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1.
Ann Neurol ; 96(2): 365-377, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38845484

RESUMO

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. Complicated mild, moderate, and severe TBI (cmsTBI) is associated with a higher predicted age difference (PAD), but the progression of PAD over time remains unclear. We sought to examine whether PAD increases as a function of time since injury (TSI) and if injury severity and sex interacted to influence this progression. METHODS: Through the ENIGMA Adult Moderate and Severe (AMS)-TBI working group, we examine the largest TBI sample to date (n = 343), along with controls, for a total sample size of n = 540, to replicate and extend prior findings in the study of TBI brain age. Cross-sectional T1w-MRI data were aggregated across 7 cohorts, and brain age was established using a similar brain age algorithm to prior work in TBI. RESULTS: Findings show that PAD widens with longer TSI, and there was evidence for differences between sexes in PAD, with men showing more advanced brain age. We did not find strong evidence supporting a link between PAD and cognitive performance. INTERPRETATION: This work provides evidence that changes in brain structure after cmsTBI are dynamic, with an initial period of change, followed by relative stability in brain morphometry, eventually leading to further changes in the decades after a single cmsTBI. ANN NEUROL 2024;96:365-377.


Assuntos
Lesões Encefálicas Traumáticas , Imageamento por Ressonância Magnética , Humanos , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/complicações , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudos de Coortes , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Idoso , Envelhecimento/patologia , Senilidade Prematura/diagnóstico por imagem , Senilidade Prematura/patologia
2.
J Int Neuropsychol Soc ; 29(2): 159-171, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35225201

RESUMO

OBJECTIVE: Personal beliefs about memory ability, which comprise memory self-efficacy (MSE), can influence memory performance in healthy older adults. Self-efficacy theory also predicts that MSE biases self-perceptions of functioning more globally, potentially impacting daily activity beyond cognitive performance. People with traumatic brain injury (PwTBI) frequently report debilitating memory problems long after acute recovery, but little is known about how MSE affects health outcomes in this population. We examined demographic and clinical correlates of MSE, as well as its relationship to memory test performance and health-related quality of life (QOL), in older adults with chronic moderate-to-severe TBI (msTBI). METHOD: One hundred fourteen adults, aged 50+ and at least 1 year post-msTBI, underwent neuropsychological testing to assess their memory functioning. Participants also self-reported levels of psychological distress, MSE (Cognitive Confidence subscale of the Metacognitions Questionnaire), and health-related QOL (Quality of Life after Brain Injury questionnaire). RESULTS: Demographic and injury-related predictors showed weak correlations with MSE. Although the relationship between MSE and general psychological distress was robust, only the former significantly predicted memory performance. Bivariate analyses revealed significant relationships between MSE and five out of the six QOL domains assessed. Multivariate linear regression revealed a significant impact of MSE on overall QOL independent of demographic and clinical variables. CONCLUSIONS: Our findings support a unique role for MSE in both the objective cognitive performance and subjective health of PwTBI. Increased focus on self-perceptions of ability and their impact on measured outcomes is an important step towards personalized rehabilitation for adults with chronic msTBI.


Assuntos
Lesões Encefálicas Traumáticas , Qualidade de Vida , Humanos , Idoso , Envelhecimento , Cognição , Lesões Encefálicas Traumáticas/psicologia , Percepção
3.
J Head Trauma Rehabil ; 38(2): 191-200, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36731038

