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Enhancing Human Cognitive Capital by Harnessing the Brain’s Inherent Neuroplasticity
Abstract
This chapter addresses the capability to enhance human cognitive performance (i.e., cognitive capital) through training, with the down-range goal of improving functionality in contexts of great complexity, including military/political operations, corporate directions, and educational preparation. It highlights a multidimensional framework to measure gains in cognitive capital on brain, cognitive, psychological, life-functionality, and emotional-cognition factors. To illustrate the potential to harness neuroplasticity, the chapter summarizes evidence showing improved agility and focus from a specific cognitive training that targets strategic thinking (e.g., filter/focus, big picture thinking, innovation). This chapter also adds to the notion of increasing peak performance utilizing moderate stress levels to boost responses. Optimizing performance in continually changing and stressful environments relies on strengthening human cognitive capital in the healthy brain across the life span—similar to that achieved for physical fitness.
... Whereas specific mindfulness training was not a part of the SMART protocol, the training included strategies whereby participants were tasked with 'quieting the mind' with regular brain breaks, specifically taking 5 -five-minute breaks throughout the day. A brain break specifies that an individual move away from all tasks requiring mental effort to let the brain free up from effortful thinking to allow ideas to free float for 'aha' moments of innovative thinking (Chapman et al., 2019). Another key training strategy was for individuals to daily embrace as much change as possible to spark innovation and possibility thinking, since fluidity of ideas has been shown to be a key driver for enhanced brain performance (Chapman et al., , 2019. ...
... A brain break specifies that an individual move away from all tasks requiring mental effort to let the brain free up from effortful thinking to allow ideas to free float for 'aha' moments of innovative thinking (Chapman et al., 2019). Another key training strategy was for individuals to daily embrace as much change as possible to spark innovation and possibility thinking, since fluidity of ideas has been shown to be a key driver for enhanced brain performance (Chapman et al., , 2019. The brain is wired to adapt to change and gets quickly bored on rote thinking and actions. ...
Introduction
The workplace typically affords one of the longest periods for continued brain health growth. Brain health is defined by the World Health Organization (WHO) as the promotion of optimal brain development, cognitive health, and well-being across the life course, which we expanded to also include connectedness to people and purpose. This work was motivated by prior work showing individuals, outside of an aggregate setting, benefitted from training as measured by significant performance gains on a holistic BrainHealth Index and its factors (i.e., clarity, connectedness, emotional balance). The current research was conducted during the changing remote work practices emerging post-pandemic to test whether a capacity-building training would be associated with significant gains on measures of brain health and components of burnout. The study also tested the influence of utilization of training modules and days in office for individuals to inform workplace practices.
Methods
We investigated whether 193 individuals across a firm’s sites would improve on measures of brain health and burnout from micro-delivery of online tactical brain health strategies, combined with two individualized coaching sessions, and practical exercises related to work and personal life, over a six-month period. Brain health was measured using an evidenced-based measure (BrainHealth™ Index) with its components (clarity, connectedness, emotional balance) consistent with the WHO definition. Burnout was measured using the Maslach Burnout Inventory Human Services Survey. Days in office were determined by access to digital workplace applications from the firm’s network. Regression analyses were used to assess relationships between change in BrainHealth factors and change in components of the Maslach Burnout Inventory.
Results
Results at posttest indicated that 75% of the individuals showed gains on a composite BrainHealth Index and across all three composite factors contributing to brain health. Benefits were directly tied to training utilization such that those who completed the core modules showed the greatest gains. The current results also found an association between gains on both the connectedness and emotional balance brain health factors and reduced on burnout components of occupational exhaustion and depersonalization towards one’s workplace. We found that fewer days in the office were associated with greater gains in the clarity factor, but not for connectedness and emotional balance.
Discussion
These results support the value of a proactive, capacity-building training to benefit all employees to complement the more widespread limited offerings that address a smaller segment who need mental illness assistance programs. The future of work may be informed by corporate investment in focused efforts to boost collective brain capital through a human-centered, capacity-building approach. Efforts are underway to uncover the value of better brain health, i.e., Brainomics© - which includes economic, societal, and individual benefits.
... By bringing together our core measures of complex cognition, along with both novel and established measures of well-being, social connection, lifestyle, and purpose, the BrainHealth Index allows for both independent analysis of individual measures of brain health as well as a holistic view of how they interact with and impact overall function. Our strategy-based training protocol, known as SMART (Strategic Memory Advanced Reasoning Tactics), engages an executive function, top-down framework focusing on three core cognitive processes: Strategic Attention, Integrated Reasoning, and Innovation, described below [10]. SMART has shown e cacy in promoting gains in these cognitive areas and strengthening key brain networks that support planning, reasoning, decision-making, judgment, and emotional regulation [13]. ...
Background: Optimization of brain health is a focal point in medical science, yet data regarding measuring, preserving, and improving lifelong brain health are lacking. This void demands an objective, change-sensitive measure of brain health and proven strategies to strengthen brain performance. The BrainHealth Project addresses these key issues, drawing upon neuroplasticity evidence of persistent modifiability of brain function across the lifespan. This landmark study aims to definitively (i) evaluate and refine holistic change indices of brain health, (ii) evaluate the impact of evidenced-based cognitive strategies and lifestyle interventions on improving/maintaining brain health, and (iii) elucidate the mechanisms associated with brain health gains/losses.
Methods: This prospective, longitudinal, interventional, open-label, single-arm clinical trial aims to recruit 100,000 generally healthy adults over 10 years. Assessments, coaching, and training are conducted online through the secure BrainHealth Platform, allowing utilization tracking. The BrainHealth Index (BHI)—a multidimensional assessment—is offered at baseline and every six months. Participants have access to coaching every three months and continual access to self-paced trainings and resources.
The primary outcome is the further validation of a novel composite BHI score and its sub-scores: Clarity (cognitive health), Connectedness (social health), and Emotional Balance (well-being). The BHI includes measures sensitive to change, including gains from behavior change and integration of cognitive strategies into daily life. These contrast with traditional assessments focused on detecting cognitive decline or diagnosing pathological conditions.
The primary online training, SMART (Strategic Memory Advanced Reasoning Tactics), is a strategy-based program validated with 25+ years of research. SMART promotes improvements in neural health, cognition, well-being, connectedness, and real-life function, previously reported in randomized controlled trials (RCTs). Statistical approaches focus on individual prediction using nonlinear models trained with large samples and on assessing mechanisms influencing gains or losses on brain health metrics.
