurophysiological linkage between spatial planning and other attentional/executive tasks and also the brain behaviour relationship between rapid cerebral hemodynamic modulation and complex measures of behaviour.