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Chiang HS, Motes M, Afkhami-Rohani B, Adhikari A, LoBue C, Kraut M, Cullum CM, Hart J. Verbal retrieval deficits due to traumatic brain injury are associated with changes in event related potentials during a Go-NoGo task. Clin Neurophysiol 2024; 163:1-13. [PMID: 38663098 DOI: 10.1016/j.clinph.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/04/2024] [Accepted: 04/07/2024] [Indexed: 06/15/2024]
Abstract
OBJECTIVE Verbal retrieval (VR) deficits often occur after traumatic brain injury (TBI), but the mechanisms remain unclear. We examined how event-related potentials (ERPs) during a Go-NoGo task were associated with VR deficits. METHODS Sixty veterans with a history of TBI underwent a neuropsychological battery and a Go-NoGo task with concurrent EEG recording. We compared task performance and ERP measures (N2, P3) between those with and those without persistent injury-related VR deficits. We then used generalized linear modeling to examine the relationship between ERP measures and scores on measures of executive function and processing speed. RESULTS Go-NoGo task performance was comparable between the groups. Those with VR deficits had larger N2 amplitude in NoGo than in Go conditions. In participants with VR deficits, larger NoGo N2/P3 amplitude predicted faster processing speed. Furthermore, larger P3 amplitude and shorter P3 latency of the difference wave (NoGo - Go) predicted faster processing speed in those with VR deficits. CONCLUSIONS Despite no difference in Go-NoGo task performance, ERP amplitude and latency measures associated with cognitive control during Go-NoGo distinguished TBI individuals with VR deficits from those without. SIGNIFICANCE This study furthers our understanding of VR deficits in TBI and implicates potential application of ERP measures in monitoring and treating such deficits.
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Affiliation(s)
- Hsueh-Sheng Chiang
- University of Texas Southwestern Medical Center, Department of Neurology, USA; The University of Texas at Dallas, School of Behavioral and Brain Sciences, USA.
| | - Michael Motes
- The University of Texas at Dallas, School of Behavioral and Brain Sciences, USA.
| | - Borna Afkhami-Rohani
- The University of Texas at Dallas, School of Behavioral and Brain Sciences, USA.
| | - Ashna Adhikari
- The University of Texas at Dallas, School of Behavioral and Brain Sciences, USA.
| | - Christian LoBue
- University of Texas Southwestern Medical Center, Department of Psychiatry, USA; University of Texas Southwestern Medical Center, Department of Neurological Surgery, USA.
| | - Michael Kraut
- The Johns Hopkins School of Medicine, Department of Radiology, USA.
| | - C Munro Cullum
- University of Texas Southwestern Medical Center, Department of Neurology, USA; University of Texas Southwestern Medical Center, Department of Psychiatry, USA; University of Texas Southwestern Medical Center, Department of Neurological Surgery, USA.
| | - John Hart
- University of Texas Southwestern Medical Center, Department of Neurology, USA; The University of Texas at Dallas, School of Behavioral and Brain Sciences, USA; University of Texas Southwestern Medical Center, Department of Psychiatry, USA.
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Chiang H, Mudar RA, Dugas CS, Motes MA, Kraut MA, Hart J. A modified neural circuit framework for semantic memory retrieval with implications for circuit modulation to treat verbal retrieval deficits. Brain Behav 2024; 14:e3490. [PMID: 38680077 PMCID: PMC11056716 DOI: 10.1002/brb3.3490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 01/23/2024] [Accepted: 04/03/2024] [Indexed: 05/01/2024] Open
Abstract
Word finding difficulty is a frequent complaint in older age and disease states, but treatment options are lacking for such verbal retrieval deficits. Better understanding of the neurophysiological and neuroanatomical basis of verbal retrieval function may inform effective interventions. In this article, we review the current evidence of a neural retrieval circuit central to verbal production, including words and semantic memory, that involves the pre-supplementary motor area (pre-SMA), striatum (particularly caudate nucleus), and thalamus. We aim to offer a modified neural circuit framework expanded upon a memory retrieval model proposed in 2013 by Hart et al., as evidence from electrophysiological, functional brain imaging, and noninvasive electrical brain stimulation studies have provided additional pieces of information that converge on a shared neural circuit for retrieval of memory and words. We propose that both the left inferior frontal gyrus and fronto-polar regions should be included in the expanded circuit. All these regions have their respective functional roles during verbal retrieval, such as selection and inhibition during search, initiation and termination of search, maintenance of co-activation across cortical regions, as well as final activation of the retrieved information. We will also highlight the structural connectivity from and to the pre-SMA (e.g., frontal aslant tract and fronto-striatal tract) that facilitates communication between the regions within this circuit. Finally, we will discuss how this circuit and its correlated activity may be affected by disease states and how this circuit may serve as a novel target engagement for neuromodulatory treatment of verbal retrieval deficits.
