Cognitive and Salience Network Connectivity Changes following a Single Season of Repetitive Head Impact Exposure in High School Football.

BACKGROUND AND PURPOSE: During a season of high school football, adolescents with actively developing brains experience a considerable number of head impacts. Our aim was to determine whether repetitive head impacts in the absence of a clinically diagnosed concussion during a season of high school football produce changes in cognitive performance or functional connectivity of the salience network and its central hub, the dorsal anterior cingulate cortex. MATERIALS AND METHODS: Football players were instrumented with the Head Impact Telemetry System during all practices and games, and the helmet sensor data were used to compute a risk-weighted exposure metric (RWEcp), accounting for the cumulative risk during the season. Participants underwent MRI and a cognitive battery (ImPACT) before and shortly after the football season. A control group of noncontact/limited-contact-sport athletes was formed from 2 cohorts: one from the same school and protocol and another from a separate, nearly identical study. RESULTS: Sixty-three football players and 34 control athletes were included in the cognitive performance analysis. Preseason, the control group scored significantly higher on the ImPACT Visual Motor (P = .04) and Reaction Time composites (P = .006). These differences increased postseason (P = .003, P < .001, respectively). Additionally, the control group had significantly higher postseason scores on the Visual Memory composite (P = .001). Compared with controls, football players showed significantly less improvement in the Verbal (P = .04) and Visual Memory composites (P = .01). A significantly greater percentage of contact athletes had lower-than-expected scores on the Verbal Memory (27% versus 6%), Visual Motor (21% versus 3%), and Reaction Time composites (24% versus 6%). Among football players, a higher RWEcp was significantly associated with greater increments in ImPACT Reaction Time (P = .03) and Total Symptom Scores postseason (P = .006). Fifty-seven football players and 13 control athletes were included in the imaging analyses. Postseason, football players showed significant decreases in interhemispheric connectivity of the dorsal anterior cingulate cortex (P = .026) and within-network connectivity of the salience network (P = .018). These decreases in dorsal anterior cingulate cortex interhemispheric connectivity and within-network connectivity of the salience network were significantly correlated with deteriorating ImPACT Total Symptom (P = .03) and Verbal Memory scores (P = .04). CONCLUSIONS: Head impact exposure during a single season of high school football is negatively associated with cognitive performance and brain network connectivity. Future studies should further characterize these short-term effects and examine their relationship with long-term sequelae.

Use of magnetic source imaging to assess recovery after severe traumatic brain injury-an MEG pilot study.

Rationale: Severe TBI (sTBI) is a devastating neurological injury that comprises a significant global trauma burden. Early comprehensive neurocritical care and rehabilitation improve outcomes for such patients, although better diagnostic and prognostic tools are necessary to guide personalized treatment plans. Methods: In this study, we explored the feasibility of conducting resting state magnetoencephalography (MEG) in a case series of sTBI patients acutely after injury (~7 days), and then about 1.5 and 8 months after injury. Synthetic aperture magnetometry (SAM) was utilized to localize source power in the canonical frequency bands of delta, theta, alpha, beta, and gamma, as well as DC-80 Hz. Results: At the first scan, SAM source maps revealed zones of hypofunction, islands of preserved activity, and hemispheric asymmetry across bandwidths, with markedly reduced power on the side of injury for each patient. GCS scores improved at scan 2 and by scan 3 the patients were ambulatory. The SAM maps for scans 2 and 3 varied, with most patients showing increasing power over time, especially in gamma, but a continued reduction in power in damaged areas and hemispheric asymmetry and/or relative diminishment in power at the site of injury. At the group level for scan 1, there was a large excess of neural generators operating within the delta band relative to control participants, while the number of neural generators for beta and gamma were significantly reduced. At scan 2 there was increased beta power relative to controls. At scan 3 there was increased group-wise delta power in comparison to controls. Conclusion: In summary, this pilot study shows that MEG can be safely used to monitor and track the recovery of brain function in patients with severe TBI as well as to identify patient-specific regions of decreased or altered brain function. Such MEG maps of brain function may be used in the future to tailor patient-specific rehabilitation plans to target regions of altered spectral power with neurostimulation and other treatments.

Pilot characterization of head kinematics in grassroots dirt track racing.

