Modalities of Magnetic Resonance Imaging (MRI)

The Brain Imaging Lab uses four types, or modalities, of MRI. Each modality captures information — usually in the form of images — about a particular dimension of either the structure or the functioning of the human brain. Taken together, the information from these modalities of MRI can provide a comprehensive picture of the brains of subjects in our studies. In addition to research on neuropsychiatric disorders, much of our work focuses on finding ways to increase the accuracy of individual modalities. We are also developing ways to combine information from multiple modalities in order to reveal new and important details about how the brain works, both in health and in illness.

Anatomical MRI is used to image the anatomical structures within the brain, such as the cortex, amygdala, or hippocampus. By measuring changes in the shape and volume of regions of the brain, we can identify anatomical abnormalities that are associated with specific neuropsychiatric illnesses.

Functional MRI (fMRI) tracks neural activity within the brain during performance of tasks that are designed to stimulate or inhibit that activity. By tracking differences in neural activity between groups, we can detect distinct abnormalities in the way that the brain functions in individuals with a particular disorder.

Diffusion Tensor Imaging (DTI) can be used to trace the anatomical connections between various regions of the brain. These connections lie within the white matter of the brain and allow for the coordinated functioning of multiple brain regions. Disruption of these anatomical connections will in turn disrupt coordinated functioning between brain regions.

Magnetic Resonance Spectroscopy (MRS) measures the distribution and concentration of metabolites in either the whole brain or in specific regions. MRS can be used to detect changes in the levels of metabolites that have been associated with illnesses such as depression, anxiety disorders, and ADHD.