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Biology subjects

Schultz, D. H.

Publications and source records attributed to Schultz, D. H..

9 recordsLinked to original sources

Cognitive reappraisal of food and emotion cues involves common and unique neural contributions

Obesity is a growing public health concern with more than 40% of adults meeting criteria for obesity in the United States. Although many treatments seek to lower individuals weight, few treatments have focused on cognitive strategies to change the way individuals think about food, therefore, decreasing consumption of non-nutrient-dense foods. Cognitive reappraisal is one strategy that involves changing the way one thinks about a situation and can be used to downregulate responses to those stimuli. Leveraging this intuitive, cost-effective strategy to decrease ones desire to eat unhealthy food and therefore, decrease overeating, could improve physical and mental health. The present study identified brain regions that are differentially activated when using cognitive reappraisal to downregulate responses to food (FR) versus when using the same strategy to downregulate negative emotions (ER). We collected functional magnetic resonance imaging (fMRI) data in 63 undergraduate students while participants completed both tasks. There was increased reappraisal-related activation in widespread regions across both tasks, including in expected subcortical (i.e., striatum) and cortical areas (i.e., visual, frontoparietal). We also found domain-specific activity, with greater insula activation in the FR than the ER task and greater hippocampal activation in the ER than the FR task. These results reveal domain-general and domain-specific effects of cognitive reappraisal in FR and ER tasks that inform future work examining eating behavior. Taken together, a better explication of the overlapping and discrete processes of food regulation, as it compares to other applications of this regulatory strategy can inform new intervention targets.

neuroscience↗

Second language learning in older adults modulates Stroop task performance and brain activation

Numerous studies have highlighted cognitive benefits in lifelong bilinguals during aging, manifesting as superior performance on cognitive tasks compared to monolingual counterparts. Yet, the cognitive impacts of acquiring a new language in older adulthood remain unexplored. In this study, we assessed both behavioral and fMRI responses during a Stroop task in older adults, pre- and post language-learning intervention. A group of 41 participants (age:60-80) from a predominantly monolingual environment underwent a four-month online language course, selecting a new language of their preference. This intervention mandated engagement for 90 minutes a day, five days a week. Daily tracking was employed to monitor progress and retention. All participants completed a color-word Stroop task inside the scanner before and after the language instruction period. We found that performance on the Stroop task, as evidenced by accuracy and reaction time, improved following the language learning intervention. With the neuroimaging data, we observed significant differences in activity between congruent and incongruent trials in key regions in the prefrontal and parietal cortex. These results are consistent with previous reports using the Stroop paradigm. We also found that the amount of time participants spent with the language learning program was related to differential activity in these brain areas. Specifically, we found that people who spent more time with the language learning program showed a greater increase in differential activity between congruent and incongruent trials after the intervention relative to before. Future research is needed to determine the optimal parameters for language learning as an effective cognitive intervention for aging populations. We propose that with sufficient engagement, language learning can enhance specific domains of cognition such as the executive functions. These results extend the understanding of cognitive reserve and its augmentation through targeted interventions, setting a foundation for future investigations.

neuroscience↗

Is it sandbagging or is it just apathy? Baseline ImPACT and external validity indicators in collegiate athletes

ObjectiveBaseline cognitive testing is important for sport concussion management. Assessing baseline data for both the validity and reliability is vital to ensuring its utility. Stand-alone performance validity tests (PVT) and embedded validity indicators (EVI) (collectively called "validity measures" hereafter) are commonly used in neuropsychological testing and screening. This study further investigates efficient ways to assess validity of baseline cognitive testing. Methods231 NCAA athletes completed baseline assessment with ImPACT and one of two PVTs: Medical Symptom Validity Test or Rey Dot Counting Test. The relationship between scores on validity measures and cognitive performance, symptoms, and sleep was assessed. ResultsAthletes who failed two or more validity measures performed worse on the Visual Motor Speed Composite while athletes failing three or more measures performed worse on the Reaction Time Composite. Those athletes who failed validity measures and also reported poor sleep performed worse on both composites. Self-reported symptoms and hours of sleep were not independently associated with failing validity measures. Lastly, athletes with self-reported ADHD and/or LD were more likely to fail two+ validity measures (46% versus 27% of neurotypical athletes). ConclusionsConsistent with previous research, ImPACT Baseline++ only identified 1.7% of the samples data as invalid despite 4.8% of the dataset failing a combination of PVT and EVI and an additional 42.9% failing at least EVI alone. Results suggest that assessing validity on a continuum and using multiple validity measures may be useful to identify data validity that falls in the middle of the continuum. Public Significance StatementBaseline concussion testing is common and often mandated prior to sport participation, however, a baseline only has utility if it is both a reliable and valid representation of the athletes healthy and optimal functioning. This study adds to the growing body of literature demonstrating that baseline testing may frequently have questionable validity. It also provides support to the value of conceptualizing validity as a spectrum, rather than dichotomy and is the first to apply the concept to baseline concussion testing data.