Discussion: This research extends RCT evidence to a longitudinal, epidemiologic approach, leveraging digital health and machine learning tools to deliver a generalizable measure of longitudinal brain health and to achieve precision brain health. By integrating advanced statistical methods and large-scale data, the BrainHealth Project should provide medicine and society with accurate and actionable ways to optimize brain health practices across the lifespan.
ClinicalTrials.gov Identifier: NCT04869111 (registered April 27, 2021)
Insidious declines in normal aging are well-established. Emerging evidence suggests that non-pharmacological interventions, specifically cognitive and physical training, may counter diminishing age-related cognitive and brain functions. This randomized trial compared effects of two training protocols: cognitive training (CT) vs. physical training (PT) on cognition and brain function in adults 56–75 years. Sedentary participants (N = 36) were randomized to either CT or PT group for 3 h/week over 12 weeks. They were assessed at baseline-, mid-, and post-training using neurocognitive, MRI, and physiological measures. The CT group improved on executive function whereas PT group's memory was enhanced. Uniquely deploying cerebral blood flow (CBF) and cerebral vascular reactivity (CVR) MRI, the CT cohort showed increased CBF within the prefrontal and middle/posterior cingulate cortex (PCC) without change to CVR compared to PT group. Improvements in complex abstraction were positively associated with increased resting CBF in dorsal anterior cingulate cortex (dACC). Exercisers with higher CBF in hippocampi bilaterally showed better immediate memory. The preliminary evidence indicates that increased cognitive and physical activity improves brain health in distinct ways. Reasoning training enhanced frontal networks shown to be integral to top-down cognitive control and brain resilience. Evidence of increased resting CBF without changes to CVR implicates increased neural health rather than improved vascular response. Exercise did not improve cerebrovascular response, although CBF increased in hippocampi of those with memory gains. Distinct benefits incentivize testing effectiveness of combined protocols to strengthen brain health.
Traumatic brain injury (TBI) is a chronic health condition. The prevalence of TBI, combined with limited advances in protocols to mitigate persistent TBI-related impairments in higher order cognition, present a significant challenge. In this randomised study (n = 60), we compared the benefits of Strategic Memory Advanced Reasoning Training (SMART, n = 31), a strategy-based programme shown to improve cognitive control, versus an active learning programme called Brain Health Workshop (BHW, n = 29) in individuals with TBI with persistent mild functional deficits. Outcomes were measured on cognitive, psychological health, functional, and imaging measures. Repeated measures analyses of immediate post-training and 3-month post-training demonstrated gains on the cognitive control domain of gist reasoning (ability to abstract big ideas/goals from complex information/tasks) in the SMART group as compared to BHW. Gains following the SMART programme were also evident on improved executive function, memory, and daily function as well as reduced symptoms associated with depression and stress. The SMART group showed an increase in bilateral precuneus cerebral blood flow (CBF). Improvements in gist reasoning in the SMART group were also associated with an increase in CBF in the left inferior frontal region, the left insula and the bilateral anterior cingulate cortex. These results add to prior findings that the SMART programme provides an efficient set of strategies that have the potential to improve cognitive control performance and associated executive functions and daily function, to enhance psychological health, and facilitate positive neural plasticity in adults with persistent mild impairment after TBI.
We investigated the impact of mindfulness training (MT) on attentional performance lapses associated with task-unrelated thought (i.e., mind wandering). Periods of persistent and intensive demands may compromise attention and increase off-task thinking. Here, we investigated if MT may mitigate these deleterious effects and promote cognitive resilience in military cohorts enduring a high-demand interval of predeployment training. To better understand which aspects of MT programs are most beneficial, three military cohorts were examined. Two of the three groups were provided MT. One group received an 8-hour, 8-week variant of Mindfulness-based Mind Fitness Training (MMFT) emphasizing engagement in training exercises (training-focused MT, n = 40), a second group received a didactic-focused variant emphasizing content regarding stress and resilience (didactic-focused MT, n = 40), and the third group served as a no-training control (NTC, n = 24). Sustained Attention to Response Task (SART) performance was indexed in all military groups and a no-training civilian group (CIV, n = 45) before (T1) and after (T2) the MT course period. Attentional performance (measured by A', a sensitivity index) was lower in NTC vs. CIV at T2, suggesting that performance suffers after enduring a high-demand predeployment interval relative to a similar time period of civilian life. Yet, there were significantly fewer performance lapses in the military cohorts receiving MT relative to NTC, with training-focused MT outperforming didactic-focused MT at T2. From T1 to T2, A' degraded in NTC and didactic-focused MT but remained stable in training-focused MT and CIV. In sum, while protracted periods of high-demand military training may increase attentional performance lapses, practice-focused MT programs akin to training-focused MT may bolster attentional performance more than didactic-focused programs. As such, training-focused MT programs should be further examined in cohorts experiencing protracted high-demand intervals.
Attention-Deficit/Hyperactivity Disorder (ADHD), a neuropsychiatric condition characterized by attention and impulsivity problems, is one of the most common behavioral disorders. The first line of treatment for ADHD is psychostimulant medication, but this has limited effectiveness, particularly in adults, and is often associated with adverse side-effects. Thus, it is imperative that new non-pharmaceutical approaches to treatment are developed. This study aims to evaluate the impact of a non-pharmacological Self-Alert Training (SAT) intervention on ADHD symptom prevalence, psychological and cognitive functioning, and on everyday functional impairment in adults with ADHD. Fifty-one adult participants with a current diagnosis of ADHD were randomized to either SAT or a Control Training (CT) program. They were assessed at baseline, immediately following the 5-week training period, and after 3-months using ADHD symptoms scales, as well as a series of neuropsychological tests and psychological questionnaires. Subjective ratings of everyday life attention and memory problems were also collected. The SAT group showed significant improvements in ADHD inattentive and impulsive symptoms, depressive symptoms and in self-efficacy ratings compared to the CT group at both post-training and at the 3-month assessment. Pre-post improvements in SAT participants on untrained cognitive tasks measuring selective attention and executive functions were also observed. Finally, the SAT group reported improved subjective ratings of everyday life attention at both assessment points. This pattern of results suggests that SAT may be beneficial in treating ADHD symptoms as well as psychological and cognitive impairments in adult ADHD. A large-scale randomized controlled trial (RCT) is needed.