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Affiliation(s)
- Hsueh‐Sheng Chiang
- Department of NeurologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
- School of Behavioral and Brain SciencesThe University of Texas at DallasRichardsonTexasUSA
| | - Raksha A. Mudar
- Department of Speech and Hearing ScienceUniversity of Illinois Urbana‐ChampaignChampaignIllinoisUSA
| | - Christine S. Dugas
- School of Behavioral and Brain SciencesThe University of Texas at DallasRichardsonTexasUSA
| | - Michael A. Motes
- School of Behavioral and Brain SciencesThe University of Texas at DallasRichardsonTexasUSA
| | - Michael A. Kraut
- Department of Radiology and Radiological ScienceJohns Hopkins UniversityBaltimoreMarylandUSA
| | - John Hart
- Department of NeurologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
- School of Behavioral and Brain SciencesThe University of Texas at DallasRichardsonTexasUSA
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Schwertfeger JL, Beyer C, Hung P, Ung N, Madigan C, Cortes AR, Swaminathan B, Madhavan S. A map of evidence using transcranial direct current stimulation (tDCS) to improve cognition in adults with traumatic brain injury (TBI). FRONTIERS IN NEUROERGONOMICS 2023; 4:1170473. [PMID: 38234478 PMCID: PMC10790940 DOI: 10.3389/fnrgo.2023.1170473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/04/2023] [Indexed: 01/19/2024]
Abstract
Introduction Cognition impairments often occur after a traumatic brain injury and occur at higher rates in military members. Cognitive symptoms impair daily function, including balance and life quality, years after the TBI. Current treatments to regain cognitive function after TBI, including medications and cognitive rehabilitation, have shown limited effectiveness. Transcranial direct current stimulation (tDCS) is a low-cost, non-invasive brain stimulation intervention that improves cognitive function in healthy adults and people with neuropsychologic diagnoses beyond current interventions. Despite the available evidence of the effectiveness of tDCS in improving cognition generally, only two small TBI trials have been conducted based on the most recent systematic review of tDCS effectiveness for cognition following neurological impairment. We found no tDCS studies that addressed TBI-related balance impairments. Methods A scoping review using a peer-reviewed search of eight databases was completed in July 2022. Two assessors completed a multi-step review and completed data extraction on included studies using a priori items recommended in tDCS and TBI research guidelines. Results A total of 399 results were reviewed for inclusion and 12 met the criteria and had data extracted from them by two assessors using Google Forms. Consensus on combined data results included a third assessor when needed. No studies using tDCS for cognition-related balance were found. Discussion Guidelines and technology measures increase the identification of brain differences that alter tDCS effects on cognition. People with mild-severe and acute-chronic TBI tolerated and benefited from tDCS. TBI-related cognition is understudied, and systematic research that incorporates recommended data elements is needed to advance tDCS interventions to improve cognition after TBI weeks to years after injury.
