Optical Imaging of Brain Function and Metabolism 2: Physiological Basis and Comparison to Other Functional Neuroimaging Methods (Advances in Experimental Medicine and Biology, 413)

This volume covers the latest developments in optical imaging of the brain which is becoming an increasingly important functional neuroimaging method. Optical intrinsic signals offer unrivaled temporal and spatial resolution of functional measurements of the exposed brain cortex in animals and humans. Near-infrared spectroscopy and imaging ap­ proaches permit the noninvasive functional assessment of the human brain at bedside. Main advantages of these optical techniques are the biochemical specificity of the meas­ urements and the potential of measuring correlates of intracellular and intravascular oxy­ genation simultaneously. Recent data indicate that one may also measure a more direct correlate of neuronal activity associated with changes in light scattering. In this volume, recent technical progress of the optical method is covered as well as the physiological basis of the measurements. In simultaneous studies, near-infrared spec­ troscopy measurements are directly compared to other functional methods, especially PET and fMRI and examples are given for new applications of the NIRS-method. Based on re­ sults obtained with optical methods and other functional techniques the latest in our under­ standing of the coupling of neuronal activity and cerebral blood flow response is reviewed. This is an important basis for a better understanding of all functional neuroi­ maging methods which rely on neurovascular coupling such as PET, SPET and fMRI. Fi­ nally the optical method is put into the perspective of presently available functional neuroimaging methods including fMRI, PET, MEG and EEG. Front Matter....Pages i-xi Functional Neuroimaging....Pages 1-18 Signal Sources in Bold Contrast FMRI....Pages 19-25 The MR T 1 Based Perfusion Model....Pages 27-34 Is There a Different Type of MR-Contrast in the Early Phase of Functional Activation?....Pages 35-42 Signal Sources in PET....Pages 43-51 Can We Measure Correlates of Neuronal Activity with Non-Invasive Optical Methods?....Pages 53-62 Measurement of Cytochrome Oxidase Redox State by Near Infrared Spectroscopy....Pages 63-73 Spatial Resolution Enhancement through Time Gated Measurements....Pages 75-83 Towards Near-Infrared Imaging of the Brain....Pages 85-89 Cerebral Oxygenation States as Revealed by Near-Infrared Spectrophotometry....Pages 91-96 Brain Oxygenation Monitoring during Cardiopulmonary Bypass by Near Infrared Spectroscopy....Pages 97-104 A Role for Near Infrared Spectroscopy in Psychiatry?....Pages 105-112 Near-Infrared Spectroscopy in Functional Activation Studies....Pages 113-127 Correlation between Absolute Deoxyhaemoglobin [dHb] Measured by Near Infrared Spectroscopy (NIRS) and Absolute R2′ as Determined by Magnetic Resonance Imaging (MRI)....Pages 129-137 Towards Brain Mapping Combining Near-Infrared Spectroscopy and High Resolution 3D MRI....Pages 139-147 Assessment of Local Brain Activation....Pages 149-153 Metabolic Aspects of Neurovascular Coupling....Pages 155-159 Metabolic Coupling during Activation....Pages 161-166 Neuronal-Vascular Coupling....Pages 167-176 Understanding Functional Neuroimaging Methods Based on Neurovascular Coupling....Pages 177-193 Dynamic NMR Studies of Perfusion and Oxidative Metabolism during Focal Brain Activation....Pages 195-203 Changes of Blood Flow and Oxygen Consumption in Visual Cortex of Living Humans....Pages 205-208 Uncoupling of Absolute CBF to Neural Activity....Pages 209-214 Vascular Regulation at Sub Millimeter Range....Pages 215-220 Linking Cerebral Blood Oxygenation to Human Brain Function....Pages 221-233 Intersubject Analysis of FMRI Data Using Spatial Normalization....Pages 235-240 What Do We Expect from Non-Invasive Functional Neuroimaging?....Pages 241-244 Back Matter....Pages 245-249 This volume, comprising the proceedings of an International Symposium on Optical Imaging and Metabolism, held in May 1995 in Berlin, covers recent technical progress of optical method as well as the physiological basis of the measurements. Simultaneous studies are used to compare near-infrared spectroscopy measurements with other functional methods, especially PET and fMRI. In addition, examples are given for new applications of the NIRS-method. Also reviewed is the latest information on the coupling of neuronal activity and cerebral blood flow response. Finally, the optical method is put into the perspective of presently available functional neuroimaging methods including fMRI, PET, MEG, and EEG. Annotation c. by Book News, Inc., Portland, Or Proceedings of an international symposium held in Berlin, Germany, May 1-2, 1995