Neuroimaging Advances in Deep Brain Stimulation: Review of Indications, Anatomy, and Brain Connectomics.

Deep brain stimulation is an established therapy for multiple brain disorders, with rapidly expanding potential indications. Neuroimaging has advanced the field of deep brain stimulation through improvements in delineation of anatomy, and, more recently, application of brain connectomics. Older lesion-derived, localizationist theories of these conditions have evolved to newer, network-based "circuitopathies," aided by the ability to directly assess these brain circuits in vivo through the use of advanced neuroimaging techniques, such as diffusion tractography and fMRI. In this review, we use a combination of ultra-high-field MR imaging and diffusion tractography to highlight relevant anatomy for the currently approved indications for deep brain stimulation in the United States: essential tremor, Parkinson disease, drug-resistant epilepsy, dystonia, and obsessive-compulsive disorder. We also review the literature regarding the use of fMRI and diffusion tractography in understanding the role of deep brain stimulation in these disorders, as well as their potential use in both surgical targeting and device programming.

Exercise of linguistic control by speakers in an adult day treatment program.

Ability of adults with mental retardation to exhibit linguistic "control" in informal settings within peer and staff dyads was evaluated. Results revealed that they produced significantly more utterances with staff than with peers in informal settings. However, they did not exhibit significant amounts of directives or questions, the two types of verbal control bids studied. Staff members used significantly more directives and questions as bids for control in non-peer settings than did the speakers with mental retardation in comparable peer interactions. Findings are consistent with observations of "learned helplessness" or prompt reliance within the population of persons with mental retardation. Results suggest that both staff members and adults with mental retardation have preconceived ideas on how to conduct themselves in daily interactions.