animal behavior and cognition↗

Concussion-related disruptions to hub connectivity in the default mode network are related to symptoms and cognition

Concussions present with a myriad of symptomatic and cognitive concerns; however, the relationship between these functional disruptions and the underlying changes in the brain are not yet well understood. Hubs, or brain regions that are connected to many different functional networks, may be specifically disrupted after concussion. Given the implications in concussion research, we quantified hub disruption within the default mode network (DMN) and between the DMN and other brain networks. We collected resting-state functional magnetic resonance imaging data from collegiate student-athletes (n = 44) at three timepoints: baseline (prior to beginning their athletic season), acute post-injury (approximately 48 hours after a diagnosed concussion), and recovery (after starting return-to-play progression, but prior to returning to contact). We used self-reported symptoms and computerized cognitive assessments collected across similar timepoints to link these functional connectivity changes to clinical outcomes. Concussion resulted in increased connectivity between regions within the DMN compared to baseline and recovery, and this post-injury connectivity was more positively related to symptoms and more negatively related to visual memory performance compared to baseline and recovery. Further, concussion led to decreased connectivity between DMN hubs and visual network non-hubs relative to baseline and recovery, and this post-injury connectivity was more negatively related to somatic symptoms and more positively related to visual memory performance compared to baseline and recovery. Relationships between functional connectivity, symptoms, and cognition were not significantly different at baseline versus recovery. These results highlight a unique relationship between self-reported symptoms, visual memory performance and acute functional connectivity changes involving DMN hubs after concussion in athletes. This may provide evidence for a disrupted balance of within- and between-network communication highlighting possible network inefficiencies after concussion. These results aid in our understanding of the pathophysiological disruptions after concussion and inform our understanding of the associations between disruptions in brain connectivity and specific clinical presentations acutely post-injury.

neuroscience↗

The human brain's intrinsic network architecture is organized to represent diverse cognitive task information

A set of distributed cognitive control networks are known to contribute to diverse cognitive demands, yet it is unclear how these networks gain this domain-general capacity. We hypothesized that this capacity is largely due to the particular organization of the human brains intrinsic network architecture. Specifically, we tested the possibility that each brain regions domain generality is reflected in its level of global (hub-like) intrinsic connectivity, as well as its particular global connectivity pattern (connectivity fingerprint). Consistent with prior work, we found that cognitive control networks exhibited domain generality, as they represented diverse task context information covering sensory, motor response, and logic rule domains. Supporting our hypothesis, we found that the level of global intrinsic connectivity (estimated with resting-state fMRI) was correlated with domain generality during tasks. Further, using a novel information fingerprint mapping approach, we found that each cognitive control regions unique rule response profile (information fingerprint) could be predicted based on its unique intrinsic connectivity fingerprint and the information content in non-cognitive control regions. Together these results suggest that the human brains intrinsic network architecture supports its ability to represent diverse cognitive task information, largely via the location of multiple-demand regions within the brains global network organization.

neuroscience↗

Constructing neural network models from brain data reveals representational transformations underlying adaptive behavior

The human ability to adaptively implement a wide variety of tasks is thought to emerge from the dynamic transformation of cognitive information. We hypothesized that these transformations are implemented via conjunctive activations in conjunction hubs - brain regions that selectively integrate sensory, cognitive, and motor activations. We used recent advances in using functional connectivity to map the flow of activity between brain regions to construct a task-performing neural network model from fMRI data during a cognitive control task. We verified the importance of conjunction hubs in cognitive computations by simulating neural activity flow over this empirically-estimated functional connectivity model. These empirically-specified simulations produced above-chance task performance (motor responses) by integrating sensory and task rule activations in conjunction hubs. These findings reveal the role of conjunction hubs in supporting flexible cognitive computations, while demonstrating the feasibility of using empirically-estimated neural network models to gain insight into cognitive computations in the human brain.