The ability to extrapolate essential gist through the analysis and synthesis of information, prediction of potential outcomes, abstraction of ideas, and integration of relationships with world knowledge is critical for higher-order learning. The present study investigated the efficacy of cognitive training to elicit improvements in gist reasoning and fact recall ability in 556 public middle school students (grades seven and eight), vs. a sample of 357 middle school students who served as a comparison group, to determine if changes in gist reasoning and fact recall were demonstrated without cognitive training. The results showed that, in general, cognitive training increased gist reasoning and fact recall abilities in students from families in poverty as well as students from families living above poverty. However, the magnitude of gains in gist reasoning varied as a function of gender and grade level. Our primary findings were that seventh and eighth grade girls and eighth grade boys showed significant increases in gist reasoning after training regardless of socioeconomic status (SES). There were no significant increases in gist reasoning or fact recall ability for the 357 middle school students who served as a comparison group. We postulate that cognitive training in middle school is efficacious for improving gist reasoning ability and fact recall in students from all socioeconomic levels.
Background:
New effective interventions to attenuate age-related cognitive decline are a global priority. Computerized cognitive training (CCT) is believed to be safe and can be inexpensive, but neither its efficacy in enhancing cognitive performance in healthy older adults nor the impact of design factors on such efficacy has been systematically analyzed. Our aim therefore was to quantitatively assess whether CCT programs can enhance cognition in healthy older adults, discriminate responsive from nonresponsive cognitive domains, and identify the most salient design factors.
Methods and findings:
We systematically searched Medline, Embase, and PsycINFO for relevant studies from the databases' inception to 9 July 2014. Eligible studies were randomized controlled trials investigating the effects of ≥ 4 h of CCT on performance in neuropsychological tests in older adults without dementia or other cognitive impairment. Fifty-two studies encompassing 4,885 participants were eligible. Intervention designs varied considerably, but after removal of one outlier, heterogeneity across studies was small (I(2) = 29.92%). There was no systematic evidence of publication bias. The overall effect size (Hedges' g, random effects model) for CCT versus control was small and statistically significant, g = 0.22 (95% CI 0.15 to 0.29). Small to moderate effect sizes were found for nonverbal memory, g = 0.24 (95% CI 0.09 to 0.38); verbal memory, g = 0.08 (95% CI 0.01 to 0.15); working memory (WM), g = 0.22 (95% CI 0.09 to 0.35); processing speed, g = 0.31 (95% CI 0.11 to 0.50); and visuospatial skills, g = 0.30 (95% CI 0.07 to 0.54). No significant effects were found for executive functions and attention. Moderator analyses revealed that home-based administration was ineffective compared to group-based training, and that more than three training sessions per week was ineffective versus three or fewer. There was no evidence for the effectiveness of WM training, and only weak evidence for sessions less than 30 min. These results are limited to healthy older adults, and do not address the durability of training effects.
Conclusions:
CCT is modestly effective at improving cognitive performance in healthy older adults, but efficacy varies across cognitive domains and is largely determined by design choices. Unsupervised at-home training and training more than three times per week are specifically ineffective. Further research is required to enhance efficacy of the intervention. Please see later in the article for the Editors' Summary.
After a decade of waging unconventional conflicts, Defense stakeholders now generally accept that the US military has entered a new era of warfare, distinguished from previous generations by its prevalence of insurgent and terrorist tactics, frequency of non-kinetic tactical dilemmas, complexity of the sociocultural context, and emphasis on operational decentralization. To excel under such conditions, each warfighter—down to the lowest echelons—must pos-sess a high degree of cognitive readiness, that is, the mental, emotional, and interpersonal skills that allow him/her to rapidly decide and act in complex, dynamic, and ambiguous environments. Each of the US Armed Services is addressing cognitive readiness training differently. The Marine Corps, for in-stance, has embarked on two related, large-scale efforts. First, the USMC Training and Education Command (TECOM) established the Small Unit Decision Making initiative in order to "improve the ability of small unit leaders across the MAGTF to…assess, decide, and act while operating in a more decentralized manner" (Implementation Planning Guidance, p. 9). To achieve this, TECOM personnel and academic advisors are translating advanced instructional methods into actionable forms (e.g., militarized handbooks, instructor development seminars) and launching a pilot course in spring 2012 for noncommissioned officers on decision making. Second, TECOM personnel are examining instructor career progression, looking for strategies to enhance Marine Corps instructors, writ large. In other words, TECOM is looking to take Marine instructors from good to great.
Adolescents with traumatic brain injury (TBI) typically demonstrate good recovery of previously acquired skills. However, higher-order and later emergent cognitive functions are often impaired and linked to poor outcomes in academic and social/behavioral domains. Few control trials exist that test cognitive treatment effectiveness at chronic recovery stages. The current pilot study compared the effects of two forms of cognitive training, gist reasoning (top-down) versus rote memory learning (bottom-up), on ability to abstract meanings, recall facts, and utilize core executive functions (i.e., working memory, inhibition) in 20 adolescents (ages 12–20) who were 6 months or longer post-TBI. Participants completed eight 45-min sessions over 1 month. After training, the gist reasoning group (n = 10) exhibited significant improvement in ability to abstract meanings and increased fact recall. This group also showed significant generalizations to untrained executive functions of working memory and inhibition. The memory training group (n = 10) failed to show significant gains in ability to abstract meaning or on other untrained specialized executive functions, although improved fact recall approached significance. These preliminary results suggest that relatively short-term training (6 h) utilizing a top-down reasoning approach is more effective than a bottom-up rote learning approach in achieving gains in higher-order cognitive abilities in adolescents at chronic stages of TBI. These findings need to be replicated in a larger study; nonetheless, the preliminary data suggest that traditional cognitive intervention schedules need to extend to later-stage training opportunities. Chronic-stage, higher-order cognitive trainings may serve to elevate levels of cognitive performance in adolescents with TBI.
Public awareness of cognitive health is fairly recent compared to physical health. Growing evidence suggests that cognitive training offers promise in augmenting cognitive brain performance in normal and clinical populations. Targeting higher-order cognitive functions, such as reasoning in particular, may promote generalized cognitive changes necessary for supporting the complexities of daily life. This data-driven perspective highlights cognitive and brain changes measured in randomized clinical trials that trained gist reasoning strategies in populations ranging from teenagers to healthy older adults, individuals with brain injury to those at-risk for Alzheimer's disease. The evidence presented across studies support the potential for Gist reasoning training to strengthen cognitive performance in trained and untrained domains and to engage more efficient communication across widespread neural networks that support higher-order cognition. The meaningful benefits of Gist training provide compelling motivation to examine optimal dose for sustained benefits as well as to explore additive benefits of meditation, physical exercise, and/or improved sleep in future studies.
