Testing the structural disconnection hypothesis: Myelin content correlates with memory in healthy aging.

Introduction: The "structural disconnection" hypothesis of cognitive aging suggests that deterioration of white matter (WM), especially myelin, results in cognitive decline, yet in vivo evidence is inconclusive.

Methods: We examined age differences in WM microstructure using Myelin Water Imaging and Diffusion Tensor Imaging in 141 healthy participants (age 20-79). We used the Virginia Cognitive Aging Project and the NIH Toolbox® to generate composites for memory, processing speed, and executive function.

C-L Case Conference: Assessment of Dispositional Capacity in Medically Complex Patients.

We present the case of a 76-year-old male with mild cognitive impairment and delirium who was referred to consultation-liaison psychiatry for an assessment of capacity to choose discharge. Cases involving "dispositional capacity" are complex and increasingly frequent, with momentous consequences for patients and their families, but are rarely discussed in the literature. In this article, experts in functional assessment, cognition, and ethics provide guidance for this commonly encountered clinical scenario based on their experience and available literature.

Correlates of axonal content in healthy adult span: Age, sex, myelin, and metabolic health.

As the emerging treatments that target grey matter pathology in Alzheimer's Disease have limited effectiveness, there is a critical need to identify new neural targets for treatments. White matter's (WM) metabolic vulnerability makes it a promising candidate for new interventions. This study examined the age and sex differences in estimates of axonal content, as well the associations of with highly prevalent modifiable health risk factors such as metabolic syndrome and adiposity.

Metabolic syndrome and adiposity: Risk factors for decreased myelin in cognitively healthy adults.

Metabolic syndrome (MetS) is a cluster of conditions that affects ∼25% of the global population, including excess adiposity, hyperglycemia, dyslipidemia, and elevated blood pressure. MetS is one of major risk factors not only for chronic diseases, but also for dementia and cognitive dysfunction, although the underlying mechanisms remain poorly understood. White matter is of particular interest in the context of MetS due to the metabolic vulnerability of myelin maintenance, and the accumulating evidence for the importance of the white matter in the pathophysiology of dementia.

Structural and Functional Neuroanatomy of Core Consciousness: A Primer for Disorders of Consciousness Clinicians.

Understanding the structural and functional neuroanatomy of core consciousness (ie, wakefulness and awareness) is an asset to clinicians caring for persons with disorders of consciousness. This article provides a primer on the structural and functional neuroanatomy of wakefulness and awareness. The neuroanatomical structures supporting these elements of core consciousness functions are reviewed first, after which brief description of the clinically evaluable relationships between disruption of these structures and disorders of consciousness (ie, brain-behavior relationships) are outlined.

Psychiatric Screening Measures in Behavioral Variant Frontotemporal Dementia.

Objective: Behavioral variant frontotemporal dementia (bvFTD) is sometimes misdiagnosed as a primary psychiatric disorder, such as major depressive disorder, bipolar disorder, an anxiety disorder, autism spectrum disorder (ASD), or attention-deficit hyperactivity disorder (ADHD). Nonspecialists often use screening measures for primary psychiatric disorders in early assessments of persons with bvFTD. The investigators aimed to evaluate the manifestations of bvFTD in surveys intended to screen for primary psychiatric disorders.

Network Localization of Spontaneous Confabulation.

Objective: Spontaneous confabulation is a symptom in which false memories are conveyed by the patient as true. The purpose of the study was to identify the neuroanatomical substrate of this complex symptom and evaluate the relationship to related symptoms, such as delusions and amnesia.

Methods: Twenty-five lesion locations associated with spontaneous confabulation were identified in a systematic literature search.

The American Congress of Rehabilitation Medicine Diagnostic Criteria for Mild Traumatic Brain Injury.

Objective: To develop new diagnostic criteria for mild traumatic brain injury (TBI) that are appropriate for use across the lifespan and in sports, civilian trauma, and military settings.

Design: Rapid evidence reviews on 12 clinical questions and Delphi method for expert consensus.

Participants: The Mild Traumatic Brain Injury Task Force of the American Congress of Rehabilitation Medicine Brain Injury Special Interest Group convened a Working Group of 17 members and an external interdisciplinary expert panel of 32 clinician-scientists.

Machine learning classification of chronic traumatic brain injury using diffusion tensor imaging and NODDI: A replication and extension study.

Individuals with acute and chronic traumatic brain injury (TBI) are associated with unique white matter (WM) structural abnormalities, including fractional anisotropy (FA) differences. Our research group previously used FA as a feature in a linear support vector machine (SVM) pattern classifier, observing high classification between individuals with and without acute TBI (i.e.

Alternative Structure Models of the Traumatic Brain Injury Rehabilitation Needs Survey: A Veterans Affairs TBI Model Systems Study.

Objective: To explore the factor structure of the Rehabilitation Needs Survey (RNS).

Design: Secondary analysis of observational cohort study who were 5-years post-traumatic brain injury (TBI).

Setting: Five Inpatient Rehabilitation Facilities.

Transcranial direct current stimulation modulates working memory and prefrontal-insula connectivity after mild-moderate traumatic brain injury.

