For females, with improved understanding of regional brain activity during emotion processing, we maybe in a position to explain the neurobiology of increased vulnerability to depression. Finally, the measures employed in this work seem sensitive to variability in healthy people

and may therefore serve as endophenotypic markers of vulnerability Inhibitors,research,lifescience,medical to neuropsychiatrie disorders in which sex differences are evident and may contribute to developing genetic models. Selected abbreviations and acronyms BOLD blood oxygenation level-dependent CBF cerebral blood flow CSF cerebrospinal fluid CVLT California Verbal Learning Test fMRI functional magnetic resonance imaging GM gray matter WM white matter Inhibitors,research,lifescience,medical Notes Supported by NIH grants MH-43880 and MH-60722. We thank Wendy Snyder for assistance in preparation of the manuscript.
No single parameter completely, or even best, describes the functional status of the brain. Any measurement of brain “activity” subsumes a complex set of biochemical and physiological phenomena subserving diverse neuronal activities, such as cellular homeostasis, neuronal excitation and

inhibition, maintenance of membrane potentials, and plastic change at the cellular or subcellular level. The choice of which parameter to measure in a given study must Inhibitors,research,lifescience,medical be guided by the particular research question, and the use of multiple imaging methods Inhibitors,research,lifescience,medical to obtain information about several different parameters in the same patients is perhaps the most informative approach (Figure 1.). Figure 1 Positron emission tomography (PET) images in the same patient made with [18F]dihydroxyphenylalanine (F-DOPA) (left) showing high presynaptic concentrations primarily in the basal ganglia and H2 15O (right) showing high regional cerebral blood flow Inhibitors,research,lifescience,medical (rCBF) … Measures of general neuronal activity The idea of measuring regional cerebral blood flow (rCBF, with

positron emission tomography [PET] and IV H2 15O or inhaled 15O2 or C15O) or blood oxygenation level (with functional magnetic resonace imaging [fMRI]) to assess neural activity is well grounded in a firm theoretical base beginning with observations in the late 1800s that an augmented level of tissue function is sustained by increasing the rate Montelukast Sodium of oxygen consumption and, therefore, the flow of oxygenated blood to the tissue (in this case, brain). Because these parameters can be measured in less than a minute and repeatedly, they are well suited to delineating the cerebral concomitants of transient mental phenomena such as cognition and emotion. The brain’s MG-132 cost energy requirements, among the highest of any organ system, are normally provided by blood glucose.