We present an evaluation of a self-administered, biofeedback-aided, alertness training programme called the Alertness: Training for Focused Living (ATFL) Programme, which was developed as part of the Technology Research for Independent Living (TRIL) collaboration. We conducted two studies in order to evaluate the programme. A randomized controlled trial was, first of all, conducted with 40 older adults aged between 60 and 83. A series of five single case studies was then conducted to examine the suitability of the programme for use with people with more severe memory difficulties. In the randomized controlled trial, participants were assigned to the ATFL Programme or to a placebo programme. Aspects of participants' memory, attention and executive functioning were assessed via telephone prior to and following completion of the training programmes and at 1, 3, and 6-month follow-up sessions. Significant improvements in sustained attention and verbal fluency were noted in the ATFL group. The series of single case studies illustrated the importance of tailoring a programme to the needs and abilities of the clients in question. The potential benefits of the ATFL programme in terms of periodically boosting alertness and aiding executive functioning are discussed.
Neuroplasticity is the remarkable ability of the brain that allows us to learn and adapt to our environment. Many studies have now shown that plasticity is retained throughout the lifespan from infancy to very old age (Merzenich et al., 1991; Merzenich and DeCharms, 1996; Greenwood and Parasuraman, 2010; May, 2011; Bavelier et al., 2012). Enriching life experiences, including literacy, prolonged engagement in the arts, sciences and music, meditation and aerobic physical activities have all been shown to engender positive neuroplasticity that boosts cognitive function and/or prevents cognitive loss (Vance et al., 2010; Hayes et al., 2013; Matta Mello Portugal et al., 2013; Newberg et al., 2013; Zatorre, 2013). Unfortunately, just as enriching experiences generate positive plasticity, negative plasticity ensues in impoverished settings. For instance, many studies now show that low socio-economic, resource-poor environments, which are associated with stress, violence and abuse within families and communities, have detrimental effects on cognition and neural function (D'Angiulli et al., 2012; McEwen and Morrison, 2013). As cognitive neuroscientists we observe both positive and negative aspects of plasticity in neural systems, in functional changes of neural activations, neural oscillations and strength of connectivity between brain regions, in structural changes in gray matter volume and white matter integrity, and importantly in the relationship between such neuroplastic changes and concomitant cognitive/behavioral changes. As we come to understand various facets of plasticity, it drives further the quest to develop new activities/interventions that engender maximal positive plasticity in selectively targeted neural systems; we envision such activities will in turn generate “far transfer of benefit” to generalized cognition and thereby improve the human condition.
Individuals often feel anxious in anticipation of tasks such as speaking in public or meeting with a boss. I find that an overwhelming majority of people believe trying to calm down is the best way to cope with pre-performance anxiety. However, across several studies involving karaoke singing, public speaking, and math performance, I investigate an alternative strategy: reappraising anxiety as excitement. Compared with those who attempt to calm down, individuals who reappraise their anxious arousal as excitement feel more excited and perform better. Individuals can reappraise anxiety as excitement using minimal strategies such as self-talk (e.g., saying "I am excited" out loud) or simple messages (e.g., "get excited"), which lead them to feel more excited, adopt an opportunity mind-set (as opposed to a threat mind-set), and improve their subsequent performance. These findings suggest the importance of arousal congruency during the emotional reappraisal process. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
Research conducted within the general paradigm of cognitive bias modification (CBM) reveals that emotional biases in attention, interpretation, and memory are not merely associated with emotional disorders but contribute to them. After briefly describing research on both emotional biases and their modification, the authors examine similarities between CBM paradigms and older experimental paradigms used in research on learning and memory. The techniques and goals of CBM research are compared with other approaches to understanding cognition-emotion interactions. From a functional perspective, the CBM tradition reminds us to use experimental tools to evaluate assumptions about clinical phenomena and, more generally, about causal relationships between cognitive processing and emotion.
© Association for Psychological Science 2011.
Complex mental activity induces improvements in cognition, brain function, and structure in animals and young adults. It is
not clear to what extent the aging brain is capable of such plasticity. This study expands previous evidence of generalized
cognitive gains after mental training in healthy seniors. Using 3 MRI-based measurements, that is, arterial spin labeling
MRI, functional connectivity, and diffusion tensor imaging, we examined brain changes across 3 time points pre, mid, and post
training (12 weeks) in a randomized sample (n = 37) who received cognitive training versus a control group. We found significant training-related brain state changes at
rest; specifically, 1) increases in global and regional cerebral blood flow (CBF), particularly in the default mode network
and the central executive network, 2) greater connectivity in these same networks, and 3) increased white matter integrity
in the left uncinate demonstrated by an increase in fractional anisotropy. Improvements in cognition were identified along
with significant CBF correlates of the cognitive gains. We propose that cognitive training enhances resting-state neural activity
and connectivity, increasing the blood supply to these regions via neurovascular coupling. These convergent results provide
preliminary evidence that neural plasticity can be harnessed to mitigate brain losses with cognitive training in seniors.
Although all professions are susceptible to work-related stress, the nursing profession has been identified as particularly stressful; indeed, oncology nursing is often described as being among the most stressful specialty areas. The current study tested the short-term effects of an innovative self-help stress management training for oncology nurses supported by mobile tools. The sample included 30 female oncology nurses with permanent status employed in six oncology hospitals in Milan, Italy. The stress inoculation training (SIT) methodology served as the basis of the training, with the innovative challenge being the use of mobile phones to support the stress management experience. To test the efficacy of the protocol, the study used a between-subjects design, comparing the experimental condition (SIT through mobile phones) with a control group (neutral video through mobile phones). The findings indicated psychological improvement of the experimental group in terms of anxiety state, anxiety trait reduction, and coping skills acquisition. This paper discusses implications for the implementation of this protocol in several contexts. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Novel therapeutic approaches and outcome data are needed for cognitive rehabilitation for patients with a traumatic brain injury; computer-based programs may play a critical role in filling existing knowledge gaps. Brain-fitness computer programs can complement existing therapies, maximize neuroplasticity, provide treatment beyond the clinic, and deliver objective efficacy data. However, these approaches have not been extensively studied in the military and traumatic brain injury population. Walter Reed National Military Medical Center established its Brain Fitness Center (BFC) in 2008 as an adjunct to traditional cognitive therapies for wounded warriors. The BFC offers commercially available "brain-training" products for military Service Members to use in a supportive, structured environment. Over 250 Service Members have utilized this therapeutic intervention. Each patient receives subjective assessments pre and post BFC participation including the Mayo-Portland Adaptability Inventory-4 (MPAI-4), the Neurobehavioral Symptom Inventory (NBSI), and the Satisfaction with Life Scale (SWLS). A review of the first 29 BFC participants, who finished initial and repeat measures, was completed to determine the effectiveness of the BFC program. Two of the three questionnaires of self-reported symptom change completed before and after participation in the BFC revealed a statistically significant reduction in symptom severity based on MPAI and NBSI total scores (p < .05). There were no significant differences in the SWLS score. Despite the typical limitations of a retrospective chart review, such as variation in treatment procedures, preliminary results reveal a trend towards improved self-reported cognitive and functional symptoms.