RESUMO

OBJECTIVE: To evaluate major and everyday experiences of discrimination (MED and EED, respectively) in relation to behavioral health outcomes in people with traumatic brain injury (PwTBI). SETTING: Outpatient research laboratory. PARTICIPANTS: Adults, 50 years or older, with a chronic (1+ year) history of moderate or severe TBI ( N = 118). DESIGN: Cross-sectional observational study. MAIN MEASURES: MED and EED (primary measures of interest) and behavioral health outcomes: global cognition, psychological symptoms, neurobehavioral symptoms, societal participation, and health-related quality of life (HRQoL). In participants with available geodata ( N = 28), neighborhood socioeconomic deprivation (ND) was examined as a potential contributor to MED, EED, and measured outcomes. RESULTS: EED and MED were significantly associated with psychological symptoms, neurobehavioral symptoms, and HRQoL after correction for multiple comparisons. Counter to expectations, EED were related to higher societal participation. MED and EED were unrelated to cognition. When MED and EED were entered together in hierarchical regressions, only EED made significant contributions beyond demographic and injury-related covariates to each outcome. Sensitivity analyses revealed that most of these relationships were not solely accounted for by disability-related discrimination. ND showed negligible associations with discrimination but moderate effect sizes for cognition and participation. Race was not significantly related to discrimination and was not a significant predictor in regression models but was strongly associated with ND. CONCLUSION: The current data provide preliminary support for perceived discrimination as an important factor in neurobehavioral and psychosocial health, but not cognitive performance, after TBI. These relationships appear to be driven by daily experiences of discriminatory treatment versus single major instances of injustice. Measured outcomes may also reflect socioeconomic challenges and structural discrimination faced by diverse PwTBI, although more work in this area is urgently needed. Multiple sources of marginalization and disenfranchisement and their functional effects should be considered in TBI rehabilitation and outcome monitoring.


Assuntos
Lesões Encefálicas Traumáticas , Discriminação Percebida , Qualidade de Vida , Humanos , Envelhecimento , Lesões Encefálicas Traumáticas/psicologia , Estudos Transversais , Avaliação de Resultados em Cuidados de Saúde , Pessoa de Meia-Idade
4.
J Head Trauma Rehabil ; 38(4): E254-E266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36602276

RESUMO

OBJECTIVE: Mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) commonly occur among military Service Members and Veterans and have heterogenous, but also overlapping symptom presentations, which often complicate the diagnoses of underlying impairments and development of effective treatment plans. Thus, we sought to examine whether the combination of whole brain gray matter (GM) and white matter (WM) structural measures with neuropsychological performance can aid in the classification of military personnel with mTBI and PTSD. METHODS: Active-Duty US Service Members ( n = 156; 87.8% male) with a history of mTBI, PTSD, combined mTBI+PTSD, or orthopedic injury completed a neuropsychological battery and T1- and diffusion-weighted structural neuroimaging. Cortical, subcortical, ventricular, and WM volumes and whole brain fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) were calculated. Latent profile analyses were performed to determine how the GM and WM indicators, together with neuropsychological indicators, classified individuals. RESULTS: For both GM and WM, respectively, a 4-profile model was the best fit. The GM model identified greater ventricular volumes in Service Members with cognitive symptoms, including those with a diagnosis of mTBI, either alone or with PTSD. The WM model identified reduced FA and elevated RD in those with psychological symptoms, including those with PTSD or mTBI and comorbid PTSD. However, contrary to expectation, a global neural signature unique to those with comorbid mTBI and PTSD was not identified. CONCLUSIONS: The findings demonstrate that neuropsychological performance alone is more robust in differentiating Active-Duty Service Members with mTBI and PTSD, whereas global neuroimaging measures do not reliably differentiate between these groups.


Assuntos
Concussão Encefálica , Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Masculino , Humanos , Feminino , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Encéfalo/diagnóstico por imagem , Veteranos/psicologia , Neuroimagem
5.
Hum Brain Mapp ; 43(1): 149-166, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32476212

RESUMO

Traumatic brain injury (TBI) is a major cause of disability worldwide, but the heterogeneous nature of TBI with respect to injury severity and health comorbidities make patient outcome difficult to predict. Injury severity accounts for only some of this variance, and a wide range of preinjury, injury-related, and postinjury factors may influence outcome, such as sex, socioeconomic status, injury mechanism, and social support. Neuroimaging research in this area has generally been limited by insufficient sample sizes. Additionally, development of reliable biomarkers of mild TBI or repeated subconcussive impacts has been slow, likely due, in part, to subtle effects of injury and the aforementioned variability. The ENIGMA Consortium has established a framework for global collaboration that has resulted in the largest-ever neuroimaging studies of multiple psychiatric and neurological disorders. Here we describe the organization, recent progress, and future goals of the Brain Injury working group.


