David M Schnyer

University of Texas at Austin | UT · Department of Psychology

Many patients with mild traumatic brain injury (mTBI) are at risk for mental health problems such as posttraumatic stress disorder (PTSD). The objective of this study was to determine whether the polygenic risk for PTSD (or for related mental health disorders or traits including major depressive disorder [MDD] and neuroticism [NEU]) was associated...

Priming refers to the faciliatory processing effects of repeating a stimulus or a task. This ubiquitous phenomenon interest’s memory researchers because its encoding and retrieval dynamics are both similar and different than many other forms of learning examined in this volume. This chapter explores one specific domain of priming that has been exte...

Background The prognostic value of glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) as day-of-injury predictors of functional outcome after traumatic brain injury is not well understood. GFAP is a protein found in glial cells and UCH-L1 is found in neurons, and these biomarkers have been cleared to aid in decisi...

Objective To identify the differences between circadian rhythm (CR) metrics characterized by different mobile sensors and computational methods. Methods We used smartphone tracking and daily survey data from 225 college student participants, applied four methods (survey construct automation, cosinor regression, non-parametric method, Fourier analy...

Importance: Mild traumatic brain injury (mTBI) may impair the ability to work. Strategies to facilitate return to work are understudied. Objective: To assess employment and economic outcomes for employed, working-age adults with mTBI in the 12 months after injury and the association between return to work and employer assistance. Design, settin...

In this article we propose and validate an unsupervised probabilistic model, Gaussian Latent Dirichlet Allocation (GLDA), for the problem of discrete state discovery from repeated, multivariate psychophysiological samples collected from multiple, inherently distinct, individuals. Psychology and medical research heavily involves measuring potentiall...

Cognitive control (CC) is a set of processes that organize, plan, and inhibit actions through mental operations congruent with internal goals. Previous Meta-analysis (Niendam et al., 2012) supports the existence of a superordinate cognitive control network (CCN) comprised of the dorsal lateral prefrontal cortex (DLPFC), anterior cingulate cortex (A...

Several proteins have proven useful as blood-based biomarkers to assist in evaluation and management of traumatic brain injury (TBI). The objective of this study was to determine whether two day-of-injury blood-based biomarkers are predictive of posttraumatic stress disorder (PTSD). We used data from 1143 individuals with mild TBI (mTBI; defined as...

Background After severe traumatic brain injury (sTBI), physicians use long-term prognostication to guide acute clinical care yet struggle to predict outcomes in comatose patients. Purpose To develop and evaluate a prognostic model combining deep learning of head CT scans and clinical information to predict long-term outcomes after sTBI. Materials a...

Major Depressive Disorder (MDD) is a leading cause of disability worldwide and affects up to twenty percent of children and adolescents. Having a mother with Major Depressive Disorder is one of the strongest predictors of depression in late adolescence and early adulthood. Neuroimaging studies consistently report MDD associated dysfunction within t...

The Indoor Air Quality (Indoor Air Quality (IAQ)) of the bedroom environment has recently garnered attention since air pollution can affect sleep. Previous studies investigated IAQ and sleep quality in controlled environments which impacts both self-reported and measured sleep quality. Studies within a participant’s home environment are ecologicall...

Importance: Insomnia is common after traumatic brain injury (TBI) and contributes to morbidity and long-term sequelae. Objective: To identify unique trajectories of insomnia in the 12 months after TBI. Design, setting, and participants: In this prospective cohort study, latent class mixed models (LCMMs) were used to model insomnia trajectories...

Importance Posttraumatic epilepsy (PTE) is a recognized sequela of traumatic brain injury (TBI), but the long-term outcomes associated with PTE independent of injury severity are not precisely known. Objective To determine the incidence, risk factors, and association with functional outcomes and self-reported somatic, cognitive, and psychological...

