Reliability of fMRI motor tasks in structures of the corticostriatal circuitry: implications for future studies and circuit function.

The corticostriatal circuits are important information processing networks. There is evidence that these circuits may be dysfunctional in a variety of neuropsychiatric conditions ranging from Parkinson's disease to bipolar disorder. Cross-sectional fMRI studies may clarify normal circuit function, and longitudinal studies may provide information on changes related to age in control subjects, as well as illness progression and treatment response in patient groups.

An fMRI motor activation paradigm demonstrates abnormalities of putamen activation in females with panic disorder.

Background: The neurobiology of panic disorder is incompletely understood. The aim of this study was to determine if functional abnormalities of the putamen occur in panic disorder.

Methods: Activation patterns of 12 female subjects with panic disorder were compared to 18 female healthy controls using functional MRI at 3 T.

Putamen coactivation during motor task execution.

Models of corticostriatal motor circuitry have focused on the role of the circuit in the hemisphere of the motor cortex providing primary control (contralateral to the movement). We used functional magnetic resonance imaging and functional connectivity analyses to study circuit function in both the controlling and noncontrolling hemispheres. During the completion of a unilateral motor task with either hand, each putamen nucleus demonstrated strong coactivation with structures in both hemispheres.

Motor deactivation in the human cortex and basal ganglia.

We used a functional magnetic resonance imaging motor activation paradigm for both hands and functional connectivity analyses to investigate motor deactivation. These analyses revealed ipsilateral (to the task) postcentral gyrus connectivity with the ipsilateral primary motor cortex as well as contralateral cerebellum for both hands. Analyses using default-mode network nodes as seed regions revealed connectivity patterns similar to previous studies of the default network and therefore provide evidence that this network is demonstrable using a synchronized motor activation paradigm.

Clinical characteristics and health service use of veterans with comorbid bipolar disorder and PTSD.

Objective: This study aimed to increase the understanding of the clinical characteristics and utilization of health services among veterans with comorbid bipolar disorder and posttraumatic stress disorder (PTSD).

Methods: A retrospective chart review was conducted that examined the clinical and health service use data of 139 male veterans with bipolar disorder (N=49), PTSD (N=49), or comorbid bipolar disorder and PTSD (N=41) who obtained services over two years from the Department of Veterans Affairs Salt Lake City Health Care System.

Results: Compared with patients with bipolar disorder or those with PTSD alone, those with both conditions had significantly higher mean Clinical Global Impression-Severity scores and required more frequent inpatient psychiatric treatment.