Publications by authors named "Thomas Van Vleet"

Background: Executive function encompasses a set of higher-order cognitive processes, including planning, cognitive flexibility, and inhibitory control, that are essential for goal-directed behavior. These abilities are adversely affected by age, with executive dysfunction ultimately impairing the performance of activities of daily living.

Objective: This study aimed to assess the validity of a computerized cognitive assessment in predicting executive function performance in healthy older adults.

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Background: Computerized cognitive assessments are most often validated against standard neuropsychological measures with limited validation against biological indices of brain health.

Objective: This study aimed to evaluate whether a self-administered computerized cognitive assessment is associated with cholinergic neurotransmission using the vesicular acetylcholine transporter ligand [18F]fluoroethoxybenzovesamicol (FEOBV) and positron emission tomography (PET).

Methods: In a retrospective analysis, we report baseline data from the Improving Neurological Health in Aging via Neuroplasticity-Based Computerized Exercise (INHANCE) trial.

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Aging is associated with dysfunction in the cholinergic system, including degeneration of basal forebrain cholinergic terminals that innervate the cortex, which directly contributes to age- and disease-related cognitive decline. In this study, we used [18F]fluoroethoxybenzovesamicol ([18F]FEOBV) positron emission tomography (PET) imaging to assess the effect of age on cholinergic terminal integrity in predefined regions of interest and its relationship to cognitive performance in healthy older adults who underwent neuropsychological assessment and FEOBV PET brain imaging. Our results showed age-related reductions in FEOBV binding, particularly in the anterior cingulate cortex-the primary region of interest-as well as in the striatum, posterior cingulate cortex, and primary auditory cortex.

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Aging is associated with dysfunction in the cholinergic system, including degeneration of basal forebrain cholinergic terminals that innervate the cortex, which directly contributes to age- and disease-related cognitive decline. In this study, we used [18F]fluoroethoxybenzovesamicol ([18F]FEOBV) positron emission tomography (PET) imaging to assess the effect of age on cholinergic terminal integrity in predefined regions of interest and its relationship to cognitive performance in healthy older adults who underwent neuropsychological assessment and FEOBV PET brain imaging. Our results showed age-related reductions in FEOBV binding, particularly in the anterior cingulate cortex-our primary region of interest-as well as in the striatum, posterior cingulate cortex, and primary auditory cortex.

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Background: Our current understanding of how computerized brain training drives cognitive and functional benefits remains incomplete. This paper describes the protocol for Improving Neurological Health in Aging via Neuroplasticity-based Computerized Exercise (INHANCE), a randomized controlled trial in healthy older adults designed to evaluate whether brain training improves cholinergic signaling.

Objective: INHANCE evaluates whether 2 computerized training programs alter acetylcholine binding using the vesicular acetylcholine transporter ligand [18F] fluoroethoxybenzovesamicol ([18F] FEOBV) and positron emission tomography (PET).

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Background: Post-acute sequelae of SARS-CoV-2 infection (PASC) symptoms have broad impact, and may affect individuals regardless of COVID-19 severity, socioeconomic status, race, ethnicity, or age. A prominent PASC symptom is cognitive dysfunction, colloquially referred to as "brain fog" and characterized by declines in short-term memory, attention, and concentration. Cognitive dysfunction can severely impair quality of life by impairing daily functional skills and preventing timely return to work.

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Inhibitory control underlies one's ability to maintain goal-directed behavior by inhibiting prepotent responses or ignoring irrelevant information. Recent models suggest that impaired inhibition of negative information may contribute to depressive symptoms, and that this association is mediated by rumination. However, the exact nature of this association, particularly in non-clinical samples, is unclear.

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Objective: We conducted a multisite, randomized, double-blinded, controlled trial to examine the effectiveness of a digital health intervention targeting the intrinsic regulation of goal-directed alertness in patients with chronic hemispatial neglect.

Methods: Forty-nine participants with hemispatial neglect, who demonstrated significant spatially biased attention after acquired brain injury, were randomly assigned to the experimental attention remediation treatment or the active control group. The participants engaged with the remotely administered interventions for 12 weeks.

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Cognitive models of depression suggest that depressed individuals exhibit a tendency to attribute negative meaning to neutral stimuli, and enhanced processing of mood-congruent stimuli. However, evidence thus far has been inconsistent. In this study, we sought to identify both differential interpretation of neutral information as well as emotion processing biases associated with depression.

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Human brain networks that encode variation in mood on naturalistic timescales remain largely unexplored. Here we combine multi-site, semi-chronic, intracranial electroencephalography recordings from the human limbic system with machine learning methods to discover a brain subnetwork that correlates with variation in individual subjects' self-reported mood over days. First we defined the subnetworks that influence intrinsic brain dynamics by identifying regions that showed coordinated changes in spectral coherence.