With the outbreak of the COVID-19 pandemic in 2020, most colleges and universities move to restrict campus activities, reduce indoor gatherings and move instruction online. These changes required that students adapt and alter their daily routines accordingly. To investigate patterns associated with these behavioral changes, we collected smartphone...

Individuals with remitted depression are at greater risk for subsequent depression and therefore may provide a unique opportunity to understand the neurophysiological correlates underlying the risk of depression. Research has identified abnormal resting-state electroencephalography (EEG) power metrics and functional connectivity patterns associated...

Research on the biological basis of reinforcement-learning has focused on how brain regions track expected value based on average reward. However, recent work suggests that humans are more attuned to reward frequency. Furthermore, older adults are less likely to use expected values to guide choice than younger adults. This raises the question of wh...

Objective: Attention bias modification training (ABMT) is purported to reduce depression by targeting and modifying an attentional bias for sadness-related stimuli. However, few tests of this hypothesis have been completed. Method: The present study examined whether change in attentional bias mediated a previously reported association between AB...

Attention bias modification training (ABMT) is purported to reduce depression by targeting and modifying an attentional bias for sadness-related stimuli. However, few tests of this hypothesis have been completed. Method: The current study examined whether change in attentional bias mediated a previously reported association between ABMT condition (...

Background Traumatic brainstem injury has yet to be incorporated into widely used imaging classification systems for traumatic brain injury (TBI), and questions remain regarding prognostic implications for this TBI subgroup. To address this, retrospective data on patients from the multicenter prospective Transforming Research and Clinical Knowledge...

Importance: A head computed tomography (CT) with positive results for acute intracranial hemorrhage is the gold-standard diagnostic biomarker for acute traumatic brain injury (TBI). In moderate to severe TBI (Glasgow Coma Scale [GCS] scores 3-12), some CT features have been shown to be associated with outcomes. In mild TBI (mTBI; GCS scores 13-15)...

UNSTRUCTURED With the outbreak of the COVID-19 pandemic in 2020, most colleges and universities move to restrict campus activities, reduce indoor gatherings and move instruction online. These changes required that students adapt and alter their daily routines accordingly. To investigate patterns associated with these behavioral changes, we collecte...

Circadian rhythm is the natural biological cycle manifested in human daily routines. A regular and stable rhythm is found to be correlated with good physical and mental health. With the wide adoption of mobile and wearable technology, many types of sensor data, such as GPS and actigraphy, provide evidence for researchers to objectively quantify the...

Importance: Moderate to severe traumatic brain injury (msTBI) is a major cause of death and disability in the US and worldwide. Few studies have enabled prospective, longitudinal outcome data collection from the acute to chronic phases of recovery after msTBI. Objective: To prospectively assess outcomes in major areas of life function at 2 weeks...

Background As mobile technologies become ever more sensor-rich, portable, and ubiquitous, data captured by smart devices are lending rich insights into users’ daily lives with unprecedented comprehensiveness and ecological validity. A number of human-subject studies have been conducted to examine the use of mobile sensing to uncover individual beha...

Importance Knowledge of differences in mild traumatic brain injury (mTBI) recovery by sex and age may inform individualized treatment of these patients. Objective To identify sex-related differences in symptom recovery from mTBI; secondarily, to explore age differences within women, who demonstrate poorer outcomes after TBI. Design, Setting, and...

Importance Heterogeneity across patients with traumatic brain injury (TBI) presents challenges for clinical care and intervention design. Identifying distinct clinical phenotypes of TBI soon after injury may inform patient selection for precision medicine clinical trials. Objective To investigate whether distinct neurobehavioral phenotypes can be...

Background This study examined the efficacy of attention bias modification training (ABMT) for the treatment of depression. Methods In this randomized clinical trial, 145 adults (77% female, 62% white) with at least moderate depression severity [i.e. self-reported Quick Inventory of Depressive Symptomatology (QIDS-SR) ⩾13] and a negative attention...

