The Physiological Processes Underpinning PET and fMRI Techniques With an Emphasis on the Temporal and Spatial Resolution of These Methods

Abstract

In this paper the scanning techniques of PET and fMRI are presented and discussed in technical terms. The main focus of this paper is the physiological processes underpinning these techniques and the ways they operate temporally and spatially. Physiological processes captured by these techniques refer generally to the volume of blood in the brain and the concentration of oxygen in the blood. Temporal and spatial resolution in the case of these methods refers to data collection when the brain is scanned. Temporal resolution records the exact time when a cognitive process takes place; spatial resolution demonstrates in what part of the brain such activity takes place. A comparison between these two techniques shows that one needs the other in terms of measuring the blood and oxygen in the brain so clear pictures of cognitive processes and their locations to be obtained. Both PET and fMRI are in use from cognitive neuroscience, for through the measures that they take from the brain, cognitive processes and their locations can be clearly identified and read

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