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1.
Neuroimage ; 292: 120604, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38604537

ABSTRACT

Despite its widespread use, resting-state functional magnetic resonance imaging (rsfMRI) has been criticized for low test-retest reliability. To improve reliability, researchers have recommended using extended scanning durations, increased sample size, and advanced brain connectivity techniques. However, longer scanning runs and larger sample sizes may come with practical challenges and burdens, especially in rare populations. Here we tested if an advanced brain connectivity technique, dynamic causal modeling (DCM), can improve reliability of fMRI effective connectivity (EC) metrics to acceptable levels without extremely long run durations or extremely large samples. Specifically, we employed DCM for EC analysis on rsfMRI data from the Human Connectome Project. To avoid bias, we assessed four distinct DCMs and gradually increased sample sizes in a randomized manner across ten permutations. We employed pseudo true positive and pseudo false positive rates to assess the efficacy of shorter run durations (3.6, 7.2, 10.8, 14.4 min) in replicating the outcomes of the longest scanning duration (28.8 min) when the sample size was fixed at the largest (n = 160 subjects). Similarly, we assessed the efficacy of smaller sample sizes (n = 10, 20, …, 150 subjects) in replicating the outcomes of the largest sample (n = 160 subjects) when the scanning duration was fixed at the longest (28.8 min). Our results revealed that the pseudo false positive rate was below 0.05 for all the analyses. After the scanning duration reached 10.8 min, which yielded a pseudo true positive rate of 92%, further extensions in run time showed no improvements in pseudo true positive rate. Expanding the sample size led to enhanced pseudo true positive rate outcomes, with a plateau at n = 70 subjects for the targeted top one-half of the largest ECs in the reference sample, regardless of whether the longest run duration (28.8 min) or the viable run duration (10.8 min) was employed. Encouragingly, smaller sample sizes exhibited pseudo true positive rates of approximately 80% for n = 20, and 90% for n = 40 subjects. These data suggest that advanced DCM analysis may be a viable option to attain reliable metrics of EC when larger sample sizes or run times are not feasible.


Subject(s)
Brain , Connectome , Magnetic Resonance Imaging , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/standards , Sample Size , Connectome/methods , Connectome/standards , Reproducibility of Results , Brain/diagnostic imaging , Brain/physiology , Adult , Female , Male , Rest/physiology , Time Factors
3.
Neurooncol Pract ; 8(4): 485-496, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34267923

ABSTRACT

BACKGROUND: The COVID-19 pandemic induced rapid adoption of telemedicine services for neuro-oncology patients at an increased risk of infection. Neuropsychological assessment is important to neuro-oncology care yet challenging to complete outside of a structured testing environment. Teleneuropsychology (TNP) has been explored in limited populations and proven feasible and reliable. Conducting TNP visits directly to patients' home (DTH) had minimal prior study. METHODS: We used two voluntary surveys to examine acceptance (patients) and feasibility (providers) of DTH-TNP at two regionally diverse medical institutions providing neuropsychological services to neuro-oncology patients from April to September 2020. RESULTS: A total of 119 patients were scheduled during the study period, 79 of whom completed neuropsychological testing via DTH-TNP. Neuropsychology providers completed surveys on 68 of these encounters (86%). In 98% of cases, neuropsychologists were able to achieve or partially achieve the individually defined goals of their assessment. Common problems reported included patient dysregulation (16%) and slow/unreliable internet (15%). Of the 52 patients who responded, 98% were satisfied with the DTH-TNP experience, and 92% would recommend the virtual visit to others. All respondents felt understood by the examiner (100%) and the majority denied technical difficulties (90%), communication challenges (94%), or privacy concerns (98%). Patients reported reduced risk of infection and saved travel time as favorable aspects of DTH-TNP. CONCLUSIONS: These preliminary results suggest neuro-oncology patients find DTH-TNP acceptable and neuropsychologists find it a feasible practice, while also recognizing its limitations. Results suggest that further study of DTH-TNP (eg, reliability, validity) for neuro-oncology patients is warranted.