Current military deployments have resulted in many psychological and physical health issues and created interest in protective measures to mitigate effects of prolonged and repetitive stress. Mindfulness training has been successfully used for stress reduction in other contexts. The following case report presents a detachment of U.S. Marines who received Mindfulness-Based Mind Fitness Training (MMFT) prior to deployment. Self-report measures of mindfulness, perceptions of stress, predictors of compliance with mindfulness practice, and time spent engaging in practice were indexed. More time spent engaging in practice corresponded with greater self-reported mindfulness; increases in mindfulness were associated with decreases in perceived stress.
The ability of the human brain to learn is exceptional. Yet, learning is typically quite specific to the exact task used during training, a limiting factor for practical applications such as rehabilitation, workforce training, or education. The possibility of identifying training regimens that have a broad enough impact to transfer to a variety of tasks is thus highly appealing. This work reviews how complex training environments such as action video game play may actually foster brain plasticity and learning. This enhanced learning capacity, termed learning to learn, is considered in light of its computational requirements and putative neural mechanisms.
Improving the reasoning skills of adolescents across the United States has become a major concern for educators and scientists who are dedicated to identifying evidence-based protocols to improve student outcome. This small sample randomized, control pilot study sought to determine the efficacy of higher-order cognitive training on gist-reasoning and fact-learning in an inner-city public middle school. The study compared gist-reasoning and fact-learning performances after training in a smaller sample when tested in Spanish, many of the students’ native language, versus English. The 54 eighth grade students who participated in this pilot study were enroled in an urban middle school, predominantly from lower socio-economic status families, and were primarily of minority descent. The students were randomized into one of three groups, one that learned cognitive strategies promoting abstraction of meaning, a group that learned rote memory strategies, or a control group to ascertain the impact of each program on gist-reasoning and fact-learning from text-based information. We found that the students who had cognitive strategy instruction that entailed abstraction of meaning significantly improved their gist-reasoning and fact-learning ability. The students who learned rote memory strategies significantly improved their fact-learning scores from a text but not gist-reasoning ability. The control group showed no significant change in either gist-reasoning or fact-learning ability. A trend toward significant improvement in overall reading scores for the group that learned to abstract meaning as well as a significant correlation between gist-reasoning ability and the critical thinking on a state-mandated standardized reading test was also found. There were no significant differences between English and Spanish performance of gist-reasoning and fact-learning. Our findings suggest that teaching higher-order cognitive strategies facilitates gist-reasoning ability and student learning.
To conduct a feasibility study to compare the effects of top-down Strategic Memory and Reasoning Training (SMART) versus information-based Brain Health Workshop (BHW, control) on gist-reasoning (ie, abstracting novel meaning from complex information), memory, executive functions, and daily function in adults with traumatic brain injury.
Twenty-eight participants (of the 35 recruited), 16 men & 12 women, aged 20 to 65 years (M = 43, SD = 11.34) at chronic stages posttraumatic brain injury (2 years or longer) completed the training. Fourteen participants that received SMART and 14 participants that completed BHW were assessed both pre- and posttraining. Thirteen of the SMART trained and 11 from BHW participated in a 6-month testing.
The study was a single blinded randomized control trial. Participants in both groups received a minimum of 15 hours of training over 8 weeks.
The SMART group significantly improved gist-reasoning as compared to the BHW group. Benefits of the SMART extended to untrained measures of working memory and participation in functional activities. Exploratory analyses suggested potential transfer effects of SMART on memory and executive functions. The benefits of the SMART program as compared to BHW were evident at immediately posttraining and 6 months posttraining.
This study provides preliminary evidence that short-term intensive training in top-down modulation of information benefits gist-reasoning and generalizes to measures of executive function and real life function at chronic stages of post-TBI.
The Comprehensive Soldier Fitness (CSF) program is designed to increase psychological strength and positive performance and to reduce the incidence of maladaptive responses of the entire U.S. Army. Based on the principles of positive psychology, CSF is a historically unique approach to behavioral health in a large (1.1 million members) organization. There are four program elements: (a) the assessment of emotional, social, family, and spiritual fitness; (b) individualized learning modules to improve fitness in these domains; (c) formal resilience training; and (d) training of Army master resilience trainers (MRTs) to instill better thinking skills and resilience in their subordinates. In contrast to traditional approaches, CSF is proactive; rather than waiting to see who has a negative outcome following stress, it provides ways of improving resilience for all members of the Army. CSF aims to move the full spectrum of responses to trauma and adversity—ranging from stress-related disorders to ordinary resilience—toward personal growth. This program may provide a model for implementing similar interventions in other very large institutions.
Researchers have found that there is an increase in mental heath problems as a result of military-related traumatic events, and such problems increase in the months following return from combat. Nevertheless, researchers have not assessed the impact of early intervention efforts with this at-risk population. In the present study, the authors compared different early interventions with 2,297 U.S. soldiers following a year-long deployment to Iraq. Platoons were randomly assigned to standard postdeployment stress education, Battlemind debriefing, and small and large group Battlemind training. Results from a 4-month follow-up with 1,060 participants showed those with high levels of combat exposure who received Battlemind debriefing reported fewer posttraumatic stress symptoms, depression symptoms, and sleep problems than those in stress education. Small group Battlemind training participants with high combat exposure reported fewer posttraumatic stress symptoms and sleep problems than stress education participants. Compared to stress education participants, large group Battlemind training participants with high combat exposure reported fewer posttraumatic stress symptoms and lower levels of stigma and, regardless of combat exposure, reported fewer depression symptoms. Findings demonstrate that brief early interventions have the potential to be effective with at-risk occupational groups.
