Seeking progress in disease modification in Parkinson disease.

Objective: Disease modification in Parkinson disease (PD) has remained an elusive goal, in spite of large investments over several decades. Following a large meeting of experts, this review article discusses the state of the science, possible reasons for past PD trials' failures to demonstrate disease-modifying benefit, and potential solutions.

Methods: The National Institute of Neurological Disorders and Stroke (NINDS) convened a meeting including leaders in the field and representatives of key stakeholder groups to discuss drug therapy with the goal of disease modification in PD.

A Common Function of Basal Ganglia-Cortical Circuits Subserving Speed in Both Motor and Cognitive Domains.

Distinct regions of the frontal cortex connect with their basal ganglia and thalamic counterparts, constituting largely segregated basal ganglia-thalamo-cortical (BTC) circuits. However, any common role of the BTC circuits in different behavioral domains remains unclear. Indeed, whether dysfunctional motor and cognitive BTC circuits are responsible for motor slowing and cognitive slowing, respectively, in Parkinson's disease (PD) is a matter of debate.

Executive attention deficits after traumatic brain injury reflect impaired recruitment of resources.

Deficits in attention are a common and devastating consequence of traumatic brain injury (TBI), leading to functional impairments, rehabilitation barriers, and long-term disability. While such deficits are well documented, little is known about their underlying pathophysiology hindering development of effective and targeted interventions. Here we evaluate the integrity of brain systems specific to attentional functions using quantitative assessments of electroencephalography recorded during performance of the Attention Network Test (ANT), a behavioral paradigm that separates alerting, orienting, and executive components of attention.

Isolation Syndrome after Cardiac Arrest and Therapeutic Hypothermia.

Here, we present the first description of an isolation syndrome in a patient who suffered prolonged cardiac arrest and underwent a standard therapeutic hypothermia protocol. Two years after the arrest, the patient demonstrated no motor responses to commands, communication capabilities, or visual tracking at the bedside. However, resting neuronal metabolism and electrical activity across the entire anterior forebrain was found to be normal despite severe structural injuries to primary motor, parietal, and occipital cortices.

Quantifying Poststroke Apathy With Actimeters.

The authors tested the hypothesis that wrist-worn actimeters can quantify the severity of poststroke apathy. The authors studied 57 patients admitted to an acute rehabilitation unit for ischemic or hemorrhagic stroke. After accounting for motor deficit of the affected arm and accounting for age, each increment of the Apathy Inventory score correlated with 5.

Natural History of Poststroke Apathy During Acute Rehabilitation.

To better understand the natural history of poststroke apathy, the authors tested 96 patients undergoing acute rehabilitation for stroke using the Apathy Inventory. A total of 28% of patients had apathy. Their Apathy Inventory scores improved a mean of 1 point by week 2 and 2 points by week 3, with the majority of patients remaining apathetic at discharge.

Post-stroke apathy and hypersomnia lead to worse outcomes from acute rehabilitation.

Apathy and hypersomnia occur after stroke and, by definition, reduce participation in rehabilitation, but their effect on outcome from acute rehabilitation is not known. We performed a retrospective review of 213 patients admitted to a stroke-specialized acute rehabilitation unit in the United States. All patients had ischemic or hemorrhagic stroke, and no dementia or dependence on others pre-stroke.

Common resting brain dynamics indicate a possible mechanism underlying zolpidem response in severe brain injury.

Zolpidem produces paradoxical recovery of speech, cognitive and motor functions in select subjects with severe brain injury but underlying mechanisms remain unknown. In three diverse patients with known zolpidem responses we identify a distinctive pattern of EEG dynamics that suggests a mechanistic model. In the absence of zolpidem, all subjects show a strong low frequency oscillatory peak ∼6-10 Hz in the EEG power spectrum most prominent over frontocentral regions and with high coherence (∼0.

Consciousness: its neurobiology and the major classes of impairment.

Human consciousness requires brainstem, basal forebrain, and diencephalic areas to support generalized arousal, and functioning thalamocortical networks to respond to environmental and internal stimuli. Disconnection of these interconnected systems, typically from cardiac arrest and traumatic brain injury, can result in disorders of consciousness. Brain injuries can also result in loss of motor output out of proportion to consciousness, resulting in misdiagnoses.

What is the role of brain mechanisms underlying arousal in recovery of motor function after structural brain injuries?

Purpose Of Review: Standard neurorehabilitation approaches have limited impact on motor recovery in patients with severe brain injuries. Consideration of the contributions of impaired arousal offers a novel approach to understand and enhance recovery.

Recent Findings: Animal and human neuroimaging studies are elucidating the neuroanatomical bases of arousal and of arousal regulation, the process by which the cerebrum mobilizes resources.

Determination of awareness in patients with severe brain injury using EEG power spectral analysis.

Objective: To determine whether EEG spectral analysis could be used to demonstrate awareness in patients with severe brain injury.

Methods: We recorded EEG from healthy controls and three patients with severe brain injury, ranging from minimally conscious state (MCS) to locked-in-state (LIS), while they were asked to imagine motor and spatial navigation tasks. We assessed EEG spectral differences from 4 to 24 Hz with univariate comparisons (individual frequencies) and multivariate comparisons (patterns across the frequency range).

Increased midbrain gray matter in Tourette's syndrome.

Objective: To investigate cerebral structure in Tourette's syndrome (TS).

Methods: Voxel-based morphometry study of high-resolution MRIs in 31 TS patients compared with 31 controls.

Results: Increased gray matter mainly in the left mesencephalon in 31 TS patients.

Regional cerebral blood flow correlates of the severity of writer's cramp symptoms.

Unlabelled: Writer's cramp is a type of idiopathic focal dystonia with incompletely understood pathophysiology. Recent studies provide evidence that one element might be a sensory processing defect. We performed a PET study with O(15) H(2)O to find out in which brain areas activity correlates with the severity of writer's cramp symptoms.