Persistent posttraumatic symptoms (PPS) may manifest after a mild-moderate traumatic brain injury (mmTBI) even when standard brain imaging appears normal. Transcranial direct current stimulation (tDCS) represents a promising treatment that may ameliorate pathophysiological processes contributing to PPS. We hypothesized that in a mmTBI population, active tDCS combined with training would result in greater improvement in executive functions and post-TBI cognitive symptoms and increased resting state connectivity of the stimulated region, i.

A Double-Blind Placebo-Controlled, Randomized Trial of Divalproex Sodium for Posttraumatic Irritability Greater Than 1 Year After Mild to Moderate Traumatic Brain Injury.

Objective: Posttraumatic irritability after traumatic brain injury (TBI) may become a chronic problem and contribute to impaired everyday function, either alone or in combination with alcohol use disorder. The authors hypothesized that divalproex sodium (VPA) would improve posttraumatic irritability and result in lessened alcohol use.

Methods: This randomized, placebo-controlled double-blind clinical trial recruited participants with an index TBI occurring 1 or more years prior to enrollment, a history of alcohol use disorder, and posttraumatic irritability corroborated by a knowledgeable informant.

The prevalence, characteristics, and psychiatric correlates of traumatic brain injury in incarcerated individuals: an examination in two independent samples.

Primary Objective: Identify the prevalence, characteristics, and psychological correlates of traumatic brain injury (TBI) among incarcerated individuals.

Research Design: Three aims: (1) Determine the prevalence and characteristics of TBI in 1469 adults incarcerated in Wisconsin state prisons (1064 men, 405 women); (2) Characterize the relationship between mild TBI and mental illness in a sub-sample of men and women; (3) Reproduce the findings from Aim 1 and Aim 2 in an independent sample of 1015 adults incarcerated in New Mexico state prisons (600 men, 415 women).

Methods And Procedures: Standardized TBI assessment with structured clinical interviews and self-report questionnaires.

Cannabis Use in a Cohort of Healthcare-Seeking United States Military Veterans With Persisting Symptoms After Mild Traumatic Brain Injury: Preliminary Observations.

Introduction: Cannabis products, including cannabidiol (CBD) and tetrahydrocannabinol (THC), are increasingly easy to procure and use across the United States. The 2018 National Survey on Drug Use and Health (NSDUH) reported a past-month cannabis use rate of 8.6% among adults 26 years of age or older in the U.

Rivastigmine Transdermal Patch Treatment for Moderate to Severe Cognitive Impairment in Veterans with Traumatic Brain Injury (RiVET Study): A Randomized Clinical Trial.

Cognitive impairment is common in veterans with histories of traumatic brain injury (TBI). Cholinergic deficits have been hypothesized as contributors to this impairment. We report the effects of cholinesterase inhibitor rivastigmine transdermal patch treatment in veterans with TBI and post-traumatic memory impairment.

Post-traumatic Confusional State: A Case Definition and Diagnostic Criteria.

In response to the need to better define the natural history of emerging consciousness after traumatic brain injury and to better describe the characteristics of the condition commonly labeled posttraumatic amnesia, a case definition and diagnostic criteria for the posttraumatic confusional state (PTCS) were developed. This project was completed by the Confusion Workgroup of the American Congress of Rehabilitation Medicine Brain Injury Interdisciplinary Special Interest group. The case definition was informed by an exhaustive literature review and expert opinion of workgroup members from multiple disciplines.

A randomized controlled trial of acceptance and commitment therapy for psychological distress among persons with traumatic brain injury.

Psychological distress is common in persons with traumatic brain injury (TBI) but treatments remain underdeveloped. This randomized controlled trial of Acceptance and Commitment Therapy (ACT) was designed to address this gap. Ninety-three persons with medically-documented complicated mild to severe TBI, normal-to-mildly impaired memory, and clinically significant psychological distress in the chronic phase of recovery were randomized to receive eight weeks of ACT (manualized with adaptations to address TBI-related cognitive impairments) or a single session of needs assessment, brief counseling/education, and referral.

Minimum Competency Recommendations for Programs That Provide Rehabilitation Services for Persons With Disorders of Consciousness: A Position Statement of the American Congress of Rehabilitation Medicine and the National Institute on Disability, Independent Living and Rehabilitation Research Traumatic Brain Injury Model Systems.

Persons who have disorders of consciousness (DoC) require care from multidisciplinary teams with specialized training and expertise in management of the complex needs of this clinical population. The recent promulgation of practice guidelines for patients with prolonged DoC by the American Academy of Neurology, American Congress of Rehabilitation Medicine (ACRM), and National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) represents a major advance in the development of care standards in this area of brain injury rehabilitation. Implementation of these practice guidelines requires explication of the minimum competencies of clinical programs providing services to persons who have DoC.

Establishment of a Patient-Centered Outcomes Research Network for Individuals with TBI and Neuropsychiatric Symptoms.

: The overarching goal of this project was to establish a group comprised of a variety of TBI stakeholders for the purpose of: (1) determining facilitators and barriers in management of neuropsychiatric symptoms after TBI; (2) identifying strategies for maintaining a TBI PCOR network; (3) enumerating research topics related to TBI neuropsychiatry; and (4) highlighting policy changes related to TBI neuropsychiatry.: Twenty-nine TBI stakeholders participated in focus group discussions. Qualitative analyses were conducted both manually and using Dedoose software.