Which neuroimaging modality offers high spatial resolution and measures hemodynamic responses?

Which neuroimaging modality offers high spatial resolution and measures hemodynamic responses?

• A. PET
• B. fMRI
• C. EEG
• D. CT

Answer: (B)

Functional neuroimaging that links neural activity to a physiological signal and can localize it precisely is what this asks about. The modality that provides high spatial resolution and measures hemodynamic responses is fMRI. It detects changes in blood flow and blood oxygenation that accompany neural activity—the BOLD signal—giving millimeter-scale localization of active regions. PET does measure metabolic activity, which is related to brain function, but its spatial resolution is lower than fMRI and it doesn’t track real-time hemodynamic changes as directly. EEG records electrical activity with excellent timing but relatively poor spatial localization and does not measure hemodynamics. CT is mainly used for structural imaging and, even with perfusion techniques, does not offer the same combination of high spatial resolution and functional hemodynamic measurement as fMRI.

Functional neuroimaging that links neural activity to a physiological signal and can localize it precisely is what this asks about. The modality that provides high spatial resolution and measures hemodynamic responses is fMRI. It detects changes in blood flow and blood oxygenation that accompany neural activity—the BOLD signal—giving millimeter-scale localization of active regions.

PET does measure metabolic activity, which is related to brain function, but its spatial resolution is lower than fMRI and it doesn’t track real-time hemodynamic changes as directly. EEG records electrical activity with excellent timing but relatively poor spatial localization and does not measure hemodynamics. CT is mainly used for structural imaging and, even with perfusion techniques, does not offer the same combination of high spatial resolution and functional hemodynamic measurement as fMRI.