Working memory is a key function for human cognition, dependent on adequate dopamine neurotransmission. Here we show that the training of working memory, which improves working memory capacity, is associated with changes in the density of cortical dopamine D1 receptors. Fourteen hours of training over 5 weeks was associated with changes in both prefrontal and parietal D1 binding potential. This plasticity of the dopamine D1 receptor system demonstrates a reciprocal interplay between mental activity and brain biochemistry in vivo.
The objective of this prospective longitudinal study was to assess the nature, rate, predictive variables, and neuroimaging characteristics of novel (new-onset) anxiety disorders (compared with no novel anxiety disorders) 6-12 months after pediatric traumatic brain injury (TBI). Psychiatric and psychosocial interviews were administered to children who sustained mild to severe TBI at baseline (soon after injury) and at the 12-month follow-up post-injury (n = 125). The psychiatric outcome of children 12-months post-injury revealed that novel anxiety disorders present in the second six months after TBI were heterogeneous and occurred in 13 (10.4%) participants. Novel anxiety disorder was significantly associated with concurrent novel depressive disorder and with novel personality change due to TBI. Novel anxiety disorder was marginally associated with younger age at injury and with pre-injury anxiety disorder in univariate analyses. Age at injury, pre-injury anxiety disorder, and personality change due to TBI were each significantly and independently related to novel anxiety disorder in a logistic regression analysis. There were no significant neuroimaging group differences. These findings suggest that the emergence of novel anxiety disorder after TBI might be related to a broader problem of affective dysregulation especially in younger children and those with a vulnerability even to pre-injury anxiety disorder.
Decreased heart rate variability (HRV) is associated with posttraumatic stress disorder (PTSD) and depression symptoms, but PTSD's effects on the autonomic stress response and the potential influence of HRV biofeedback in stress relaxation training on improving PTSD symptoms are not well understood. The objective of this study was to examine the impact of a predeployment stress inoculation training (PRESTINT) protocol on physiologic measures of HRV in a large sample of the military population randomly assigned to experimental HRV biofeedback-assisted relaxation training versus a control condition. PRESTINT altered the parasympathetic regulation of cardiac activity, with experimental subjects exhibiting greater HRV, that is, less arousal, during a posttraining combat simulation designed to heighten arousal. Autonomic reactivity was also found to be related to PTSD and self-reported use of mental health services. Future PRESTINT training could be appropriate for efficiently teaching self-help skills to reduce the psychological harm following trauma exposure by increasing the capacity for parasympathetically modulated reactions to stress and providing a coping tool (i.e., relaxation method) for use following a stressful situation.
© 2015 Society for Psychophysiological Research.
Often, standard aphasia batteries do not fully characterize higher-order cognitive-linguistic sequelae associated with a traumatic brain injury (TBI). Limited understanding and detection of complex linguistic deficits have thwarted efforts to comprehensively remediate higher-order language deficits that persist even in chronic stages of recovery post-TBI. This chapter reviews key precursor metrics that have motivated efforts to elucidate higher-order language proficiencies after a TBI. The chapter further expounds on a paradigmatic shift away from sole focus on lower level basic skills, towards a more top-down cognitive control approach to measure, retrain, and strengthen complex language abilities in TBI. The intricate relations between complex language abilities and cognitive control functions are also discussed. The concluding section offers promising directions for future research and clinical management based on new discoveries of higher-order language impairments and their modifiability in TBI populations.
© 2015 Elsevier B.V. All rights reserved.
Objective:
This study investigated whether a stressful military training program, the 9- to 10-week U.S. Army basic combat training (BCT) course, alters the cognitive performance and mood of healthy young adult females.
Background:
Structured training programs including adolescent boot camps, sports training camps, learning enrichment programs, and military basic training are accepted methods for improving academic and social functioning. However, limited research is available on the behavioral effects of structured training programs in regard to cognitive performance and mood.
Method:
Two separate, within-subject studies were conducted with different BCT classes; in total 212 female volunteers were assessed before and after BCT. In Study 1, Four-Choice Reaction Time, Match-to-Sample, and Grammatical Reasoning tests were administered. The Psychomotor Vigilance Test (PVT) was administered in Study 2. The Profile of Mood States (POMS) was administered in both studies.
Results:
In Study 1, reaction time to correct responses on all three of the performance tests improved from pre- to post-BCT. In Study 2, PVT reaction time significantly improved. All POMS subscales improved over time in the second study, whereas POMS subscales in the first study failed to meet criteria for statistically significant differences over time.
Conclusion:
Cognition and mood substantially improved over military basic training. These changes may be a result of structured physical and mental training experienced during basic training or other factors not as yet identified.
Application:
Properly structured training may have extensive, beneficial effects on cognitive performance and mood; however, additional research is needed to determine what factors are responsible for such changes.
Background and purpose:
Vagus nerve stimulation (VNS) delivered during rehabilitative training enhances neuroplasticity and improves recovery in models of cortical ischemic stroke. However, VNS therapy has not been applied in a model of subcortical intracerebral hemorrhage (ICH). We hypothesized that VNS paired with rehabilitative training after ICH would enhance recovery of forelimb motor function beyond rehabilitative training alone.
Methods:
Rats were trained to perform an automated, quantitative measure of forelimb function. Once proficient, rats received an intrastriatal injection of bacterial collagenase to induce ICH. Rats then underwent VNS paired with rehabilitative training (VNS+Rehab; n=14) or rehabilitative training without VNS (Rehab; n=12). Rehabilitative training began ≥9 days after ICH and continued for 6 weeks.
Results:
VNS paired with rehabilitative training significantly improved recovery of forelimb function when compared with rehabilitative training without VNS. The VNS+Rehab group displayed a 77% recovery of function, whereas the Rehab group only exhibited 29% recovery. Recovery was sustained after cessation of stimulation. Both groups performed similar amounts of trials during rehabilitative, and lesion size was not different between groups.
Conclusions:
VNS paired with rehabilitative training confers significantly improved forelimb recovery after ICH compared to rehabilitative training without VNS.
