Publications by authors named "Taru Flagan"

Objective: Microtubule-associated protein tau (MAPT) mutations cause frontotemporal lobar degeneration, and novel biomarkers are urgently needed for early disease detection. We used task-free functional magnetic resonance imaging (fMRI) mapping, a promising biomarker, to analyze network connectivity in symptomatic and presymptomatic MAPT mutation carriers.

Methods: We compared cross-sectional fMRI data between 17 symptomatic and 39 presymptomatic carriers and 81 controls with (1) seed-based analyses to examine connectivity within networks associated with the 4 most common MAPT-associated clinical syndromes (ie, salience, corticobasal syndrome, progressive supranuclear palsy syndrome, and default mode networks) and (2) whole-brain connectivity analyses.

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Article Synopsis
  • - The study investigates whether presymptomatic carriers of MAPT mutations, associated with frontotemporal dementia, exhibit lower brain volumes prior to showing symptoms, using a voxelwise analysis approach on brain images.
  • - The research included 22 symptomatic carriers and 43 presymptomatic carriers, revealing that symptomatic carriers exhibited significant gray and white matter atrophy in specific brain regions, while about 20% of presymptomatic carriers showed reduced gray matter in critical areas as early as their thirties.
  • - Findings suggest that some presymptomatic carriers are already experiencing early neurodegeneration in the mesial temporal lobe, with a trend indicating that this risk increases as they age.
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Mutations in progranulin (GRN) cause heterogeneous clinical syndromes, including behavioral variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA), corticobasal syndrome (CBS) and Alzheimer-type dementia (AD-type dementia). Human studies have shown that presymptomatic GRN carriers feature reduced connectivity in the salience network, a system targeted in bvFTD. Mice with homozygous deletion of GRN, in contrast, show thalamo-cortical hypersynchrony due to aberrant pruning of inhibitory synapses onto thalamo-cortical projection neurons.

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We cannot see the minds of others, yet people often spontaneously interpret how they are viewed by other people (i.e., meta-perceptions) and often in a self-flattering manner.

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The PASTOR framework needs to be reconciled with existing research on positive illusions, which finds that positive appraisals of stressors have a short shelf life as a mechanism of resilience, do not draw on costly executive functioning, and rely on neural networks that are distinct from those found in studies of experimentally instructed reappraisal or value.

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Posttraumatic stress disorder (PTSD) has been linked to deficits in response inhibition, and neuroimaging research suggests this may be due to differences in prefrontal cortex recruitment. The current study examined relationships between PTSD from intimate partner violence (IPV) and neural responses during inhibition. There were 10 women with PTSD from IPV and 12 female control subjects without trauma history who completed the stop signal task during functional magnetic resonance imaging.

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Objective: Approximately 10% of young adults report non-medical use of stimulants (cocaine, amphetamine, methylphenidate), which puts them at risk for the development of dependence. This fMRI study investigates whether subjects at early stages of stimulant use show altered decision making processing.

Methods: 158 occasional stimulants users (OSU) and 50 comparison subjects (CS) performed a "risky gains" decision making task during which they could select safe options (cash in 20 cents) or gamble them for double or nothing in two consecutive gambles (win or lose 40 or 80 cents, "risky decisions").

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Background: Although evidence exists for abnormal brain function across various anxiety disorders, direct comparison of neural function across diagnoses is needed to elicit abnormalities common across disorders and those distinct to a particular diagnosis.

Aims: To delineate common and distinct abnormalities within generalised anxiety (GAD), panic and social anxiety disorder (SAD) during affective processing.

Method: Fifty-nine adults (15 with GAD, 15 with panic disorder, 14 with SAD, and 15 healthy controls) underwent functional magnetic resonance imaging while completing a facial emotion matching task with fearful, angry and happy faces.

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Background: The neural processes underlying the benefits of cognitive behavioral treatment (CBT) for generalized anxiety disorder (GAD) are not well understood.

Methods: Twenty-one (n=21) adults with a principal diagnosis of GAD and eleven (n=11) non-anxious healthy controls (HC) underwent functional magnetic resonance imaging while completing a facial emotion processing task. Responses to threat-related emotionality (i.

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An integration of existing research and newly conducted psychophysiological interaction (PPI) connectivity analyses suggest a new framework for understanding the contribution of midline regions to social cognition. Recent meta-analyses suggest that there are no midline regions that are exclusively associated with self-processing. Whereas medial prefrontal cortex (MPFC) is broadly modulated by self-processing, subdivisions within MPFC are differentially modulated by the evaluation of close others (ventral MPFC: BA 10/32) and the evaluation of other social targets (dorsal MPFC: BA 9/32).

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Computerized attention modification is a relatively new and empirically validated treatment approach for different types of anxiety disorders. However, its neural basis and processes involved are poorly understood. This study examined the effect of a one-time application of an attention modification program (AMP) on neural substrates underlying emotion processing in individuals with high social anxiety.

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Therapy for combat and accident-related posttraumatic stress disorder (PTSD) has been reported to influence amygdala and anterior cingulate cortex (ACC) response during emotional processing. It is not yet understood how therapy influences different phases of emotional processing, and whether previous findings generalize to other PTSD populations. We hypothesized that cognitive trauma therapy for battered women (CTT-BW) would alter insula, amygdala, and cingulate responses during anticipation and presentation of emotional images.