OBJECTIVE: The objective of this study was to utilize an instrumented mouthpiece sensor to characterize head kinematics experienced by grassroots dirt track race car drivers. METHODS: Four dirt track race car drivers (ages 16-19) were instrumented with custom mouthpiece sensors capable of accurately measuring head motion during racing. Sensors were deployed before races and recorded tri-axial linear acceleration and rotational velocity for approximately 10 min at 200 Hz. Film review was performed to identify data associated with racing laps. For each lap, moving average kinematics were computed and subtracted from the head motion signals to obtain 'adjusted' head motion accounting for lower frequency variance due to periodic motion around the track. From adjusted data, linear and angular head perturbations (i.e., deviations from moving average) were extracted using a custom algorithm. RESULTS: Data was collected during 400 driver-races. A total of 2438 laps were segmented from mouthpiece recordings. The median (95th percentile) peak linear acceleration, rotational velocity, and rotational acceleration of all laps were 5.33 (8.28) g, 2.89 (4.60) rad/s, and 179 (310) rad/s2, respectively. Angular perturbations occurred most frequently about the anterior-posterior axis (median lap frequency = 6.39 Hz); whereas linear perturbations occurred most frequently in the inferior-superior direction (7.96 Hz). Nine crash events were recorded by the mouthpiece sensors. The median (95th percentile) peak head kinematics of these events were 13.4 (36.6) g, 9.67 (21.9) rad/s, and 630 (1330) rad/s2. CONCLUSIONS: Mouthpiece sensors can be used to measure head kinematics during active racing. Laps, head perturbations, and crashes may be useful units of observation to describe typical head kinematic exposure experienced by drivers while racing. Subsequent research is needed to understand the associations between repetitive racing exposure and neurological function. Higher magnitude events (i.e., crashes) are not uncommon and may result in concussion or more severe injury. Results represent novel characterizations of head kinematic exposure experienced in a dirt track racing environment. This information may inform evidence-based strategies (e.g., vehicle/seat design) to improve driver safety.

Stability of Subjective Executive Functioning in Older Adults with aMCI and Subjective Cognitive Decline.

OBJECTIVE: Subjective memory concerns are characteristic of individuals with amnestic mild cognitive impairment (aMCI) and subjective cognitive decline (SCD), though subjective changes in executive functions have also been reported. In a cohort study, we examined the temporal stability of subjective report of executive functioning in a high education (mean = 16.8 years) sample of cognitively normal (CN) older adults and those with aMCI or SCD. METHOD: Participants (CN, n = 22; aMCI, n = 21; SCD, n = 24) and their informants completed the BRIEF-A and neuropsychological tests at two time points separated by approximately 1 year. RESULTS: Analyses focused on those with diagnostic stability (95.7%). Participants with aMCI and SCD, and their informants, endorsed worse executive functions relative to CN at both time points. No group by time interaction was observed for subjective or objective measures of executive function. CONCLUSIONS: Diagnostically stable CN older adults, and those with prodromal dementia conditions, report stable executive functioning at 1-year follow-up.

Differential Effects of Pergolide and Bromocriptine on Working Memory Performance and Brain Activation after Mild Traumatic Brain Injury.

Dopamine D1 and D2 receptors differ with respect to patterns of regional brain distribution and behavioral effects. Pre-clinical work suggests that D1 agonists enhance working memory, but the absence of selective D1 agonists has constrained using this approach in humans. This study examines working memory performance in mild traumatic brain injury (mTBI) patients when given pergolide, a mixed D1/D2 agonist, compared with bromocriptine, a selective D2 agonist. Fifteen individuals were studied 1 month after mTBI and compared with 17 healthy controls. At separate visits, participants were administered 1.25 mg bromocriptine or 0.05 mg pergolide prior to functional magnetic resonance imaging (MRI) using a working memory task (visual-verbal n-back). Results indicated a significant group-by-drug interaction for mean performance across n-back task conditions, where the mTBI group showed better performance on pergolide relative to bromocriptine, whereas controls showed the opposite pattern. There was also a significant effect of diagnosis, where mTBI patients performed worse than controls, particularly while on bromocriptine, as shown in our prior work. Functional MRI activation during the most challenging task condition (3-back > 0-back contrast) showed a significant group-by-drug interaction, with the mTBI group showing increased activation relative to controls in working memory circuitry while on pergolide, including in the left inferior frontal gyrus. Across participants there was a positive correlation between change in activation in this region and change in performance between drug conditions. Results suggest that activation of the D1 receptor may improve working memory performance after mTBI. This has implications for the development of pharmacological strategies to treat cognitive deficits after mTBI.