neuroscience↗

Flexible coordinator and switcher hubs for adaptive task control

Functional connectivity studies have identified at least two large-scale neural systems that constitute cognitive control networks - the frontoparietal network (FPN) and cingulo-opercular network (CON). Control networks are thought to support goal-directed cognition and behavior. It was previously shown that the FPN flexibly shifts its global connectivity pattern according to task goal, consistent with a "flexible hub" mechanism for cognitive control. Our aim was to build on this finding to develop a functional cartography (a multi-metric profile) of control networks in terms of dynamic network properties. We quantified network properties in (male and female) humans using a high-control-demand cognitive paradigm involving switching among 64 task sets. We hypothesized that cognitive control is enacted by the FPN and CON via distinct but complementary roles reflected in network dynamics. Consistent with a flexible "coordinator" mechanism, FPN connections were varied across tasks, while maintaining within-network connectivity to aid cross-region coordination. Consistent with a flexible "switcher" mechanism, CON regions switched to other networks in a task-dependent manner, driven primarily by reduced within-network connections to other CON regions. This pattern of results suggests FPN acts as a dynamic, global coordinator of goal-relevant information, while CON transiently disbands to lend processing resources to other goal-relevant networks. This cartography of network dynamics reveals a dissociation between two prominent cognitive control networks, suggesting complementary mechanisms underlying goal-directed cognition. Significance StatementCognitive control supports a variety of behaviors requiring flexible cognition, such as rapidly switching between tasks. Furthermore, cognitive control is negatively impacted in a variety of mental illnesses. We used tools from network science to characterize the implementation of cognitive control by large-scale brain systems. This revealed that two systems - the frontoparietal (FPN) and cingulo-opercular (CON) networks - have distinct but complementary roles in controlling global network reconfigurations. The FPN exhibited properties of a flexible coordinator (orchestrating task changes), while CON acted as a flexible switcher (switching specific regions to other systems to lend processing resources). These findings reveal an underlying distinction in cognitive processes that may be applicable to clinical, educational, and machine learning work targeting cognitive flexibility.

neuroscience↗

Global connectivity of the frontoparietal cognitive control network is related to depression symptoms in undiagnosed individuals

We all vary in our mental health, even among healthy (undiagnosed) individuals. Understanding this variability may reveal factors driving the onset of mental illness, as well as factors driving sub-clinical mental health problems that can still influence quality of life. To better understand the large-scale brain network mechanisms underlying this variability in mental health we examined the relationship between mental health symptoms and resting-state functional connectivity patterns in cognitive control systems. The frontoparietal cognitive control network (FPN) consists of flexible hubs that can regulate distributed systems depending on current goals, and dysfunction in the FPN has been identified in a variety of psychiatric disorders. Alterations in FPN connectivity may influence mental health by disrupting the ability to regulate symptoms in a goal-directed manner. This suggests that the FPN may play an important role in the promotion and maintenance of mental health generally. Here we test the hypothesis that disruptions in FPN connectivity are related to mental health (depression) symptoms even among healthy individuals. This hypothesis is consistent with a general role of FPN in the regulation of mental health symptoms. We found that depression symptoms were negatively correlated with between-network global connectivity (BGC) of the FPN as well as the default mode network (DMN). This suggests that decreased connectivity between the FPN (and, separately, DMN) and the rest of the brain is related to increased depression symptoms among undiagnosed individuals. These findings complement previous clinical studies to support the hypothesis that global FPN connectivity contributes to the regulation of mental health symptoms across both mentally healthy and unhealthy individuals.

neuroscience↗

Cognitive task information is transferred between brain regions via resting-state network topology

Resting-state network connectivity has been associated with a variety of cognitive abilities, yet it remains unclear how these connectivity properties might contribute to the neurocognitive computations underlying these abilities. We developed a new approach - information transfer mapping - to test the hypothesis that resting-state functional network topology describes the computational mappings between brain regions that carry cognitive task information. Here we report that the transfer of diverse, task-rule information in distributed brain regions can be predicted based on estimated activity flow through resting-state network connections. Further, we find that these task-rule information transfers are coordinated by global hub regions within cognitive control networks. Activity flow over resting-state connections thus provides a large-scale network mechanism for cognitive task information transfer and global information coordination in the human brain, demonstrating the cognitive relevance of resting-state network topology.

neuroscience↗