John E. Desmond, Ph.D., M.S.

The Neuroimaging and Modulation Lab (NIMLAB), directed by Dr. John E. Desmond, is part of the Cognitive Neuroscience Division of the Department of Neurology at the Johns Hopkins University School of Medicine.

The laboratory investigates neural correlates of cognition and behavior using neuroimaging methods such as functional magnetic resonance imaging (fMRI) and neuromodulation techniques such as transcranial magnetic stimulation (TMS).

Research:

• The contributions of the cerebellum, and cerebro-cerebellar circuits, to cognition. The cerebellum has traditionally been viewed as a structure involved in motor coordination. However, neuroimaging and patient studies have revealed unexpected cerebellar involvement in cognitive performance beyond motor behavior. We are specifically interested in cerebellar contributions to verbal working memory performance.
• How aging in humans affects neural systems that are important for associative memory. These investigations pay special attention to two systems particularly important for classical conditioning, the medial temporal lobe and the cerebellum. The implications of this research are that simple eyeblink conditioning procedures may provide reliable indications of the integrity of cerebellar and medial temporal lobe structures. Such indications could be particularly useful for assessing brain dysfunction in disorders such as Alzheimer's Disease.
• Integration of transcranial magnetic stimulation with functional MRI. TMS and fMRI are complementary methods, because fMRI can reveal which regions of the brain activate during a cognitive task, whereas TMS can assess which of those activations are necessary for performance.
• Clinical applications of functional MRI, including characterization of altered brain activation due to disease, surgical planning, and diagnosis. An important aspect of fMRI for clinical purposes is that it is powerful enough to assess brain activations at the level of the individual patient as well as at the group level.
• Methodological aspects of functional MRI, such as estimating statistical power for group analyses. Such information can be used for designing neuroimaging studies with the appropriate sample size for detecting significant differences between conditions, or significant differences between populations of subjects.

Neuroimaging and Modulation Laboratory