Assuntos
Lesões Encefálicas Traumáticas , Neuroimagem , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/fisiopatologia , Humanos , Estudos Multicêntricos como Assunto
6.
J Head Trauma Rehabil ; 37(3): E196-E205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34145164

RESUMO

OBJECTIVE: To examine the influence of 2 temporal factors-age and injury chronicity-on the relationship between cognitive reserve (CR) and cognitive functioning in older adults with chronic traumatic brain injury (TBI). SETTING: Outpatient research laboratory. PARTICIPANTS: Adults, 50 years or older, with a 1- to 45-year history of moderate or severe TBI (N = 108). DESIGN: Cross-sectional observational study. MAIN MEASURES: CR was estimated using demographically corrected performance on a word-reading test (an approximation of premorbid IQ). Injury chronicity was operationalized as number of years since the date of injury. Composite cognitive scores were computed from performances on neuropsychological tests of processing speed, executive functioning, and memory. RESULTS: CR was positively and significantly related to all cognitive performances independent of age, injury chronicity, and injury severity. Greater injury chronicity significantly attenuated the effect of CR on processing speed such that individuals more distal from their injury date evidenced a weaker positive relationship between CR and performance. CONCLUSION: Temporal factors may modify associations between CR and cognition. Findings suggest that the protective effects of CR are temporally delimited, potentially contending with declines in brain reserve. The prognostic value of traditional outcome determinants should be considered in the context of injury chronicity.


Assuntos
Lesões Encefálicas Traumáticas , Reserva Cognitiva , Idoso , Envelhecimento , Lesões Encefálicas Traumáticas/psicologia , Cognição , Estudos Transversais , Humanos , Testes Neuropsicológicos
7.
J Head Trauma Rehabil ; 37(6): E438-E448, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35452025

RESUMO

OBJECTIVE: To determine whether cognitive and psychological symptom profiles differentiate clinical diagnostic classifications (eg, history of mild traumatic brain injury [mTBI] and posttraumatic stress disorder [PTSD]) in military personnel. METHODS: US Active-Duty Service Members ( N = 209, 89% male) with a history of mTBI ( n = 56), current PTSD ( n = 23), combined mTBI + PTSD ( n = 70), or orthopedic injury controls ( n = 60) completed a neuropsychological battery assessing cognitive and psychological functioning. Latent profile analysis was performed to determine how neuropsychological outcomes of individuals clustered together. Diagnostic classifications (ie, mTBI, PTSD, mTBI + PTSD, and orthopedic injury controls) within each symptom profile were examined. RESULTS: A 5-profile model had the best fit. The profiles differentiated subgroups with high (34.0%) or normal (21.5%) cognitive and psychological functioning, cognitive symptoms (19.1%), psychological symptoms (15.3%), and combined cognitive and psychological symptoms (10.0%). The symptom profiles differentiated participants as would generally be expected. Participants with PTSD were mainly represented in the psychological symptom subgroup, while orthopedic injury controls were mainly represented in the high-functioning subgroup. Further, approximately 79% of participants with comorbid mTBI and PTSD were represented in a symptomatic group (∼24% = cognitive symptoms, ∼29% = psychological symptoms, and 26% = combined cognitive/psychological symptoms). Our results also showed that approximately 70% of military personnel with a history of mTBI were represented in the high- and normal-functioning groups. CONCLUSIONS: These results demonstrate both overlapping and heterogeneous symptom and performance profiles in military personnel with a history of mTBI, PTSD, and/or mTBI + PTSD. The overlapping profiles may underscore why these diagnoses are often difficult to diagnose and treat, but suggest that advanced statistical models may aid in identifying profiles representing symptom and cognitive performance impairments within patient groups and enable identification of more effective treatment targets.


Assuntos
Concussão Encefálica , Disfunção Cognitiva , Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Masculino , Humanos , Feminino , Concussão Encefálica/epidemiologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Militares/psicologia , Comorbidade , Disfunção Cognitiva/diagnóstico , Veteranos/psicologia
8.
Brain Inj ; 36(9): 1109-1117, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35996331

RESUMO

OBJECTIVE: We aimed to examine acute trauma outcomes, specifically among those with neurotrauma (NT), in patients with preexisting cerebrovascular accident (CVA). METHODS: We identified patients treated for neurotrauma or orthopedic trauma at hospitals in Pennsylvania with and without an identified history of stroke with residual deficits, aged 50-99 across four groups of N = 11,648 each. We assessed mortality, craniotomy, and total hospital, ICU, step-down, and ventilator days, functional status at discharge (FSD), and discharge destination. RESULTS: Stroke history did not influence mortality but was predictive of patients undergoing craniotomy (OR = 1.25, p = 0.008). There was a moderate group effect on total ICU days, with the CVA+NT group in the ICU the longest (η2 = 0.10, p < 0.001). Patients with stroke history were less likely to be discharged to home (OR = 0.65, p < 0.001) and had poorer FSD scores across the various domains assessed. CONCLUSIONS: Trauma patients with preexisting CVA were found to have poorer outcomes on a number of different metrics when compared to those without stroke history. While it is possible that functional differences pre-injury influenced FSD and discharge destination, given these results, clinicians should assess for possible comorbidities that may influence treatment.