Comparison of season-long diffusivity measures in a cohort of non-concussed contact and non-contact athletes.

INTRODUCTION: Concern surrounding short- and long-term consequences of participation in contact sports has become a significant public health topic. Previous literature utilizing diffusion tensor imaging in sports-related concussion has exhibited notable variety of analysis methods and analyzed regions of interest, and largely focuses on acute effects of concussion. The current study aimed to compare diffusivity metrics across a single season within athlete cohorts with no history of concussion. METHODS: A prospective cohort of 75 contact and 79 non-contact division I athletes were compared across diffusion tensor imaging metrics (i.e. TRACULA); examinations were also performed assessing the relationship between neuroimaging metrics, head impact exposure metrics (in-helmet accelerometer), and neurocognitive variables. Assessment occurred at pre-and post-season time points. RESULTS: Seasonal changes in fractional anisotropy and mean diffusivity values did not differ between athlete cohorts, nor did they differ within cohort groups, across pre- and post-season scans. Specific to contact athletes, positive associations were found between uncinate fasciculus mean diffusivity values and season linear acceleration (p =.018), season rotational acceleration (p =.017), and season hit severity (p =.021). CONCLUSIONS: Results suggest an influence of impact frequency, type, and severity on white matter integrity in select brain regions in contact athletes. Current findings expand our knowledge of anatomical changes over the course of a single season, and underscore the importance of considering methodology when interpreting findings in this population, as differing image analysis techniques may lead to different conclusions regarding significant effects.

Contributions of posttraumatic stress disorder (PTSD) and mild TBI (mTBI) history to suicidality in the INTRuST consortium.

OBJECTIVE: Mild TBI (mTBI) and posttraumatic stress disorder (PTSD) are independent risk factors for suicidal behaviour (SB). Further, co-occurring mTBI and PTSD increase one's risk for negative health and psychiatric outcomes. However, little research has examined the role of comorbid mTBI and PTSD on suicide risk. METHODS: The present study utilized data from the Injury and TRaUmatic STress (INTRuST) Consortium to examine the prevalence of suicidal ideation (SI) and behaviours among four groups: 1) comorbid mTBI+PTSD, 2) PTSD only, 3) mTBI only, and 4) healthy controls. RESULTS: Prevalence of lifetime SI, current SI, and lifetime SB for individuals with mTBI+PTSD was 40%, 25%, and 19%, respectively. Prevalence of lifetime SI, current SI, and lifetime SB for individuals with PTSD only was 29%, 11%, and 11%, respectively. Prevalence of lifetime SI, current SI, and lifetime SB for individuals with mTBI only was 14%, 1%, and 2%, respectively. Group comparisons showed that individuals with mTBI alone experienced elevated rates of lifetime SI compared to healthy controls. History of mTBI did not add significantly to risk for suicidal ideation and behaviour beyond what is accounted for by PTSD. CONCLUSION: Findings suggest that PTSD seems to be driving risk for suicidal behaviour.

Associations between neuropsychiatric and health status outcomes in individuals with probable mTBI.

Mild traumatic brain injury (mTBI) is a common occurrence, and may impact distal outcomes in a subgroup of individuals. Improved characterization of health outcomes and identification of factors associated with poor outcomes is needed to better understand the impact of mTBI, particularly in those with co-occurring posttraumatic stress disorder (PTSD). Participants in a data repository of the Injury and Traumatic Stress (INTRuST) Clinical Consortium (n = 625) completed functional disability [FD] and health-related quality of life [HRQOL] questionnaires, and a subset completed a neuropsychological assessment. FD and HRQOL were compared among participants with probable mTBI (mTBI), probable mTBI with PTSD (mTBI/PTSD), and health comparison participants (HC). Associations between symptoms, neuropsychological performance, and health outcomes were examined in those with probable mTBI with and without PTSD (n = 316). Individuals in the mTBI/PTSD group endorsed poorer health outcomes than those in the mTBI group, who endorsed poorer outcomes than those in the HC group. Individuals in either mTBI group performed worse than those in the HC on verbal learning and memory and psychomotor speed. Health outcomes were correlated with mental health and postconcussive symptoms, as well as neuropsychological variables. mTBI may adversely impact self-reported health, with the greatest effect observed in individuals with co-occurring mTBI/PTSD.