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Affiliation(s)
- Julie Lynn Schwertfeger
- Captain James A. Lovell Federal Health Care Center, United States Department of Veteran Affairs, North Chicago, IL, United States
- Clinical Medicine, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Charlotte Beyer
- Department of Foundational Sciences and Humanities, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Paul Hung
- Captain James A. Lovell Federal Health Care Center, United States Department of Veteran Affairs, North Chicago, IL, United States
- Psychiatry Residency Program, Clinical Medicine, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Nathaniel Ung
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Caroline Madigan
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Alvi Renzyl Cortes
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Bharathi Swaminathan
- Physical Medicine and Rehabilitation, Captain James A. Lovell Federal health Care Center, North Chicago, IL, United States
- PM&R Residency Program, Clinical Medicine, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Sangeetha Madhavan
- Rehabilitation Sciences Program, and Physical Therapy Program, University of Illinois Chicago, Chicago, IL, United States
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Guo Z, Qiu R, Qiu H, Lu H, Zhu X. Long-term effects of repeated multitarget high-definition transcranial direct current stimulation combined with cognitive training on response inhibition gains. Front Neurosci 2023; 17:1107116. [PMID: 36968503 PMCID: PMC10033537 DOI: 10.3389/fnins.2023.1107116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/24/2023] [Indexed: 03/11/2023] Open
Abstract
BackgroundFew studies have investigated the effects of repeated sessions of transcranial direct current stimulation (tDCS) combined with concurrent cognitive training on improving response inhibition, and the findings have been heterogeneous in the limited research. This study investigated the long-lasting and transfer effects of 10 consecutive sessions of multitarget anodal HD-tDCS combined with concurrent cognitive training on improving response inhibition compared with multitarget stimulation or training alone.MethodsNinety-four healthy university students aged 18–25 were randomly assigned to undergo different interventions, including real stimulation combined with stop-signal task (SST) training, real stimulation, sham stimulation combined with SST training, and sham stimulation. Each intervention lasted 20 min daily for 10 consecutive days, and the stimulation protocol targeted right inferior frontal gyrus (rIFG) and pre-supplementary motor area (pre-SMA) simultaneously with a total current intensity of 2.5 mA. Performance on SST and possible transfer effects to Stroop task, attention network test, and N-back task were measured before and 1 day and 1 month after completing the intervention course.ResultsThe main findings showed that the combined protocol and the stimulation alone significantly reduced stop-signal reaction time (SSRT) in the post-intervention and follow-up tests compared to the pre-intervention test. However, training alone only decreased SSRT in the post-test. The sham control exhibited no changes. Subgroup analysis revealed that the combined protocol and the stimulation alone induced a decrease in the SSRT of the low-performance subgroup at the post-test and follow-up test compared with the pre-test. However, only the combined protocol, but not the stimulation alone, improved the SSRT of the high-performance subgroup. The transfer effects were absent.ConclusionThis study provides supportive evidence for the synergistic effect of the combined protocol, indicating its superiority over the single intervention method. In addition, the long-term after-effects can persist for up to at least 1 month. Our findings also provide insights into the clinical application and strategy for treating response inhibition deficits.
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Chiang HS, Motes M, Kraut M, Vanneste S, Hart J. High-definition transcranial direct current stimulation modulates theta response during a Go-NoGo task in traumatic brain injury. Clin Neurophysiol 2022; 143:36-47. [PMID: 36108520 PMCID: PMC10545365 DOI: 10.1016/j.clinph.2022.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 08/08/2022] [Accepted: 08/24/2022] [Indexed: 11/03/2022]
Abstract
OBJECTIVE High Definition transcranial Direct Current Stimulation (HD-tDCS) has been shown to improve cognitive performance in individuals with chronic traumatic brain injury (TBI), although electrophysiological mechanisms remain unclear. METHODS Veterans with TBI underwent active anodal (N = 15) vs sham (N = 10) HD-tDCS targeting the pre-supplementary motor area (pre-SMA). A Go-NoGo task was conducted simultaneously with electroencephalography (EEG) at baseline and after intervention completion. RESULTS We found increased theta event-related spectral perturbation (ERSP) and inter-trial phase coherence (ITPC) during Go in the frontal midline electrodes overlying the pre-SMA after active HD-tDCS intervention, but not after sham. We also found increased theta phase coherence during Go between the frontal midline and left posterior regions after active HD-tDCS. A late increase in alpha-theta ERSP was found in the left central region after active HD-tDCS. Notably, lower baseline theta ERSP/ITPC in the frontal midline region predicted more post-intervention improvement in Go performance only in the active group. CONCLUSIONS There are local and interregional oscillatory changes in response to HD-tDCS modulation in chronic TBI. SIGNIFICANCE These findings may guide future research in utilizing EEG time-frequency metrics not only to measure interventional effects, but also in selecting candidates who may optimally respond to treatment.