Objective Prompt, accurate, objective assessment of concussion is crucial as delays can lead to increased short and long-term consequences. The purpose of this study was to derive an objective multimodal concussion index (CI) using EEG at its core, to identify concussion, and to assess change over time throughout recovery. Methods Male and female...

Importance: An objective, reliable indicator of the presence and severity of concussive brain injury and of the readiness for the return to activity has the potential to reduce concussion-related disability. Objective: To validate the classification accuracy of a previously derived, machine learning, multimodal, brain electrical activity-based C...

Loneliness is a widely affecting mental health symptom and can be mediated by and co-vary with patterns of social exposure. Using momentary survey and smartphone sensing data collected from 129 Android-using college student participants over three weeks, we (1) investigate and uncover the relations between momentary loneliness experience and compan...

While depression is a leading cause of disability, prior investigations of depression have been limited by studying correlates in isolation. A data-driven approach was applied to identify out-of-sample predictors of current depression from adults (N = 217) sampled on a continuum of no depression to clinical levels. The current study used elastic ne...

Introduction Return to work (RTW) is an important milestone of mild traumatic brain injury (mTBI) recovery. The objective of this study was to evaluate whether baseline clinical variables, three-month RTW, and three-month postconcussional symptoms (PCS) were associated with six-month RTW after mTBI. Methods Adult subjects from the prospective mult...

Study Objectives The purpose of this study was to examine how rest-activity (RA) rhythm stability may be associated with white matter microstructure across the lifespan in healthy adults free of significant cardiovascular risk. Methods We analyzed multi-shell diffusion tensor images from 103 healthy young and older adults using tract-based spatial...

Research on the biological basis of reinforcement-learning has focused on how brain regions track expected value based on average reward. However, recent work suggests that humans are more attuned to reward frequency. Furthermore, older adults are less likely to use expected values to guide choice than younger adults. This raises the question of wh...

Research on the biological basis of reinforcement-learning has focused on how brain regions track expected value based on average reward. However, recent work suggests that humans are more attuned to reward frequency. Furthermore, older adults are less likely to use expected values to guide choice than younger adults. This raises the question of wh...

Loneliness is a widely affecting mental health symptom and can be mediated by and co-vary with patterns of social exposure. Using momentary survey and smartphone sensing data collected from 129 Android-using college student participants over three weeks, we (1) investigate and uncover the relations between momentary loneliness experience and compan...

As mobile technologies become ever more sensor-rich, portable, and ubiquitous, data captured by smart devices are lending rich insights into users' daily lives with unprecedented comprehensiveness, unobtrusiveness, and ecological validity. A number of human-subject studies have been conducted in the past decade to examine the use of mobile sensing...

While major depressive disorder has been associated with increased veridical memory for negative information, prior false memory literature has linked high depressive symptoms to increased false memory for negative information. We tested whether these contradictory findings may be due to semantic and emotional cohesion inflating false alarm rates i...

Background: This study examined the efficacy Attention Bias Modification Training (ABMT) for the treatment of depression. Methods: In this randomized clinical trial, 145 adults (77% female, 62% white) with at least moderate depression severity (i.e., self-reported Quick Inventory of Depressive Symptomatology (QIDS-SR) ≥ 13) and a negative attention...

The present research investigated whether the differential recognition thresholds associated with memory for self-relevant negative feedback stem from processes occurring at encoding and/or suppression at retrieval. Socioemotional and monetary incentives offered before and after encoding did not significantly affect recognition thresholds for negat...

Background Individual differences in reward‐related processes, such as reward responsivity and approach motivation, appear to play a role in the nature and course of depression. Prior work suggests that cognitive biases for valenced information may contribute to these reward processes. Yet there is little work examining how biased attention, proces...

Polytrauma and traumatic brain injury (TBI) frequently co-occur and outcomes are routinely measured by the Glasgow Outcome Scale-Extended (GOSE). Polytrauma may confound GOSE measurement of TBI-specific outcomes. Adult patients with TBI from the prospective Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilo...