Hybrid Diffusion Imaging in Mild Traumatic Brain Injury.

Mild traumatic brain injury (mTBI) is an important public health problem. Although conventional medical imaging techniques can detect moderate-to-severe injuries, they are relatively insensitive to mTBI. In this study, we used hybrid diffusion imaging (HYDI) to detect white matter alterations in 19 patients with mTBI and 23 other trauma control patients. Within 15 days (standard deviation = 10) of brain injury, all subjects underwent magnetic resonance HYDI and were assessed with a battery of neuropsychological tests of sustained attention, memory, and executive function. Tract-based spatial statistics (TBSS) was used for voxel-wise statistical analyses within the white matter skeleton to study between-group differences in diffusion metrics, within-group correlations between diffusion metrics and clinical outcomes, and between-group interaction effects. The advanced diffusion imaging techniques, including neurite orientation dispersion and density imaging (NODDI) and q-space analyses, appeared to be more sensitive then classic diffusion tensor imaging. Only NODDI-derived intra-axonal volume fraction (Vic) demonstrated significant group differences (i.e., 5-9% lower in the injured brain). Within the mTBI group, Vic and a q-space measure, P0, correlated with 6 of 10 neuropsychological tests, including measures of attention, memory, and executive function. In addition, the direction of correlations differed significantly between groups (R2 > 0.71 and pinteration < 0.03). Specifically, in the control group, higher Vic and P0 were associated with better performances on clinical assessments, whereas in the mTBI group, higher Vic and P0 were associated with worse performances with correlation coefficients >0.83. In summary, the NODDI-derived axonal density index and q-space measure for tissue restriction demonstrated superior sensitivity to white matter changes shortly after mTBI. These techniques hold promise as a neuroimaging biomarker for mTBI.

Multi-site harmonization of diffusion MRI data in a registration framework.

Diffusion MRI (dMRI) data acquired on different scanners varies significantly in its content throughout the brain even if the acquisition parameters are nearly identical. Thus, proper harmonization of such data sets is necessary to increase the sample size and thereby the statistical power of neuroimaging studies. In this paper, we present a novel approach to harmonize dMRI data (the raw signal, instead of dMRI derived measures such as fractional anisotropy) using rotation invariant spherical harmonic (RISH) features embedded within a multi-modal image registration framework. All dMRI data sets from all sites are registered to a common template and voxel-wise differences in RISH features between sites at a group level are used to harmonize the signal in a subject-specific manner. We validate our method on diffusion data acquired from seven different sites (two GE, three Philips, and two Siemens scanners) on a group of age-matched healthy subjects. We demonstrate the efficacy of our method by statistically comparing diffusion measures such as fractional anisotropy, mean diffusivity and generalized fractional anisotropy across these sites before and after data harmonization. Validation was also done on a group oftest subjects, which were not used to "learn" the harmonization parameters. We also show results using TBSS before and after harmonization for independent validation of the proposed methodology. Using synthetic data, we show that any abnormality in diffusion measures due to disease is preserved during the harmonization process. Our experimental results demonstrate that, for nearly identical acquisition protocol across sites, scanner-specific differences in the signal can be removed using the proposed method in a model independent manner.

White matter abnormalities in mild traumatic brain injury with and without post-traumatic stress disorder: a subject-specific diffusion tensor imaging study.