Assuntos
Acidente Vascular Cerebral , Ferimentos e Lesões , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Hospitalização , Humanos , Pessoa de Meia-Idade , Alta do Paciente , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/terapia
9.
Brain Inj ; 35(10): 1192-1200, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34460346

RESUMO

Primary ObjectiveEstablished literature demonstrates that homeless individuals experience both greater disease burden and risk of experiencing traumatic brain injury (TBI) than the general population. Similarly, shared risk factors for both homelessness and/or TBI may exacerbate the risk of repetitive neurotrauma within homeless populations.Research DesignWe leveraged a state-wide trauma registry, the Pennsylvania Trauma Outcome Study (PTOS), to characterize 609 patients discharged to homeless (58% TBI, 42% orthopedic injury (OI)) in comparison to 609 randomly sampled adult patients discharged to home.Methods and ProceduresWe implemented Chi-square tests to examine preexisting health conditions (PECs), hospital course, and injury mechanisms for both patient groups.Main Outcomes and ResultsHomelessness affects a greater proportion of nonwhite patients, and homeless patients present for care with increased frequencies of psychiatric and substance use PECs, and alcohol-positive TBI. Furthermore, assault impacts a larger proportion of homeless patients, and the window for overnight assault risk resulting in TBI is extended for these patients compared to patients discharged to home.ConclusionGiven the shifting conceptualization of TBI as a chronic condition, identifying homeless patients on admission to trauma centers, rather than retrospectively at discharge, can enhance understanding of the challenges facing the homeless as they age with both a complex neurotrauma history and multimorbidity.


Assuntos
Lesões Encefálicas Traumáticas , Pessoas Mal Alojadas , Adulto , Lesões Encefálicas Traumáticas/epidemiologia , Hospitais , Humanos , Estudos Retrospectivos , Centros de Traumatologia
10.
Brain Inj ; 34(6): 799-808, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32228303

RESUMO

PRIMARY OBJECTIVE: This study has three goals: to determine whether there is a higher rate of traumatic brain injury (TBI) for people of color (POC), whether TBI studies report racial/ethnic demographics, and whether there is a discrepancy in discharge destinations between Whites and POC. We examined whether 1) a higher percentage of POC would sustain head injuries than expected, 2) the majority of TBI studies examined (>50%) would not include racial/ethnic demographics, and 3) Whites would be discharged to further treatment over POC. RESEARCH DESIGN: Retrospective study and literature review. METHODS AND PROCEDURES: Data from the Pennsylvania Trauma System Foundation was used to determine the number of POC with TBI using X2 analysis, as well as where patients with TBI were being discharged using a configural frequency analysis. PubMed was used for the literature search to examine the frequency of reporting race/ethnicity in TBI literature. MAIN OUTCOMES AND RESULTS: Results demonstrated that Blacks sustain more TBIs than would be expected (p < .05), the majority of scientific studies (78%) do not report racial/ethnic demographic information, and Whites are discharged to further care more often than POC. CONCLUSIONS: These findings highlight differences in incidence and treatment of TBI between White individuals and POC, raising important considerations for providers and researchers.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Etnicidade , Lesões Encefálicas Traumáticas/epidemiologia , Humanos , Incidência , Pennsylvania/epidemiologia , Estudos Retrospectivos
11.
Depress Anxiety ; 33(11): 995-1004, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27093074