The most powerful, most staggeringly complex machine ever created is all in your head. Our brain is the most adaptable, modifiable organ in our body, and yet it is the organ we most likely give the least attention. Many individuals who are concerned with having a physically fit body stop their “workout” at the neck. In the past five years brain scientists have discovered much more about how the brain works, including that it can be trained to perform better than ever before. You are never too young or too old to adopt healthy brain habits that strengthen the brain’s capacity to think smarter.
A recent study shows that the fronto-parietal network (FPN), and subregions therein, alters its functional connectivity with nodes of other networks based on task goals. Moreover, FPN patterns of connectivity not only reflect engagement of specific tasks, but also serve as a code that can be transferred to facilitate learning novel tasks.
ABSTRACT Goal-setting theory is summarized regarding the effectiveness of specific, difficult goals; the relationship of goals to affect; the mediators of goal effects; the relation of goals to self-efficacy; the moderators of goal effects; and the generality of goal effects across people, tasks, countries, time spans, experimental designs, goal sources (i.e., self-set, set jointly with others, or assigned), and dependent variables. Recent studies concerned with goal choice and the factors that influence it, the function of learning goals, the effect of goal framing, goals and affect (well-being), group goal setting, goals and traits, macro-level goal setting, and conscious versus subconscious goals are described. Suggestions are given for future research.
Data from preclinical and clinical studies have implicated the norepinephrine system in the development and maintenance of post-traumatic stress disorder. The primary source of norepinephrine in the forebrain is the locus coeruleus (LC); however, LC activity cannot be directly measured in humans, and previous research has often relied upon peripheral measures of norepinephrine to infer changes in central LC-norepinephrine function. To directly assess LC-norepinephrine function, we measured single-unit activity of LC neurons in a validated rat model of post-traumatic stress disorder - single prolonged stress (SPS). We also examined tyrosine hydroxylase mRNA levels in the LC of SPS and control rats as an index of norepinephrine utilisation. For electrophysiological recordings, 92 LC neurons were identified from 19 rats (SPS, 12; control, 7), and spontaneous and evoked responses to a noxious event (paw compression) were recorded. Baseline and restraint stress-evoked tyrosine hydroxylase mRNA expression levels were measured in SPS and control rats (n = 16 per group) in a separate experiment. SPS rats showed lower spontaneous activity but higher evoked responses, leading to an enhanced signal-to-noise ratio of LC neurons, accompanied by impaired recovery from post-stimulus inhibition. In concert, tyrosine hydroxylase mRNA expression in the LC of SPS rats tended to be lower at baseline, but was exaggerated following restraint stress. These data demonstrate persistent changes in LC function following stress/trauma in a rat model of post-traumatic stress, as measured by differences in both the electrophysiological properties of LC neurons and tyrosine hydroxylase mRNA transcription.
Working memory (WM) training (WMT) alters the task-related brain activity and structure of the external attention system (EAS). We investigated whether WMT also alters resting-state brain mechanisms, which are assumed to reflect intrinsic brain activity and connectivity. Our study subjects were subjected to a 4-week WMT program and brain scans before and after the intervention for determining changes of functional connectivity and regional cerebral blood flow during rest (resting-FC/resting-rCBF). Compared with no-intervention, WMT (a) increased resting-FC between the medial prefrontal cortex (mPFC) and precuneus, which are key nodes of the default mode network (DMN), (b) decreased resting-FC between mPFC and the right posterior parietal cortex/right lateral prefrontal cortex (LPFC), which are key nodes of the EAS, and (c) increased resting-rCBF in the right LPFC. However, the training-related decreases in resting-FC between the key DMN node and the nodes of EAS were only observed when the whole brain signal was regressed out in individual analyses, and these changes were not observed when the whole brain signal was not regressed out in individual analyses. Further analyses indicated that these differences may be mediated by a weak but a widespread increase in resting-FC between the nodes of EAS and activity of multiple bilateral areas across the brain. These results showed that WMT induces plasticity in neural mechanisms involving DMN and the EAS during rest and indicated that intrinsic brain activity and connectivity can be affected by cognitive training.
Chronic stress could trigger maladaptive changes associated with stress-related mental disorders; however, the underlying mechanisms remain elusive. In this study, we found that exposing juvenile male rats to repeated stress significantly impaired the temporal order recognition memory, a cognitive process controlled by the prefrontal cortex (PFC). Concomitantly, significantly reduced AMPAR- and NMDAR-mediated synaptic transmission and glutamate receptor expression were found in PFC pyramidal neurons from repeatedly stressed animals. All these effects relied on activation of glucocorticoid receptors and the subsequent enhancement of ubiquitin/proteasome-mediated degradation of GluR1 and NR1 subunits, which was controlled by the E3 ubiquitin ligase Nedd4-1 and Fbx2, respectively. Inhibition of proteasomes or knockdown of Nedd4-1 and Fbx2 in PFC prevented the loss of glutamatergic responses and recognition memory in stressed animals. Our results suggest that repeated stress dampens PFC glutamatergic transmission by facilitating glutamate receptor turnover, which causes the detrimental effect on PFC-dependent cognitive processes.
The study examined the accumulated as well as the differential influence of negative life events on cognitive decline in older persons, and whether this association was different for persons with normal and poor cognitive functioning, and for ApoE ε4 carriers and noncarriers.
We used data from the Longitudinal Aging Study Amsterdam (N = 1,356). Data were analyzed using linear mixed models.
We found differential associations for different negative life events with cognitive decline none of which were mediated by depressive symptoms. The death of a child or grandchild, which may be considered a highly stressful event, was associated to a higher rate of cognitive decline, whereas more chronic stressors, such as the illness of a partner or relative, or serious conflicts, were associated with better cognitive function. The associations between life events and cognitive function were stronger in ApoE ε4 carriers compared with noncarriers, suggesting that this gene plays a role in the association between stress and cognitive function.
Highly stressful events seem to be associated with a higher rate of cognitive decline, whereas mild chronic stressors may have an arousing function that stimulates cognitive performance.
To test the effects of cognitive training on subsequent motor vehicle collision (MVC) involvement of older drivers.
Randomized, controlled, multisite, single-blind clinical trial.
Community-dwelling seniors at four U.S. sites: Birmingham, Alabama; Baltimore, Maryland; Indianapolis, Indiana; and State College, Pennsylvania.
Nine hundred eight older drivers (mean age 73.1; 18.6% African American) who were randomized to one of three cognitive interventions or a control condition.
Up to 10 sessions of cognitive training for memory, reasoning, or speed of processing.