4.
Neurooncol Pract ; 7(5): 498-506, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33014390

ABSTRACT

BACKGROUND: A diagnosis of cancer may increase mortality salience and provoke death-related distress. Primary brain tumor (PBT) patients may be at particular risk for such distress given the certainty of tumor progression, lack of curative treatments, and poor survival rates. This study is the first to examine the prevalence of death-related distress and its correlates in PBT patients. METHODS: Adult PBT patients (N = 105) enrolled in this cross-sectional study and completed the Death Distress Scale (subscales: Death Depression, Death Anxiety, Death Obsession), Generalized Anxiety Disorder-7, and Patient Health Questionnaire-9. Prevalence and predictors of death-related distress, and the relationships of demographic variables to clusters of distress, were explored. RESULTS: The majority of PBT patients endorsed clinically significant death-related distress in at least one domain. Death anxiety was endorsed by 81%, death depression by 12.5%, and death obsession by 10.5%. Generalized anxiety was the only factor associated with global death-related distress. Cluster analysis yielded 4 profiles: global distress, emotional distress, resilience, and existential distress. Participants in the resilience cluster were significantly further out from diagnosis than those in the existential distress cluster. There were no differences in cluster membership based on age, sex, or tumor grade. CONCLUSIONS: PBT patients appear to have a high prevalence of death-related distress, particularly death anxiety. Further, 4 distinct profiles of distress were identified, supporting the need for tailored approaches to addressing death-related distress. A shift in clusters of distress based on time since diagnosis also suggest the need for future longitudinal assessment.

5.
Appl Neuropsychol Adult ; 27(5): 393-402, 2020.
Article in English | MEDLINE | ID: mdl-30714410

ABSTRACT

Adult primary brain tumor (PBT) survivors report persistent cognitive difficulties before, during, and after treatment, which are problematic for everyday functioning. Cognitive domains often affected by cancer treatment appear to be attention and executive functioning (EF). One validated measure developed to assess an individual's EF within daily living is the Behavior Rating Inventory of Executive Function-Adult (BRIEF-A). To date, no published research has investigated the EF profile of PBT patients using the BRIEF-A. Seventy-four PBT patients completed the BRIEF-A. Descriptive analyses were conducted to determine the self-reported EF profile in PBT patients. T-tests preliminarily compared the performance of PBT patients to four other comparison groups: mild cognitive impairment (MCI; n = 23), attention-deficit/hyperactivity disorder-unmedicated (ADHD-U; n = 27), traumatic brain injury (TBI; n = 23), and healthy controls (HC; n = 26). PBT BRIEF-A group means were average across subscales and indexes, yet the prevalence of significant elevations ranged from 12 to 50%. The Metacognition Index demonstrated 38% elevation prevalence compared to 22% in Behavioral Regulation. Approximately 61% of the sample had at least one clinically elevated scaled score. PBT patients reported significantly more EF impairment than HC and significantly less than ADHD-U. No significant differences were found between the PBT and MCI groups or PBT and TBI groups. Despite group means not reaching clinical impairment, a substantial proportion of patients with PBTs endorse executive dysfunction. Elevations were most prominent in metacognitive abilities over behavioral dysregulation. Notably, the EF profile of PBT patients was remarkably similar to that of MCI and TBI, increased when compared to HC, and well below ADHD-U.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Brain Injuries, Traumatic/physiopathology , Brain Neoplasms/complications , Cognitive Dysfunction/etiology , Cognitive Dysfunction/physiopathology , Executive Function/physiology , Neuropsychological Tests , Adult , Aged , Aged, 80 and over , Attention Deficit Disorder with Hyperactivity/complications , Behavior Rating Scale , Brain Injuries, Traumatic/complications , Cancer Survivors , Female , Humans , Male , Middle Aged , Young Adult
6.
Glob Adv Health Med ; 8: 2164956119879872, 2019.
Article in English | MEDLINE | ID: mdl-31632841