RESUMO

BACKGROUND: Extreme shyness in childhood arising from behavioral inhibition (BI) is among the strongest risk factors for developing social anxiety. Although no imaging studies of intrinsic brain networks in children with BI have been reported, adults with a history of BI exhibit altered functioning of frontolimbic circuits and enhanced processing of salient, personally relevant information. BI in childhood may be marked by increased coupling of salience (insula) and default (ventromedial prefrontal cortex [vmPFC]) network hubs. METHODS: We tested this potential relation in 42 children ages 9-12, oversampled for high BI. Participants provided resting-state functional magnetic resonance imaging. A novel topographical pattern analysis of salience network intrinsic functional connectivity was conducted, and the impact of salience-default coupling on the relation between BI and social anxiety symptoms was assessed via moderation analysis. RESULTS: Children with high BI exhibit altered salience network topography, marked by reduced insula connectivity to dorsal anterior cingulate and increased insula connectivity to vmPFC. Whole-brain analyses revealed increased connectivity of salience, executive, and sensory networks with default network hubs in children higher in BI. Finally, the relation between insula-ventromedial prefrontal connectivity and social anxiety symptoms was strongest among the children highest in BI. CONCLUSIONS: BI is associated with an increase in connectivity to default network hubs that may bias processing toward personally relevant information during development. These altered patterns of connectivity point to potential biomarkers of the neural profile of risk for anxiety in childhood.

12.
Neuroimage Clin ; 42: 103585, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38531165

RESUMO

Resting state functional magnetic resonance imaging (rsfMRI) provides researchers and clinicians with a powerful tool to examine functional connectivity across large-scale brain networks, with ever-increasing applications to the study of neurological disorders, such as traumatic brain injury (TBI). While rsfMRI holds unparalleled promise in systems neurosciences, its acquisition and analytical methodology across research groups is variable, resulting in a literature that is challenging to integrate and interpret. The focus of this narrative review is to address the primary methodological issues including investigator decision points in the application of rsfMRI to study the consequences of TBI. As part of the ENIGMA Brain Injury working group, we have collaborated to identify a minimum set of recommendations that are designed to produce results that are reliable, harmonizable, and reproducible for the TBI imaging research community. Part one of this review provides the results of a literature search of current rsfMRI studies of TBI, highlighting key design considerations and data processing pipelines. Part two outlines seven data acquisition, processing, and analysis recommendations with the goal of maximizing study reliability and between-site comparability, while preserving investigator autonomy. Part three summarizes new directions and opportunities for future rsfMRI studies in TBI patients. The goal is to galvanize the TBI community to gain consensus for a set of rigorous and reproducible methods, and to increase analytical transparency and data sharing to address the reproducibility crisis in the field.


Assuntos
Lesões Encefálicas Traumáticas , Imageamento por Ressonância Magnética , Humanos , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Reprodutibilidade dos Testes , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Descanso/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/normas , Mapeamento Encefálico/métodos , Mapeamento Encefálico/normas
13.
J Int Neuropsychol Soc ; 19(7): 751-62, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23656706

RESUMO

Individuals with mild traumatic brain injury (TBI) often have deficits in processing speed and working memory (WM) and there is a growing literature using functional imaging studies to document these deficits. However, divergent results from these studies revealed both hypoactivation and hyperactivation of neural resources after injury. We hypothesized that at least part of this variance can be explained by distinct demands between WM tasks. Notably, in this literature some WM tasks use discrete periods of encoding, maintenance, and retrieval, whereas others place continuous demands on WM. The purpose of this meta-analysis is to examine the differences in neural recruitment after mTBI to determine if divergent findings can be explained as a function of task demand and cognitive load. A comprehensive literature review revealed 14 studies using functional magnetic resonance imaging to examine brain activity of individuals with mTBI during working memory tasks. Three of the fourteen studies included reported hypoactivity, five reported hyperactivity, and the remaining six reported both hypoactivity and hyperactivity. Studies were grouped according to task type and submitted to GingerALE maximum likelihood meta-analyses to determine the most consistent brain activation patterns. The primary findings from this meta-analysis suggest that the discrepancy in activation patterns is at least partially attributable to the classification of WM task, with hyperactivation being observed in continuous tasks and hypoactivation being observed during discrete tasks. We anticipate that differential task load expressed in continuous and discrete WM tasks contributes to these differences. Implications for the interpretation of fMRI signals in clinical samples are discussed.