Mild traumatic brain injuries (mTBIs) are often associated with posttraumatic stress disorder (PTSD). In cases of chronic mTBI, accurate diagnosis can be challenging due to the overlapping symptoms this condition shares with PTSD. Furthermore, mTBIs are heterogeneous and not easily observed using conventional neuroimaging tools, despite the fact that diffuse axonal injuries are the most common injury. Diffusion tensor imaging (DTI) is sensitive to diffuse axonal injuries and is thus more likely to detect mTBIs, especially when analyses account for the inter-individual variability of these injuries. Using a subject-specific approach, we compared fractional anisotropy (FA) abnormalities between groups with a history of mTBI (n = 35), comorbid mTBI and PTSD (mTBI + PTSD; n = 22), and healthy controls (n = 37). We compared all three groups on the number of abnormal FA clusters derived from subject-specific injury profiles (i.e., individual z-score maps) along a common white matter skeleton. The mTBI + PTSD group evinced a greater number of abnormally low FA clusters relative to both the healthy controls and the mTBI group without PTSD (p < .05). Across the groups with a history of mTBI, increased numbers of abnormally low FA clusters were significantly associated with PTSD symptom severity, depression, post-concussion symptoms, and reduced information processing speed (p < .05). These findings highlight the utility of subject-specific microstructural analyses when searching for mTBI-related brain abnormalities, particularly in patients with PTSD. This study also suggests that patients with a history of mTBI and comorbid PTSD, relative to those without PTSD, are at increased risk of FA abnormalities.

Effects of Transcranial Magnetic Stimulation on the Cognitive Control of Emotion: Potential Antidepressant Mechanisms.

Depression negatively impacts quality of life and is associated with high mortality rates. Recent research has demonstrated that improvement in depression symptoms with transcranial magnetic stimulation (TMS) to the dorsolateral prefrontal cortex (DLPFC) may involve changes in the cognitive control network, a regulatory system modulating the function of cognitive and emotional systems, composed of the DLPFC, dorsal anterior cingulate, and posterior parietal cortices. Transcranial magnetic stimulation to the DLPFC node of the cognitive control network may have antidepressant efficacy via direct effects on cognitive control processes involved in emotion regulation. This review provides a review of the impact of TMS on cognitive control processes, especially those related to emotion regulation, and posits that these effects are critical to the mechanism of action of TMS for depression. Treatment implications and future directions for study are discussed.

Randomized controlled trial of acceptance and commitment therapy for distress and impairment in OEF/OIF/OND veterans.

OBJECTIVE: Acceptance and commitment therapy (ACT) is a widely utilized psychotherapeutic approach, but randomized, controlled studies are lacking in veterans. This study evaluated the efficacy of ACT for emotional distress among veterans of the conflicts in Iraq and Afghanistan. METHOD: One hundred sixty veterans (80% male, Mage = 34 years) with anxiety or depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) were randomized to ACT or present-centered therapy (PCT) and assessed before, during, and after treatment and during 3- to 12-month follow-up. The primary outcome was general distress as measured by the Brief Symptom Inventory-18 Global Severity Index. Additional outcomes included symptomatology, disability, quality of life, acceptability, and satisfaction. RESULTS: There was improvement following treatment in the whole sample across a variety of measures, including general distress (d = 0.74, 95% confidence interval [CI: 0.52, 0.96]) and functioning (d = 0.71, 95% CI [0.50, 0.93]) and moderate to high levels of satisfaction with treatment. Response to the 2 interventions did not differ on the primary outcome or most secondary outcomes, although ACT led to greater improvement in insomnia than did PCT (ds = 0.63 and 0.08, respectively). Treatment dropout did not differ by condition but was high (41.9%). CONCLUSIONS: ACT's efficacy in this group was modest and generally did not differ from that for PCT. Additional work is needed to understand the reasons that ACT did not perform as well as predicted in this veteran sample. (PsycINFO Database Record

Understanding the interplay between mild traumatic brain injury and cognitive fatigue: models and treatments.

Nearly 2 million traumatic brain injuries occur annually, most of which are mild (mTBI). One debilitating sequela of mTBI is cognitive fatigue: fatigue following cognitive work. Cognitive fatigue has proven difficult to quantify and study, but this is changing, allowing models to be proposed and tested. Here, we review evidence for four models of cognitive fatigue, and relate them to specific treatments following mTBI. The evidence supports two models: cognitive fatigue results from the increased work/effort required for the brain to process information after trauma-induced damage; and cognitive fatigue results from sleep disturbances. While there are no evidence-based treatments for fatigue after mTBI, some pharmacological and nonpharmacological treatments show promise for treating this debilitating problem. Future work may target the role of genetics, neuroinflammation and the microbiome and their role in complex cognitive responses such as fatigue.