ABSTRACT

BACKGROUND: Health-care professional (HCP) students experience high levels of burnout, characterized by work- and school-related stress. Burnout is associated with a host of negative psychological and health outcomes. It may also contribute to cognitive dysfunction and decreased work productivity and may be related to trait mindfulness. This study cross-sectionally explored psychological distress and its correlates in a sample of interdisciplinary HCP students using cluster analysis. METHOD: Fifty-seven interdisciplinary HCP students completed validated measures of burnout, depressive and anxiety symptoms, perceived stress, and rumination, which were entered into a cluster analysis. A neuropsychological test measured executive function; validated questionnaires assessed work productivity and trait mindfulness. Relationships between cluster membership and classroom productivity, executive function, and trait mindfulness were investigated. RESULTS: Burnout, depressive symptoms, and perceived stress were reported at high rates in this sample. The cluster analysis yielded 4 clusters, categorized as follows: Healthy, Ruminative Healthy, Moderate Distress, and High Distress. Cluster membership significantly differed based on trait mindfulness and classroom productivity. Trait mindfulness was related to classroom productivity. Although not significant, there were small to medium associations between executive function and both cluster membership and trait mindfulness. DISCUSSION: Cluster membership was highly related to trait mindfulness and classroom productivity, suggesting these are important correlates of psychological distress in HCP students. Taken together, these results underscore the need for interventions, especially ones that are mindfulness-based, to manage stress and work-relevant functioning in HCP students.

7.
Neurooncol Pract ; 6(4): 289-296, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31386070

ABSTRACT

BACKGROUND: Neurocognitive assessments have become integral to comprehensive neuro-oncology care. Existing screening tools may be insensitive to cognitive changes caused by medical treatments. Research supports the clinical value and psychometric properties of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in various medical populations; however, there is minimal evidence for its use in neuro-oncology. The purpose of the current study was to further explore the cognitive profile of patients with primary brain tumor (PBT) using the RBANS and to assess rates of below-expectation performance compared to normative data and estimated intellectual functioning. METHODS: Data were collected on 82 PBT patients (54% male; age range, 19-81 years). All patients were administered the RBANS-Update and the Advanced Clinical Solutions-Test of Premorbid Functioning (TOPF) according to standardized instructions. Cognitive strengths and weaknesses were identified for PBT patients. Descriptive analyses, t tests, and chi-squared tests were utilized to identify and compare cognitive profiles. RESULTS: Overall, cognitive performance was low average for PBT patients. When compared to standardization data, PBT patients performed significantly worse across all 5 RBANS indexes, with Attention and Memory showing the largest discrepancies. Estimated intelligence analyses reflected greater deficits in cognitive functioning than when compared to a normal distribution. CONCLUSIONS: Preliminary research demonstrates the RBANS is an efficient screening tool to assess cognitive deficits in PBT patients. Data also support the importance of comparison to self, rather than normative distribution in ensuring proper identification and classification of patients.

8.
PLoS One ; 14(7): e0219862, 2019.
Article in English | MEDLINE | ID: mdl-31323050

ABSTRACT

In social contexts, the dynamic nature of others' emotions places unique demands on attention and emotion regulation. Mindfulness, characterized by heightened and receptive moment-to-moment attending, may be well-suited to meet these demands. In particular, mindfulness may support more effective cognitive control in social situations via efficient deployment of top-down attention. To test this, a randomized controlled study examined effects of mindfulness training (MT) on behavioral and neural (event-related potentials [ERPs]) responses during an emotional go/no-go task that tested cognitive control in the context of emotional facial expressions that tend to elicit approach or avoidance behavior. Participants (N = 66) were randomly assigned to four brief (20 min) MT sessions or to structurally equivalent book learning control sessions. Relative to the control group, MT led to improved discrimination of facial expressions, as indexed by d-prime, as well as more efficient cognitive control, as indexed by response time and accuracy, and particularly for those evidencing poorer discrimination and cognitive control at baseline. MT also produced better conflict monitoring of behavioral goal-prepotent response tendencies, as indexed by larger No-Go N200 ERP amplitudes, and particularly so for those with smaller No-Go amplitude at baseline. Overall, findings are consistent with MT's potential to enhance deployment of early top-down attention to better meet the unique cognitive and emotional demands of socioemotional contexts, particularly for those with greater opportunity for change. Findings also suggest that early top-down attention deployment could be a cognitive mechanism correspondent to the present-oriented attention commonly used to explain regulatory benefits of mindfulness more broadly.