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Background: Healthy aging is associated with a decline in multiple functional domains including perception, attention, short and long-term memory, reasoning, decision-making, as well as cognitive and motor control functions; all of which are significantly modulated by an individual's level of alertness. The control of alertness also significantly declines with age and contributes to increased lapses of attention in everyday life, ranging from minor memory slips to a lack of vigilance and increased risk of falls or motor-vehicle accidents. Several experimental behavioral therapies designed to remediate age-related cognitive decline have been developed, but differ widely in content, method and dose.

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Background: Mood disorders are dynamic disorders characterized by multimodal symptoms. Clinical assessment of symptoms is currently limited to relatively sparse, routine clinic visits, requiring retrospective recollection of symptoms present in the weeks preceding the visit. Novel advances in mobile tools now support ecological momentary assessment of mood, conducted frequently using mobile devices, outside the clinical setting.

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Article Synopsis
  • As people get older, it becomes harder for them to stay focused and perform tasks well, which affects their learning and skills.
  • Some past studies showed that brain training can help those with brain injuries become more alert and better at thinking.
  • New experiments found that training to improve alertness helped older adults perform better in tasks that require thinking and even learn new skills faster.
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Individuals with Parkinson's disease (PD) commonly demonstrate lateralized spatial biases, which affect daily functioning. Those with PD with initial motor symptoms on the left body side (LPD) have reduced leftward attention, whereas PD with initial motor symptoms on the right side (RPD) may display reduced rightward attention. We investigated whether a sustained attention training program could help reduce these spatial biases.

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Studies have shown that individuals with hemianopia tend to bisect a line toward their blind, contralesional visual field, termed the hemianopic line bisection error (HLBE). One theory proposes that the HLBE is a perceptual distortion resulting from expansion of the central region of visual space. If true, perceptual expansions of the central regions in the intact hemifield should also be present and observable across different tasks.

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The primary objective of this review article is to summarize how the neuroscience of brain plasticity, exploiting new findings in fundamental, integrative and cognitive neuroscience, is changing the therapeutic landscape for professional communities addressing brain-based disorders and disease. After considering the neurological bases of training-driven neuroplasticity, we shall describe how this neuroscience-guided perspective distinguishes this new approach from (a) the more-behavioral, traditional clinical strategies of professional therapy practitioners, and (b) an even more widely applied pharmaceutical treatment model for neurological and psychiatric treatment domains. With that background, we shall argue that neuroplasticity-based treatments will be an important part of future best-treatment practices in neurological and psychiatric medicine.

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Many individuals with traumatic brain injury (TBI) suffer difficulty regulating fundamental aspects of attention (focus, sustained attention) and may also exhibit hypo- or hyper-states of alertness. Deficits in the state of attention may underlie or exacerbate higher order executive dysfunction. Recent studies indicate that computerized cognitive training targeting attentional control and alertness can ameliorate attention deficits evident in patients with TBI or acquired brain injury.

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Background: Spatial neglect is a frequent and debilitating consequence of acquired brain injury and currently has no widely accepted standard of care. While previous interventions for spatial neglect have targeted patients' overt spatial deficits (e.g.

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In addition to deficits in spatial attention, individuals with persistent spatial neglect almost universally exhibit nonspatially lateralized deficits in sustained and selective attention, and working memory. However, nonspatially lateralized deficits in neglect have received considerably less attention in the literature than deficits in spatial attention. This is in spite of the fact that nonspatially lateralized deficits better predict the chronicity and functional disability associated with neglect than spatially lateralized deficits.

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Prominent deficits in spatial attention evident in patients with hemispatial neglect are often accompanied by equally prominent deficits in non-spatial attention (e.g., poor sustained and selective attention, pronounced vigilance decrement).

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The aims of the present study were to investigate the respective roles that object- and viewer-based reference frames play in reorienting visual attention, and to assess their influence after unilateral brain injury. To do so, we studied 16 right hemisphere injured (RHI) and 13 left hemisphere injured (LHI) patients. We used a cueing design that manipulates the location of cues and targets relative to a display comprised of two rectangles (i.

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Amelioration of the rightward spatial attention bias in patients with hemispatial neglect following manipulations of non-spatial attention suggests that spatial attention and mechanisms related to the regulation of attention are interrelated. Studies in normal, healthy subjects have shown similar modulation in spatial bias following tonic and phasic changes in attention suggesting that this interaction is a general mechanism of attention rather than a curiosity of the neglect disorder. The current study examined this attentional interaction to determine if perceptual processes favoring one hemisphere over the other are affected by this relationship.

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Hemispatial neglect is a debilitating disorder marked by a constellation of spatial and non-spatial attention deficits. Patients' alertness deficits have shown to interact with lateralized attention processes and correspondingly, improving tonic/general alertness as well as phasic/moment-to-moment alertness has shown to ameliorate spatial bias. However, improvements are often short-lived and inconsistent across tasks and patients.

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Despite profound inattention to the side of space opposite a brain lesion in patients with unilateral neglect, priming studies demonstrate that undetected stimuli are capable of influencing subsequent behaviour. However, the nature of implicit processing of neglected stimuli is poorly understood. In the current study, we examined implicit processing in five patients with neglect using both visual search and priming methods.

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