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Liberals and conservatives exhibit different cognitive styles and converging lines of evidence suggest that biology influences differences in their political attitudes and beliefs. In particular, a recent study of young adults suggests that liberals and conservatives have significantly different brain structure, with liberals showing increased gray matter volume in the anterior cingulate cortex, and conservatives showing increased gray matter volume in the in the amygdala. Here, we explore differences in brain function in liberals and conservatives by matching publicly-available voter records to 82 subjects who performed a risk-taking task during functional imaging.

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Understanding the neural processes that characterize elite performers is a first step to develop a neuroscience model that can be used to improve performance in stressful circumstances. Adventure racers are elite athletes that operate in small teams in the context of environmental and physical extremes. In particular, awareness of team member's emotional status is critical to the team's ability to navigate high-magnitude stressors.

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Childhood maltreatment (CM) is a strong risk factor for development of posttraumatic stress disorder (PTSD) upon adult exposure to extreme adverse events. However, the neural underpinnings of this relationship are not well understood. Here, we test the hypothesis that severity of CM history is positively correlated with emotion-processing limbic and prefrontal brain activation/connectivity and negatively correlated with prefrontal gray matter volumes in women with PTSD due to intimate-partner violence (IPV-PTSD).

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Background: While stimulant-dependent individuals continue to make risky decisions, in spite of poor outcomes, much less is known about decision-making characteristics of occasional stimulant users (OSU) at risk for developing stimulant dependence. This study examines whether OSU exhibit inefficient learning and execution of reinforced decision-outcome contingencies.

Methods: Occasional stimulant users (n = 161) and stimulant-naïve comparison subjects (CTL) (n = 48) performed a Paper Scissors Rock task during functional magnetic resonance imaging.

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Background: Exposure to psychological stress during combat can lead to posttraumatic stress disorder (PTSD). Anticipation of aversive events is often associated with an intense emotional state in individuals with PTSD. Both the valence (i.

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Individuals are willing to sacrifice their own resources to promote equality in groups. These costly choices promote equality and are associated with behavior that supports cooperation in humans, but little is known about the brain processes involved. We use functional MRI to study egalitarian preferences based on behavior observed in the "random income game.

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Context: Posttraumatic stress disorder (PTSD) has been associated with executive or attentional dysfunction and problems in emotion processing. However, it is unclear whether these two domains of dysfunction are related to common or distinct neurophysiological substrates.

Objective: To examine the hypothesis that greater neuropsychological impairment in PTSD relates to greater disruption in prefrontal-subcortical networks during emotional anticipation.

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Article Synopsis
  • Pregabalin shows potential in treating anxiety disorders by influencing brain activation during emotional processing, similar to SSRIs and benzodiazepines.
  • A recent study using fMRI found that pregabalin reduced activation in the amygdala and insula during fearful and angry face-matching tasks, but interestingly, a lower dose (50 mg) had stronger effects than a higher dose (200 mg).
  • These findings suggest that pregabalin may have distinct neural effects that contribute to its unique role in anxiety treatment, particularly in how the brain processes emotional stimuli.
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Background: It is unclear whether and how elite athletes process physiological or psychological challenges differently than healthy comparison subjects. In general, individuals optimize exercise level as it relates to differences between expected and experienced exertion, which can be conceptualized as a body prediction error. The process of computing a body prediction error involves the insular cortex, which is important for interoception, i.

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Sensation seeking has been linked to increased risk taking and is therefore crucial in influencing behavioral outcomes of risk-taking behavior. Using functional magnetic resonance imaging (fMRI), the neural underpinnings of risk appraisal were studied in a large subject sample (n=188), stratified according to thrill and adventure seeking (TAS) ratings. As defined by a median split of the sample, low and high TAS groups were compared on a simple decision-making task completed during fMRI.

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Individuals with high anxiety show heightened neural activation in affective processing regions, including the amygdala and insula. Activations have been shown to be correlated with anxiety severity, but although anxiety is a heterogeneous state, prior studies have not systematically disentangled whether neural activity in affective processing circuitry is uniquely related to specific domains of anxiety. Forty-five young adults were tested on an emotional face processing task during functional magnetic resonance imaging.

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Several studies provide empirical evidence for the association between impulsivity and time perception. However, little is known about the neural substrates underlying this function. This investigation examined the influence of impulsivity on neural activation patterns during the encoding and reproduction of intervals with durations of 3, 9 and 18s using event-related functional magnetic resonance imaging (fMRI).

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Article Synopsis
  • Pregabalin (PGB) shows promise as a treatment for generalized and social anxiety disorders by acting on calcium channels and enhancing GABA activity, which helps reduce neurotransmitter release.
  • A study with 16 healthy participants used fMRI to explore how PGB affects brain activation during emotional anticipation of images, comparing effects of placebo, 50 mg, and 200 mg doses.
  • Results indicated PGB decreased activation in the left amygdala and anterior insula while increasing anterior cingulate activation, suggesting that its anxiolytic effects may involve common brain mechanisms across different anxiety medications.
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