BOLD
Also written as: BOLD — Blood Oxygen Level-Dependent
MRI technique measuring brain activity through blood oxygen level-dependent signal changes.
Full Definition
Blood oxygen level-dependent (BOLD) imaging is a functional MRI technique that detects changes in brain activity by measuring alterations in blood oxygenation. When neurons become active, they consume oxygen, leading to local changes in the ratio of oxygenated to deoxygenated hemoglobin. These changes create subtle variations in magnetic susceptibility that can be detected by specialized MRI sequences. BOLD imaging forms the basis of functional MRI (fMRI) studies and is widely used in both research and clinical settings to map brain function, assess language lateralization, and evaluate motor areas before surgical procedures.
Usage
Usage note: Always capitalize as acronym; spell out on first use in formal documents.
In Context
- "The BOLD signal demonstrated activation in the motor cortex during the finger-tapping task." — fMRI study report
- "BOLD imaging protocols require careful attention to motion artifacts and temporal resolution." — Technical documentation