What technique is used to reveal brain activity by comparing blood flow in successive MRI scans?

Functional MRI (fMRI) is the appropriate technique for revealing brain activity by comparing blood flow in successive MRI scans. This method depends on the principle that blood flow increases to neural regions that are more active during specific tasks or cognitive processes.

fMRI utilizes the BOLD (Blood Oxygen Level Dependent) contrast mechanism, which detects changes in blood oxygenation and flow that occur in response to neural activity. When a particular area of the brain is engaged, it consumes more oxygen, which leads to increased blood flow to that region. By taking rapid series of MRI scans, researchers can track this dynamic change over time and construct a map of brain activity corresponding to specific tasks or stimuli.

This technique provides insight into brain function in a non-invasive manner and is widely used in research and clinical settings, making it a fundamental tool in neuroscience for understanding the correlates of cognition and behavior.