Methylphenidate and Memory and Attention Adaptation Training for Persistent Cognitive Symptoms after Traumatic Brain Injury: A Randomized, Placebo-Controlled Trial.

The purpose of this multicenter, prospective, randomized, placebo-controlled study was to evaluate and compare the efficacy of two cognitive rehabilitation interventions (Memory and Attention Adaptation Training (MAAT) and Attention Builders Training (ABT)), with and without pharmacological enhancement (ie, with methylphenidate (MPH) or placebo), for treating persistent cognitive problems after traumatic brain injury (TBI). Adults with a history of TBI at least 4 months before study enrollment with either objective cognitive deficits or subjective cognitive complaints were randomized to receive MPH or placebo and MAAT or ABT, yielding four treatment combinations: MAAT/MPH (N=17), ABT/MPH (N=19), MAAT/placebo (N=17), and ABT/placebo (N=18). Assessments were conducted pre-treatment (baseline) and after 6 weeks of treatment (post treatment). Outcome measures included scores on neuropsychological measures and subjective rating scales. Statistical analyses used linear regression models to predict post-treatment scores for each outcome variable by treatment type, adjusting for relevant covariates. Statistically significant (P<0.05) treatment-related improvements in cognitive functioning were found for word-list learning (MAAT/placebo>ABT/placebo), nonverbal learning (MAAT/MPH>MAAT/placebo and MAAT/MPH>ABT/MPH), and auditory working memory and divided attention (MAAT/MPH>ABT/MPH). These results suggest that combined treatment with metacognitive rehabilitation (MAAT) and pharmacotherapy (MPH) can improve aspects of attention, episodic and working memory, and executive functioning after TBI.

CVLT-II Forced Choice Recognition Trial as an Embedded Validity Indicator: A Systematic Review of the Evidence.

OBJECTIVES: The Forced Choice Recognition (FCR) trial of the California Verbal Learning Test, 2nd edition, was designed as an embedded performance validity test (PVT). To our knowledge, this is the first systematic review of classification accuracy against reference PVTs. METHODS: Results from peer-reviewed studies with FCR data published since 2002 encompassing a variety of clinical, research, and forensic samples were summarized, including 37 studies with FCR failure rates (N=7575) and 17 with concordance rates with established PVTs (N=4432). RESULTS: All healthy controls scored >14 on FCR. On average, 16.9% of the entire sample scored ≤14, while 25.9% failed reference PVTs. Presence or absence of external incentives to appear impaired (as identified by researchers) resulted in different failure rates (13.6% vs. 3.5%), as did failing or passing reference PVTs (49.0% vs. 6.4%). FCR ≤14 produced an overall classification accuracy of 72%, demonstrating higher specificity (.93) than sensitivity (.50) to invalid performance. Failure rates increased with the severity of cognitive impairment. CONCLUSIONS: In the absence of serious neurocognitive disorder, FCR ≤14 is highly specific, but only moderately sensitive to invalid responding. Passing FCR does not rule out a non-credible presentation, but failing FCR rules it in with high accuracy. The heterogeneity in sample characteristics and reference PVTs, as well as the quality of the criterion measure across studies, is a major limitation of this review and the basic methodology of PVT research in general. (JINS, 2016, 22, 851-858).

Alpha-synuclein (SNCA) polymorphisms exert protective effects on memory after mild traumatic brain injury.

Problems with attention and short-term learning and memory are commonly reported after mild traumatic brain injury (mTBI). Due to the known relationships between α-synuclein (SNCA), dopaminergic transmission, and neurologic deficits, we hypothesized that SNCA polymorphisms might be associated with cognitive outcome after mTBI. A cohort of 91 mTBI patients one month after injury and 86 healthy controls completed a series of cognitive tests assessing baseline intellectual function, attentional function, and memory, and was genotyped at 13 common single nucleotide polymorphisms (SNPs) in the SNCA gene. Significant differences in two memory measures (p=0.001 and 0.002), but not baseline intellectual function or attentional function tasks, were found between the mTBI group and controls. A highly significant protective association between memory performance and SNCA promoter SNP rs1372525 was observed in the mTBI patients (p=0.006 and 0.029 for the long and short delay conditions of the California Verbal Learning Tests, respectively), where the presence of at least one copy of the A (minor) allele was protective after mTBI. These results may help elucidate the pathophysiology of cognitive alterations after mTBI, and thus warrant further investigation.