Highlights: Rest-activity rhythm stability was associated with greater white matter integrity in healthy young and older adults free of confounding health risk factors. Associated regions included the corpus callosum, anterior corona radiata, and superior longitudinal fasciculus.This relationship appears to be stable throughout the lifespan. Older...

This study aimed to elucidate the structure of the Rivermead Postconcussion Symptoms Questionnaire (RPQ) and evaluate its longitudinal and group variance. Factor structures were developed and compared in 1,011 patients with mild traumatic brain injury (mTBI; i.e., Glasgow Coma Scale score 13-15) from the Transforming Research and Clinical Knowledge...

Substance use is commonly associated with traumatic brain injury (TBI). We investigate associations between active substance use, peri-injury factors, and outcome after TBI across three U.S. Level I trauma centers. TBI subjects from the prospective Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) with M...

In this chapter, we explore Support Vector Machine (SVM)-a machine learning method that has become exceedingly popular for neuroimaging analysis in recent years. Because of their relative simplicity and flexibility for addressing a range of classification problems, SVMs distinctively afford balanced predictive performance, even in studies where sam...

Individual differences in reward-related processes, such as reward responsivity and approach motivation, appear to play a role in the nature and course of depression. Prior work has suggested that an important aspect of these reward processes may be cognitive biases for valenced information. Yet there is little work examining how biased attention,...

INTRODUCTION Brain-derived neurotrophic factor (BDNF) is a common neurotrophin important to neuronal survival and plasticity. We aim to elucidate the associations between the BDNF single nucleotide polymorphism (SNP) Val66Met (rs6265) and 3-mo outcome after traumatic brain injury (TBI). METHODS TBI subjects from the prospective, multicenter Transf...

Background: After traumatic brain injury (TBI), plasma concentration of glial fibrillary acidic protein (GFAP) correlates with intracranial injury visible on CT scan. Some patients with suspected TBI with normal CT findings show pathology on MRI. We assessed the discriminative ability of GFAP to identify MRI abnormalities in patients with normal C...

Brooding, which refers to a repetitive focus on one's distress, is associated with functional connectivity within Default-Mode, Salience, and Executive-Control networks (DMN; SN; ECN), comprising the so-called "triple-network" of attention. Individual differences in brain structure that might perseverate dysfunctional connectivity of brain networks...

The purpose of the present study was to evaluate the impact of sleep disturbances on subsequent depressive symptomatology among a representative sample of patients following traumatic brain injury (TBI). Within a retrospective cohort design, our sample included 305 individuals from the Transforming Research and Clinical Knowledge in Traumatic Brain...

Older adults had widespread decreased functional connectivity at a whole brain level, and decreased functional connectivity within default mode and frontoparietal networks. Older adults also showed lower global efficiency at a whole brain level compared to young adults. Within the frontoparietal network, older adults had greater efficiency. Great...

Importance Most traumatic brain injuries (TBIs) are classified as mild (mTBI) based on admission Glasgow Coma Scale (GCS) scores of 13 to 15. The prevalence of persistent functional limitations for these patients is unclear. Objectives To characterize the natural history of recovery of daily function following mTBI vs peripheral orthopedic traumat...

Introduction: Over 70% of traumatic brain injuries (TBI) are classified as mild (mTBI), which present heterogeneously. Associations between pre-injury comorbidities and outcomes are not well-understood, and understanding their status as risk factors may improve mTBI management and prognostication. Methods: mTBI subjects (GCS 13–15) from TRACK-TBI...

In an increasingly complex and fast-paced world, organizations must develop strategies to enhance or optimize worker performance in order to achieve their goals. This is especially true, for example, in the military, where highly skilled and competent personnel are needed, and where, because of lengthy training requirements and financial constraint...