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Affiliation(s)
- Hsueh-Sheng Chiang
- Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX 75080, USA.
| | - Michael Motes
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX 75080, USA.
| | - Michael Kraut
- Department of Radiology, The Johns Hopkins University School of Medicine, 601 N Caroline St, Baltimore, MD 21205, USA.
| | - Sven Vanneste
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX 75080, USA; Trinity College Dublin, The University of Dublin, College Green, Dublin 2, Ireland.
| | - John Hart
- Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX 75080, USA.
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Chiang HS, Shakal S, Strain JF, Womack K, Kraut M, Vanneste S, Hart J. Reversal of unilateral hand movement dysfunction by high definition transcranial direct current stimulation in a patient with chronic traumatic brain injury. Brain Stimul 2022; 15:283-285. [PMID: 35066190 DOI: 10.1016/j.brs.2022.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 01/16/2022] [Indexed: 11/18/2022] Open
Affiliation(s)
- Hsueh-Sheng Chiang
- Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard Dallas, Texas, 75390, USA; The University of Texas Southwestern Medical Center, Dallas, TX, USA; The University of Texas at Dallas, Richardson, TX, USA.
| | - Scott Shakal
- The University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
| | - Jeremy F Strain
- Department of Neurology, Washington University in St. Louis, 660 S Euclid Ave, St. Louis, MO, 63108, USA.
| | - Kyle Womack
- Department of Neurology, Washington University in St. Louis, Campus Box 8111, 4488 Forest Park, Suite 200, St. Louis, MO, 63108, USA.
| | - Michael Kraut
- Department of Radiology, The Johns Hopkins University School of Medicine, 601 N Caroline St, Baltimore, MD, 21205, USA.
| | - Sven Vanneste
- Trinity College Dublin, The University of Dublin, College Green Dublin 2, Ireland.
| | - John Hart
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX, 75080, USA; Department of Neurology and Psychiatry, The University of Texas Southwestern Medical Center, USA.
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Krishnamurthy LC, Paredes Spir I, Rocha NO, Soher BJ, Auerbach EJ, Crosson BA, Krishnamurthy V. The association between language-based task-functional magnetic resonance imaging hemodynamics and baseline GABA+ and glutamate-glutamine measured in pre-supplementary motor area: A pilot study in an aging model. Front Psychiatry 2022; 13:904845. [PMID: 36046162 PMCID: PMC9421126 DOI: 10.3389/fpsyt.2022.904845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 07/28/2022] [Indexed: 11/13/2022] Open
Abstract
Aging is a natural phenomenon that elicits slow and progressive cerebrovascular and neurophysiological changes that eventually lead to cognitive decline. The objective of this pilot study is to examine the association of GABA+ and glutamate-glutamine (Glx) complex with language-based blood oxygen level dependent (BOLD) hemodynamics in an aging model. More specifically, using standard BOLD we will first attempt to validate whether previously reported findings for BOLD amplitude and resting neurochemical relationships hold in an aging model. Secondly, we will investigate how our recently established neurosensitized task-BOLD energetics relate to resting GABA+ and Glx, especially accounting for titration of task difficulty. To support the above endeavors, we optimize the baseline fitting for edited magnetic resonance spectroscopy (MRS) difference spectra to sensitize GABA+ and Glx concentrations to aging-related differences. We identify a spline-knot spacing of 0.6ppm to yield the optimal aging-related differences in GABA+ and Glx. The optimized MRS values were then graduated to relate to task-BOLD hemodynamics. Our results did not replicate previous findings that relate task-BOLD amplitude and resting GABA+ and Glx. However, we did identify neurochemistry relationships with the vascularly-driven dispersion component of the hemodynamic response function, specifically in older participants. In terms of neuro-sensitized BOLD energetics and the underlying role of GABA+ and Glx, our data suggests that the task demands are supported by both neurometabolites depending on the difficulty of the task stimuli. Another novelty is that we developed task-based functional parcellation of pre-SMA using both groups. In sum, we are the first to demonstrate that multimodal task-fMRI and MRS studies are beneficial to improve our understanding of the aging brain physiology, and to set the platform to better inform approaches for clinical care in aging-related neurovascular diseases. We also urge future studies to replicate our findings in a larger population incorporating a lifespan framework.