Investigating social cognition in epilepsy using a naturalistic task.

OBJECTIVE: The primary objective for this study was to assess social cognition in patients with focal epilepsy using a naturalistic task, which accurately models complex real-world social interaction. METHODS: We conducted an observational study of social cognition in 43 patients with focal epilepsy and in 22 controls. Patients and controls completed The Awareness of Social Inference Test, which measures both basic and advanced social cognition in a realistic video-based format. Patient and controls also completed standard measures of cognitive functioning and measures of depression. RESULTS: Compared to controls, we found that patients with epilepsy (PWEs) had no difficulty identifying positively valenced emotional states (happiness) yet had difficulty identifying most negatively valenced emotional states (anger, fear, and disgust). In addition, PWEs were able to identify sincere exchanges correctly but could not identify sarcastic and insincere exchanges. We found that basic social cognition significantly correlated with standard generalized cognitive measures, whereas advanced social cognition did not. Finally, age at onset had significant impact on social cognition, whereas other epilepsy characteristics did not. SIGNIFICANCE: PWEs have deficits in social cognition when measured using a naturalistic video-based task. Advanced social cognition may be an independent cognitive domain in PWEs that is not adequately measured using standard psychometric instruments. Problems with social cognition may arise as a consequence of epilepsy during the periods of robust social development in childhood and adolescence.

Test-retest, retest, and retest: Growth curve models of repeat testing with Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT).

Computerized neuropsychological testing has become an important tool in the identification and management of sports-related concussions; however, the psychometric effect of repeat testing has not been studied extensively beyond test-retest statistics. The current study analyzed data from Division I collegiate athletes who completed Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) baseline assessments at four sequential time points that varied over the course of their athletic careers. Administrations were part of a larger National Institutes of Health (NIH) study. Growth curve modeling showed that the two memory composite scores increased significantly with successive administrations: Change in Verbal Memory was best represented with a quadratic model, while a linear model best fit Visual Memory. Visual Motor Speed and Reaction Time composites showed no significant linear or quadratic growth. The results demonstrate the effect of repeated test administrations for memory composite scores, while speed composites were not significantly impacted by repeat testing. Acceptable test-retest reliability was demonstrated for all four composites as well.

Recovery of episodic memory subprocesses in mild and complicated mild traumatic brain injury at 1 and 12 months post injury.

INTRODUCTION: Episodic memory complaints are commonly reported after traumatic brain injury (TBI). The contributions of specific memory subprocesses (encoding, consolidation, and retrieval), however, are not well understood in mild TBI (mTBI). In the present study, we evaluated subprocesses of episodic memory in patients with mTBI using the item-specific deficit approach (ISDA), which analyzes responses on list learning tasks at an item level. We also conducted exploratory analyses to evaluate the effects of complicated mTBI (comp-mTBI) on memory. METHOD: We compared episodic verbal memory performance in mTBI (n = 92) at approximately 1 and 12 months post TBI, as well as in a healthy comparison (HC) group (n = 40) at equivalent time points. Episodic memory was assessed using the California Verbal Learning Test-2nd Edition (CVLT-II), and both standard CVLT-II scores and ISDA indices were evaluated. RESULTS: Compared to the HC group, the mTBI group showed significantly poorer encoding and learning across time, as measured by ISDA and CVLT-II. Further analyses of these mTBI subgroups [(noncomplicated mTBI (NC-mTBI, n = 77) and comp-mTBI (n = 15)], indicated that it was the comp-mTBI group who continued to demonstrate poorer encoding ability than the HC group. When the patient groups were directly compared, the NC-mTBI group improved slightly on the ISDA Encoding Deficit Index. While the comp-mTBI group worsened slightly over time, their poorer encoding ability was not likely clinically meaningful. CONCLUSIONS: These findings indicate that, while the NC-mTBI and HC groups' performances were comparable by 12 months, a primary, long-term deficit in encoding of auditory verbal information remained problematic in the comp-mTBI group.