This chapter summarizes and integrates the various approaches to optimizing human performance addressed in this book. Strategies for performance enhancement are evaluated across the three main domains of focus in this volume—physical, cognitive, and social. Moreover, for each domain, the authors offer suggestions for those that may be applied in th...

The stereotype linking Blacks with threat is assumed to underlie neurocognitive processing differences between Black and White faces. However, research showing that racial biases are context-dependent suggests that context may interact with threat stereotypes in such a way as to alter when a person is seen as threatening. The present research teste...

Importance Traumatic brain injury (TBI) has been associated with adverse mental health outcomes, such as posttraumatic stress disorder (PTSD) and major depressive disorder (MDD), but little is known about factors that modify risk for these psychiatric sequelae, particularly in the civilian sector. Objective To ascertain prevalence of and risk fact...

Sleep-activity cycles are cued by circadian rhythms, which are endogenously generated patterns that control cyclical physiological processes. Circadian rhythms change throughout the lifespan and may account for changes older adults commonly experience in sleep behavior, such as increased morningness preference, greater sleep fragmentation, delayed...

Categorizing and individual as a racial ingroup or outgroup member results in processing and memory differences. However, despite processing differences for racial ingroups and outgroups, very little is known about processing of racial ingroup and outgroup members during intergroup contexts. Thus, the present research investigated attention and mem...

Theoretical models and empirical research point to negatively biased attention as a maintaining factor in depression. Although preliminary studies suggest experimentally modifying attentional biases (i.e., attentional bias modification; ABM) reduces depression symptoms and depression risk, relatively few rigorous studies with clinical samples have...

Introduction: Mild traumatic brain injury (MTBI) can cause persistent functional deficits and healthcare burden. Understanding the association between intracranial contusions and outcome may aid in MTBI treatment and prognosis. Methods: MTBI patients with Glasgow Coma Scale 13–15 and 6-month outcomes [Glasgow Outcome Scale-Extended (GOSE)], without...

Theoretical models and empirical research point to negatively biased attention as a maintaining factor in depression. Although preliminary studies suggest experimentally modifying attentional biases (i.e., attentional bias modification; ABM) reduces depression symptoms and depression risk, relatively few rigorous studies with clinical samples have...

Functional brain networks including Default Mode, Salience, and Executive Control (DMN; SN; ECN), collectively called the 'triple-network', are associated with Depressive Rumination (DR) severity in Major Depressive Disorder (MDD). The underlying white-matter (WM) microstructure supporting these networks and its precise role in DR remains unknown,...

Context: Without a true criterion standard assessment, the sport-related concussion (SRC) diagnosis remains subjective. Inertial balance sensors have been proposed to improve acute SRC assessment, but few researchers have studied their clinical utility. Objective: To determine if group differences exist when using objective measures of balance i...

A rapidly expanding scientific literature supports the frequent co-occurrence of sleep and circadian disturbances following mild traumatic brain injury (mTBI). Although many questions remain unanswered, the preponderance of evidence suggests that sleep and circadian disorders can result from mTBI. Among those with mTBI, sleep disturbances and clini...

Importance Mild traumatic brain injury (mTBI) affects millions of Americans each year. Lack of consistent clinical practice raises concern that many patients with mTBI may not receive adequate follow-up care. Objective To characterize the provision of follow-up care to patients with mTBI during the first 3 months after injury. Design, Setting, an...

This chapter illustrates a convergent approach to memory research highlighting both lateral convergence (the testing of theory convergence across different methodologies and dependent variables) and vertical convergence (the testing of theory convergence at different levels of data aggregation/analysis). The need for the latter is illustrated by co...

A concerted e ort to tackle the global health problem posed by traumatic brain injury (TBI) is long overdue. TBI is a public health challenge of vast, but insu ciently recognised, proportions. Worldwide, more than 50 million people have a TBI each year, and it is estimated that about half the world’s population will have one or more TBIs over their...