Publications by authors named "Jordan H Grafman"

Article Synopsis
  • * Analysis of three datasets revealed a 'PTSD circuit' involving the medial prefrontal cortex, amygdala, and anterolateral temporal lobe, especially in veterans with traumatic brain injuries.
  • * Functional connectivity within this circuit was linked to PTSD symptoms and decreased after transcranial magnetic stimulation, suggesting it could be a key focus for future treatment trials.
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Background: Mild traumatic brain injury (mTBI) can result in lasting brain damage that is often too subtle to detect by qualitative visual inspection on conventional MR imaging. Although a number of FDA-cleared MR neuroimaging tools have demonstrated changes associated with mTBI, they are still under-utilized in clinical practice.

Methods: We investigated a group of 65 individuals with predominantly mTBI (60 mTBI, 48 due to motor-vehicle collision, mean age 47 ± 13 years, 27 men and 38 women) with MR neuroimaging performed in a median of 37 months post-injury.

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Objective: The long-term consequences of traumatic brain injury (TBI) on brain structure remain uncertain. Given evidence that a single significant brain injury event increases the risk of dementia, brain-age estimation could provide a novel and efficient indexing of the long-term consequences of TBI. Brain-age procedures use predictive modeling to calculate brain-age scores for an individual using structural magnetic resonance imaging (MRI) data.

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  • Transcranial magnetic stimulation (TMS) and deep brain stimulation (DBS) show potential in treating anxiety but lack a standardized method for identifying new targets.
  • Researchers found a common brain circuit linked to anxiety through various experiments, revealing that specific TMS and lesion sites influenced anxiety levels.
  • The study indicates that different brain circuit connections can predict changes in anxiety and highlights a new method for finding targeted treatments across various neuropsychiatric disorders.
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Introduction: Epidemiological studies report an association between traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) and clinically diagnosed Alzheimer's disease (AD). We examined the association between TBI/PTSD and biomarker-defined AD.

Methods: We identified 289 non-demented veterans with TBI and/or PTSD and controls who underwent clinical evaluation, cerebrospinal fluid (CSF) collection, magnetic resonance imaging (MRI), amyloid beta (Aβ) and tau positron emission tomography, and apolipoprotein E testing.

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Drug addiction is a public health crisis for which new treatments are urgently needed. In rare cases, regional brain damage can lead to addiction remission. These cases may be used to identify therapeutic targets for neuromodulation.

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Damage to specific brain circuits can cause specific neuropsychiatric symptoms. Therapeutic stimulation to these same circuits may modulate these symptoms. To determine whether these circuits converge, we studied depression severity after brain lesions (n = 461, five datasets), transcranial magnetic stimulation (n = 151, four datasets) and deep brain stimulation (n = 101, five datasets).

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Article Synopsis
  • The study aimed to understand the relationship between genetic expansions, age at onset, and syndromic differences in frontotemporal lobar degeneration (FTLD) using a large European sample.
  • Researchers found that pathogenic expansions were more common in patients with behavioral variant frontotemporal dementia (bvFTD) compared to primary progressive aphasia (PPA), and there were notable differences based on genetic ancestry.
  • The findings suggest a link between genetic factors, ancestry, and the development of bvFTD, highlighting the complexity of genetic risk associated with this condition.
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Brain lesions can provide unique insight into the neuroanatomical substrate of human consciousness. For example, brainstem lesions causing coma map to a specific region of the tegmentum. Whether specific lesion locations outside the brainstem are associated with loss of consciousness (LOC) remains unclear.

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Approximately 1.1 million family members are primary caregivers to post 9/11 veterans. These military caregivers assume a role that requires a long-term commitment that may affect their own health status; however, the impact on health among military caregivers is underestimated and underrepresented.

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Objective: To examine the association between traumatic brain injury (TBI) severity; social, family, and community reintegration outcomes; and return to work status among post-9/11 veterans in Department of Veterans Affairs (VA) care.

Design: Retrospective observational cohort study.

Setting: Mail/online survey fielded to a national sample of veterans.

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A common finding in human functional brain-imaging studies is that damage to neural systems paradoxically results in enhanced functional connectivity between network regions, a phenomenon commonly referred to as 'hyperconnectivity'. Here, we describe the various ways that hyperconnectivity operates to benefit a neural network following injury while simultaneously negotiating the trade-off between metabolic cost and communication efficiency. Hyperconnectivity may be optimally expressed by increasing connections through the most central and metabolically efficient regions (i.

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Objective: We compared performance on tests of dysexecutive behaviour (DB) and executive function (EF) in patients with behavioural variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA) and corticobasal syndrome (CBS).

Methods: Patients diagnosed with bvFTD (n=124), PPA (n=34) and CBS (n=85) were recruited. EF was measured with the Delis-Kaplan Executive Function System (DKEFS: performance based), and DB was measured with the Frontal Systems Behavior Scale (FrSBe: caregiver-report based).

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Accumulating neuroscience evidence indicates that human intelligence is supported by a distributed network of frontal and parietal regions that enable complex, goal-directed behaviour. However, the contributions of this network to social aspects of intellectual function remain to be well characterized. Here, we report a human lesion study (n = 144) that investigates the neural bases of social problem solving (measured by the Everyday Problem Solving Inventory) and examine the degree to which individual differences in performance are predicted by a broad spectrum of psychological variables, including psychometric intelligence (measured by the Wechsler Adult Intelligence Scale), emotional intelligence (measured by the Mayer, Salovey, Caruso Emotional Intelligence Test), and personality traits (measured by the Neuroticism-Extraversion-Openness Personality Inventory).

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Objective: To examine the association of epilepsy with traumatic brain injury (TBI) in Afghanistan and Iraq (Operation Enduring Freedom [OEF]/Operation Iraqi Freedom [OIF]) Veterans.

Design: Cross-sectional observational study.

Participants: A total 256 284 OEF/OIF Veterans who received inpatient and outpatient care in the Veterans Health Administration in fiscal years 2009-2010.

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Objective: This study evaluated whether structural brain lesions modulate the relationship between pathological aggression and the dopaminergic system in traumatic brain injury (TBI). While converging evidence suggests that different areas of the prefrontal cortex modulate dopaminergic activity, to date no evidence exists of a modulation of endogenous dopaminergic tone by lesion localization in penetrating TBI (pTBI).

Methods: This study included 141 male Caucasian veterans who suffered penetrating pTBI during their service in Vietnam and 29 healthy male Caucasian Vietnam veterans.

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We previously demonstrated with functional magnetic resonance imaging (fMRI) that religious belief depends upon three cognitive dimensions, which can be mapped to specific brain regions. In the present study, we considered these co-activated regions as nodes of three networks each one corresponding to a particular dimension, corresponding to each dimension and examined the causal flow within and between these networks to address two important hypotheses that remained untested in our previous work. First, we hypothesized that regions involved in theory of mind (ToM) are located upstream the causal flow and drive non-ToM regions, in line with theories attributing religion to the evolution of ToM.

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