Assuntos
Lesões Encefálicas/fisiopatologia , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Memória de Curto Prazo/fisiologia , Humanos , Memória de Curto Prazo/classificação
14.
Brain Commun ; 5(1): fcac322, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36601624

RESUMO

The replication crisis poses important challenges to modern science. Central to this challenge is re-establishing ground truths or the most fundamental theories that serve as the bedrock to a scientific community. However, the goal to identify hypotheses with the greatest support is non-trivial given the unprecedented rate of scientific publishing. In this era of high-volume science, the goal of this study is to sample from one research community within clinical neuroscience (traumatic brain injury) and track major trends that have shaped this literature over the past 50 years. To do so, we first conduct a decade-wise (1980-2019) network analysis to examine the scientific communities that shape this literature. To establish the robustness of our findings, we utilized searches from separate search engines (Web of Science; Semantic Scholar). As a second goal, we sought to determine the most highly cited hypotheses influencing the literature in each decade. In a third goal, we then searched for any papers referring to 'replication' or efforts to reproduce findings within our >50 000 paper dataset. From this search, 550 papers were analysed to determine the frequency and nature of formal replication studies over time. Finally, to maximize transparency, we provide a detailed procedure for the creation and analysis of our dataset, including a discussion of each of our major decision points, to facilitate similar efforts in other areas of neuroscience. We found that the unparalleled rate of scientific publishing within the brain injury literature combined with the scarcity of clear hypotheses in individual publications is a challenge to both evaluating accepted findings and determining paths forward to accelerate science. Additionally, while the conversation about reproducibility has increased over the past decade, the rate of published replication studies continues to be a negligible proportion of the research. Meta-science and computational methods offer the critical opportunity to assess the state of the science and illuminate pathways forward, but ultimately there is structural change needed in the brain injury literature and perhaps others.

15.
Neuropsychology ; 37(4): 398-408, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35797175

RESUMO

OBJECTIVE: The variety of instruments used to assess posttraumatic stress disorder (PTSD) allows for flexibility, but also creates challenges for data synthesis. The objective of this work was to use a multisite mega analysis to derive quantitative recommendations for equating scores across measures of PTSD severity. METHOD: Empirical Bayes harmonization and linear models were used to describe and mitigate site and covariate effects. Quadratic models for converting scores across PTSD assessments were constructed using bootstrapping and tested on hold out data. RESULTS: We aggregated 17 data sources and compiled an n = 5,634 sample of individuals who were assessed for PTSD symptoms. We confirmed our hypothesis that harmonization and covariate adjustments would significantly improve inference of scores across instruments. Harmonization significantly reduced cross-dataset variance (28%, p < .001), and models for converting scores across instruments were well fit (median R² = 0.985) with an average root mean squared error of 1.46 on sum scores. CONCLUSIONS: These methods allow PTSD symptom severity to be placed on multiple scales and offers interesting empirical perspectives on the role of harmonization in the behavioral sciences. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Transtornos de Estresse Pós-Traumáticos , Veteranos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Teorema de Bayes , Índice de Gravidade de Doença
16.
Hum Brain Mapp ; 33(4): 979-93, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21591026

RESUMO

Previous studies of the BOLD response in the injured brain have revealed neural recruitment relative to controls during working memory tasks in several brain regions, most consistently the right prefrontal cortex and anterior cingulate cortices. We previously proposed that the recruitment observed in this literature represents auxiliary support resources, and that recruitment of PFC is not abnormal or injury specific and should reduce as novelty and challenge decrease. The current study directly tests this hypothesis in the context of practice of a working memory task. It was hypothesized that individuals with brain injury would demonstrate recruitment of previously indicated regions, behavioral improvement following task practice, and a reduction in the BOLD signal in recruited regions after practice. Individuals with traumatic brain injury and healthy controls performed the n-back during fMRI acquisition, practiced each task out of the scanner, and returned to the scanner for additional fMRI n-back acquisition. Statistical parametric maps demonstrated a number of regions of recruitment in the 1-back in individuals with brain injury and a number of corresponding regions of reduced activation in individuals with brain injury following practice in both the 1-back and 2-back. Regions of interest demonstrated reduced activation following practice, including the anterior cingulate and right prefrontal cortices. Individuals with brain injury demonstrated modest behavioral improvements following practice. These findings suggest that neural recruitment in brain injury does not represent reorganization but a natural extension of latent mechanisms that engage transiently and are contingent upon cerebral challenge.


