Glossary Terms  Home

H

Hemodynamic Response (HDR)

The change in MR signal on T2 images following local neuronal activity.  The hemodynamic response results from a decrease in the amount of deoxygenated hemoglobin present within a voxel.

Heteroscedastic

Having the property that the distributions of noise are different across experimental conditions.

Homogeneity

Uniformity over space and time. In the context of MRI, a homogeneous magnetic field is one that has the same strength throughout a wide region near the center of the scanner bore.

 

Homoscedastic

Having the property that the distributions of noise are similar for all experimental conditions.