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Affiliation(s)
- Lisa C Krishnamurthy
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States.,Department of Physics & Astronomy, Georgia State University, Atlanta, GA, United States.,Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States
| | - Isabella Paredes Spir
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
| | - Natalie O Rocha
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States.,Department of Biology, Georgia State University, Atlanta, GA, United States
| | - Brian J Soher
- Center for Advanced MR Development, Department of Radiology, Duke University, Durham, NC, United States.,Brain Imaging and Analysis Center, Duke University, Durham, NC, United States
| | - Edward J Auerbach
- Department of Radiology, University of Minnesota, Minneapolis, MN, United States.,Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Bruce A Crosson
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States.,Department of Psychology, Georgia State University, Atlanta, GA, United States.,Department of Neurology, Emory University, Atlanta, GA, United States
| | - Venkatagiri Krishnamurthy
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States.,Department of Neurology, Emory University, Atlanta, GA, United States.,Division of Geriatrics and Gerontology, Department of Medicine, Emory University, Atlanta, GA, United States
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Chiang HS, Motes M, O'Hair R, Vanneste S, Kraut M, Hart J. Baseline delayed verbal recall predicts response to high definition transcranial direct current stimulation targeting the superior medial frontal cortex. Neurosci Lett 2021; 764:136204. [PMID: 34478816 DOI: 10.1016/j.neulet.2021.136204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/25/2021] [Accepted: 08/29/2021] [Indexed: 11/21/2022]
Abstract
Anodal high definition transcranial direct current stimulation (HD-tDCS) targeting the pre-supplementary motor area/dorsal anterior cingulate cortex (pre-SMA/dACC) has recently been shown to improve verbal retrieval deficits in veterans with chronic traumatic brain injury (TBI) (Motes et al., 2020), but predictors of treatment response are unclear. We hypothesized that baseline delayed verbal recall, a sensitive measure for post-TBI chronic cognitive decline, would predict therapeutic effects of HD-tDCS targeting the pre-SMA/dACC for verbal retrieval deficits. Standardized verbal retrieval measures were administered at baseline, immediately after and 8 weeks after treatment completion. We applied mixed generalized linear modeling as a post-hoc subgroup analysis to the verbal retrieval scores that showed significant improvement in Motes at el. (2020) to examine effects of active stimulation across the groups with baseline-intact delayed recall (N = 10) and baseline-impaired delayed recall (N = 8), compared to sham (N = 7). Individuals with impaired baseline delayed recall showed significant improvement (compared to baseline) in both category fluency and color-word inhibition/switch, while individuals with intact delayed recall showed significant improvement only in color-word inhibition/switch. Baseline delayed verbal recall may therefore be considered as a predictor for future electromodulation studies targeting frontal structures to treat TBI-related verbal deficits.
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Affiliation(s)
- Hsueh-Sheng Chiang
- Department of Neurology, The University of Texas Southwestern Medical Center, USA; School of Behavioral and Brain Sciences, The University of Texas at Dallas, USA.
| | - Michael Motes
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, USA
| | - Rachel O'Hair
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, USA
| | - Sven Vanneste
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, USA; Global Brain Health Institute, Trinity College Dublin, Ireland
| | - Michael Kraut
- Department of Radiology, The Johns Hopkins University School of Medicine, USA
| | - John Hart
- Department of Neurology, The University of Texas Southwestern Medical Center, USA; School of Behavioral and Brain Sciences, The University of Texas at Dallas, USA; Department of Psychiatry, The University of Texas Southwestern Medical Center, USA
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