Assuntos
Lesões Encefálicas/fisiopatologia , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Plasticidade Neuronal/fisiologia , Adolescente , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto Jovem
17.
J Int Neuropsychol Soc ; 18(2): 379-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22317853

RESUMO

The ability to appraise one's own ability has been found to have an important role in the recovery and quality of life of clinical populations. Examinee and task variables have been found to influence metacognition in healthy students; however the effect of these variables on the metacognitive accuracy of adults with neurological insult, such as traumatic brain injury (TBI), remains unknown. Twenty-two adults with moderate and severe TBI and a matched sample of healthy adults participated in this study examining the influence of item sequencing on metacognitive functioning. Retrospective confidence judgments were collected while participants completed a modified version of the Matrix Reasoning subtest. Significant influence of item sequence order was found, revealing better metacognitive abilities and performance when participants completed tasks where item difficulty progressed in order from easy to difficult. We interpret these findings to suggest that the sequencing of item difficulty offers "anchors" for gauging and adjusting to task demands.


Assuntos
Lesões Encefálicas/complicações , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Adolescente , Adulto , Análise de Variância , Lesões Encefálicas/classificação , Estudos de Casos e Controles , Feminino , Humanos , Testes de Inteligência , Julgamento , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Retrospectivos , Índices de Gravidade do Trauma , Adulto Jovem
18.
Brain ; 134(Pt 5): 1555-70, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21571783

RESUMO

There is mounting literature that examines brain activation during tasks of working memory in individuals with neurological disorders such as traumatic brain injury. These studies represent a foundation for understanding the functional brain changes that occur after moderate and severe traumatic brain injury, but the focus on topographical brain-'activation' differences ignores potential alterations in how nodes communicate within a distributed neural network. The present study makes use of the most recently developed connectivity modelling (extended-unified structural equation model) to examine performance during a well-established working-memory task (the n-back) in individuals sustaining moderate and severe traumatic brain injury. The goal is to use the findings observed in topographical activation analysis as the basis for second-level effective connectivity modelling. Findings reveal important between-group differences in within-hemisphere connectivity during task acquisition, with the control sample demonstrating rapid within-left hemisphere connectivity increases and the traumatic brain injury sample demonstrating consistently elevated within-right hemisphere connectivity. These findings also point to important maturational effects from 'early' to 'late' during task performance, including diminished right prefrontal cortex involvement and an anterior to posterior shift in connectivity with increased task exposure. We anticipate that this approach to functional imaging data analysis represents an important future direction for understanding how neural plasticity is expressed in brain disorders.


Assuntos
Lesões Encefálicas/complicações , Córtex Cerebral/patologia , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Memória de Curto Prazo/fisiologia , Rede Nervosa/patologia , Adulto , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Rede Nervosa/irrigação sanguínea , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Fatores de Tempo
19.
Elife ; 112022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35939392

RESUMO

The number of scientific papers published every year continues to increase, but scientific knowledge is not progressing at the same rate. Here we argue that a greater emphasis on falsification - the direct testing of strong hypotheses - would lead to faster progress by allowing well-specified hypotheses to be eliminated. We describe an example from neuroscience where there has been little work to directly test two prominent but incompatible hypotheses related to traumatic brain injury. Based on this example, we discuss how building strong hypotheses and then setting out to falsify them can bring greater precision to the clinical neurosciences, and argue that this approach could be beneficial to all areas of science.


Assuntos
Neurociências , Relatório de Pesquisa
20.
Netw Neurosci ; 6(1): 29-48, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35350584

RESUMO

In this critical review, we examine the application of predictive models, for example, classifiers, trained using machine learning (ML) to assist in interpretation of functional neuroimaging data. Our primary goal is to summarize how ML is being applied and critically assess common practices. Our review covers 250 studies published using ML and resting-state functional MRI (fMRI) to infer various dimensions of the human functional connectome. Results for holdout ("lockbox") performance was, on average, ∼13% less accurate than performance measured through cross-validation alone, highlighting the importance of lockbox data, which was included in only 16% of the studies. There was also a concerning lack of transparency across the key steps in training and evaluating predictive models. The summary of this literature underscores the importance of the use of a lockbox and highlights several methodological pitfalls that can be addressed by the imaging community. We argue that, ideally, studies are motivated both by the reproducibility and generalizability of findings as well as the potential clinical significance of the insights. We offer recommendations for principled integration of machine learning into the clinical neurosciences with the goal of advancing imaging biomarkers of brain disorders, understanding causative determinants for health risks, and parsing heterogeneous patient outcomes.

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