Biological, Psychiatric, Psychosocial, and Cognitive Factors of Poststroke Depression.

Background: Depression is the most common psychiatric condition that occurs after cerebrovascular accident, especially within the first year after stroke. Poststroke depression (PSD) may occur due to environmental factors such as functional limitations in daily activities, lower quality of life, or biological factors such as damage to areas in the brain involved in emotion regulation. Although many factors are hypothesized to increase the risk of PSD, the relative contribution of these factors is not well understood.

Barriers to Enrollment in Post-Stroke Brain Stimulation in a Racially and Ethnically Diverse Population.

Background And Purpose: Brain stimulation is an adjuvant strategy to promote rehabilitation after stroke. Here, we evaluated the influence of inclusion/exclusion criteria on enrollment in a transcranial direct current stimulation (tDCS) trial in the context of a racially/ethnically diverse acute stroke service at University of Texas Southwestern (UTSW).

Methods: 3124 (59.

Individual variability of cerebral autoregulation, posterior cerebral circulation and white matter hyperintensity.

Key Points: Cerebral autoregulation (CA) is a key mechanism to protect brain perfusion in the face of changes in arterial blood pressure, but little is known about individual variability of CA and its relationship to the presence of brain white matter hyperintensity (WMH) in older adults, a type of white matter lesion related to cerebral small vessel disease (SVD). This study demonstrated the presence of large individual variability of CA in healthy older adults during vasoactive drug-induced changes in arterial pressure assessed at the internal carotid and vertebral arteries. We also observed, unexpectedly, that it was the 'over-' rather than the 'less-reactive' CA measured at the vertebral artery that was associated with WMH severity.

Functional near-infrared spectroscopy maps cortical plasticity underlying altered motor performance induced by transcranial direct current stimulation.

Transcranial direct current stimulation (tDCS) of the human sensorimotor cortex during physical rehabilitation induces plasticity in the injured brain that improves motor performance. Bi-hemispheric tDCS is a noninvasive technique that modulates cortical activation by delivering weak current through a pair of anodal-cathodal (excitation-suppression) electrodes, placed on the scalp and centered over the primary motor cortex of each hemisphere. To quantify tDCS-induced plasticity during motor performance, sensorimotor cortical activity was mapped during an event-related, wrist flexion task by functional near-infrared spectroscopy (fNIRS) before, during, and after applying both possible bi-hemispheric tDCS montages in eight healthy adults.

Cerebral autoregulation of blood velocity and volumetric flow during steady-state changes in arterial pressure.

The validity of using transcranial Doppler measurement of cerebral blood flow velocity (CBFV) to assess cerebral autoregulation (CA) still is a concern. This study measured CBFV in the middle cerebral artery using transcranial Doppler and volumetric cerebral blood flow (CBF) in the internal carotid artery (ICA) using color-coded duplex ultrasonography to assess CA during steady-state changes in mean arterial pressure (MAP). Twenty-one healthy adults participated.

Wolf Motor Function Test for characterizing moderate to severe hemiparesis in stroke patients.

Objective: To extend the applicability of the Wolf Motor Function Test (WMFT) to describe the residual functional abilities of moderate to severely affected stroke patients.

Design: Data were collected as part of 2 double-blind, sham-controlled, randomized interventional studies: the Transcranial Direct Current Stimulation (tDCS) in Chronic Stroke Recovery and the tDCS Enhanced Stroke Recovery and Cortical Reorganization. Stroke patients were evaluated with the upper extremity Fugl-Meyer (UFM) and the WMFT in the same setting before treatment.

Functional imaging of intervention effects in stroke motor rehabilitation.

Objective: To assess intervention-specific effects on cortical reorganization after stroke as shown by available functional neuroimaging studies.

Data Sources: We searched Medline for clinical trials that contained the terms stroke, reorganization, and recovery, as well as either positron-emission tomography and PET, near-infrared spectroscopy and NIRS, single-photon emission tomography and SPECT, or functional magnetic resonance imaging and functional MRI; we reviewed primary and secondary references.

Study Selection: Articles that reported neuroimaging findings as a result of a specific treatment involving more than 1 subject were included.

MR compatible force sensing system for real-time monitoring of wrist moments during fMRI testing.

Functional magnetic resonance imaging (fMRI) of brain function is used in neurorehabilitation to gain insight into the mechanisms of neural recovery following neurological injuries such as stroke. The behavioral paradigms involving the use of force motor tasks utilized in the scanner often lack the ability to control details of motor performance. They are often limited by subjectiveness, lack of repeatability, and complexity that may exclude evaluation of patients with poor function.

Functional neuroimaging in motor recovery after stroke.

Neuroimaging techniques provide information on the neural substrates underlying functional recovery after stroke, the number one cause of long-term disability. Despite the methodological difficulties, they promise to offer insight into the mechanisms by which therapeutic interventions can modulate human cortical plasticity. This information should lead to the development of new, targeted interventions to maximize recovery.