State-recorded MVC involvement up to 6 years after study enrollment.
Speed-of-processing and reasoning training resulted in lower rates of at-fault collision involvement over the subsequent approximately 6-year period than controls. After adjusting for age, sex, race, education, mental status, health, vision, depressive symptoms, and testing site, participants randomized to the speed-of-processing and reasoning interventions had an approximately 50% lower rate (per person-mile) of at-fault MVCs than the control group (rate ratio (RR) = 0.57, 95% confidence interval (CI) = 0.34-0.96 for speed of processing), and (RR = 0.50, 95% CI = 0.27-0.92 for reasoning). There was no significant difference observed for the memory group.
Cognitive speed-of-processing and reasoning training resulted in a lower at-fault MVC rate in older drivers than in controls. Considering the importance of driving mobility, the costs of crashes, and the benefits of cognitive training, these interventions have great potential to sustain independence and quality of life of older adults. More research is needed to understand the effects of different types and quantities of training.
Cognitive impairment is a key factor that threatens functionality and quality of life in seniors. Given the projection that the population of individuals 65 years of age and older will double within the next 25 years, a critical need exists to identify and test effectiveness of protocols that target higher-order cognitive skills such as gist reasoning to maximize cognitive capacity in later life.
This study examined the effects of eight hours of gist reasoning training in 26 cognitively normal seniors between the ages of 64-85 years (M = 74.23, SD = 6.67).
Findings suggest that top-down strategy-based gist reasoning training significantly improved abstraction ability, a skill relevant to everyday life, as well as generalized to untrained measures of executive function including concept abstraction, cognitive switching, and verbal fluency. Individuals with lower baseline ability to abstract gist showed the greatest gain in the target domain trained.
These findings highlight the potential value of engaging in cognitively challenging activities that involve gist reasoning, to strengthen and preserve cognitive capacity with aging.
Trauma to the brain can change the core of a person's being—their thinking, memory, personality, and behavior. Although individuals who have suffered traumatic brain injury (TBI) may feel alone in their struggle to deal with the aftermath of injury, they actually join the ranks of those affected by one of the most common neurological diagnoses in the United States (Rutland-Brown et al., 2006). TBI affects every age group and segment of society. Recent combat-related activities have increased the incidence of TBI as well as piqued the attention of the public and elected representatives. Concussions suffered during sports activities have been a major issue for years and are only now receiving widespread coverage in the news media with high-profile cases. Undoubtedly, many more individuals have suffered brain injury than are diagnosed. Changes in society and advances in neuroscience make it worthwhile to re-examine the scope of the problem, neural mechanisms underlying the cognitive and behavioral deficits of this disorder, and approaches that can be taken to help individuals that have suffered from TBI heal. We highlight several major paradigm shifts that must occur for the field to advance.
To describe the most recent estimates of the incidence and prevalence of traumatic brain injury (TBI) and review current issues related to measurement and use of these data.
State of the science literature for the United States and abroad was analyzed and issues were identified for (1) incidence of TBI, (2) prevalence of lifetime history of TBI, and (3) incidence and prevalence of disability associated with TBI.
The most recent estimates indicate that each year 235 000 Americans are hospitalized for nonfatal TBI, 1.1 million are treated in emergency departments, and 50 000 die. The northern Finland birth cohort found that 3.8% of the population had experienced at least 1 hospitalization due to TBI by 35 years of age. The Christchurch New Zealand birth cohort found that by 25 years of age 31.6% of the population had experienced at least 1 TBI, requiring medical attention (hospitalization, emergency department, or physician office). An estimated 43.3% of Americans have residual disability 1 year after hospitalization with TBI. [corrected] The most recent estimate of the prevalence of US civilian residents living with disability following hospitalization with TBI is 3.2 million.
Estimates of the incidence and prevalence of TBI are based on varying sources of data, methods of calculation, and assumptions. Informed users should be cognizant of the limitations of these estimates when determining their applicability.
To investigate the efficacy of a novel brain plasticity-based computerized cognitive training program in older adults and to evaluate the effect on untrained measures of memory and attention and participant-reported outcomes.
Multisite randomized controlled double-blind trial with two treatment groups.
Communities in northern and southern California and Minnesota.
Community-dwelling adults aged 65 and older (N=487) without a diagnosis of clinically significant cognitive impairment.
Participants were randomized to receive a broadly-available brain plasticity-based computerized cognitive training program (intervention) or a novelty- and intensity-matched general cognitive stimulation program modeling treatment as usual (active control). Duration of training was 1 hour per day, 5 days per week, for 8 weeks, for a total of 40 hours.
The primary outcome was a composite score calculated from six subtests of the Repeatable Battery for the Assessment of Neuropsychological Status that use the auditory modality (RBANS Auditory Memory/Attention). Secondary measures were derived from performance on the experimental program, standardized neuropsychological assessments of memory and attention, and participant-reported outcomes.
RBANS Auditory Memory/Attention improvement was significantly greater (P=.02) in the experimental group (3.9 points, 95% confidence interval (CI)=2.7-5.1) than in the control group (1.8 points, 95% CI=0.6-3.0). Multiple secondary measures of memory and attention showed significantly greater improvements in the experimental group (word list total score, word list delayed recall, digits backwards, letter-number sequencing; P<.05), as did the participant-reported outcome measure (P=.001). No advantage for the experimental group was seen in narrative memory.
The experimental program improved generalized measures of memory and attention more than an active control program.
Traumatic brain injury (TBI) is a common occurrence, with a rate of nearly 400,000 new injuries per year. Cognitive and emotional disturbances may become persistent and disabling for many injured persons, and frequently involve symptomatic impairment in attention and memory. Impairments in attention and memory have been well characterized in TBI, and are likely related to disruption of cholinergic functioning in the hippocampus. Additionally, disturbances in this neurotransmitter system may also account for disturbances in sensory gating and discriminative attention in this population. The electroencephalographic P50 waveform of the evoked response to paired auditory stimuli may provide a physiologic market of impaired sensory gating among TBI survivors. The first application of this recording assessment to the TBI population is reported. Preliminary findings in three cases are presented, and the interpretation of impaired sensory gating in this population is discussed. Given the impact of TBI on cholinergic systems, the effects of cholinergic augmentation on attention and memory impairment, and the availability of an electrophysiologic marker of cholinergic dysfunction responsive to cholinergic agents, a testable cholinergic hypothesis for investigation and treatment of these patients is proposed.