Subject(s)
Cognition , Emotions , Mindfulness , Adolescent , Adult , Electroencephalography , Facial Expression , Female , Humans , Male , Middle Aged , Research , Self Report , Young Adult
9.
Adv Med Educ Pract ; 8: 591-597, 2017.
Article in English | MEDLINE | ID: mdl-28860889

ABSTRACT

PURPOSE: Burnout has been documented at high levels in medical residents with negative effects on performance. Some dispositional qualities, like mindfulness, may protect against burnout. The purpose of the present study was to assess burnout prevalence among internal medicine residents at a single institution, examine the relationship between mindfulness and burnout, and provide preliminary findings on the relation between burnout and performance evaluations in internal medicine residents. METHODS: Residents (n = 38) completed validated measures of burnout at three time points separated by 2 months and a validated measure of dispositional mindfulness at baseline. Program director end-of-year performance evaluations were also obtained on 22 milestones used to evaluate internal medicine resident performance; notably, these milestones have not yet been validated for research purposes; therefore, the investigation here is exploratory. RESULTS: Overall, 71.1% (n = 27) of the residents met criteria for burnout during the study. Lower scores on the "acting with awareness" facet of dispositional mindfulness significantly predicted meeting burnout criteria χ2(5) = 11.88, p = 0.04. Lastly, meeting burnout criteria significantly predicted performance on three of the performance milestones, with positive effects on milestones from the "system-based practices" and "professionalism" domains and negative effects on a milestone from the "patient care" domain. CONCLUSION: Burnout rates were high in this sample of internal medicine residents and rates were consistent with other reports of burnout during medical residency. Dispositional mindfulness was supported as a protective factor against burnout. Importantly, results from the exploratory investigation of the relationship between burnout and resident evaluations suggested that burnout may improve performance on some domains of resident evaluations while compromising performance on other domains. Implications and directions for future research are discussed.

10.
Psychol Assess ; 28(7): 803-18, 2016 07.
Article in English | MEDLINE | ID: mdl-27078183

ABSTRACT

Improvements in stable, or dispositional, mindfulness are often assumed to accrue from mindfulness training and to account for many of its beneficial effects. However, research examining these assumptions has produced mixed findings, and the relation between dispositional mindfulness and mindfulness training is actively debated. A comprehensive meta-analysis was conducted on randomized controlled trials (RCTs) of mindfulness training published from 2003-2014 to investigate whether (a) different self-reported mindfulness scale dimensions change as a result of mindfulness training, (b) key aspects of study design (e.g., control condition type, population type, and intervention type) moderate training-related changes in dispositional mindfulness scale dimensions, and (c) changes in mindfulness scale dimensions are associated with beneficial changes in mental health outcomes. Scales from widely used dispositional mindfulness measures were combined into 5 categories for analysis: Attention, Description, Nonjudgment, Nonreactivity, and Observation. A total of 88 studies (n = 5,787) were included. Changes in scale dimensions of mindfulness from pre to post mindfulness training produced mean difference effect sizes ranging from small to moderate (g = 0.28-0.49). Consistent with the theorized role of improvements in mindfulness in training outcomes, changes in dispositional mindfulness scale dimensions were moderately correlated with beneficial intervention outcomes (r = .27-0.30), except for the Observation dimension (r = .16). Overall, moderation analyses revealed inconsistent results, and limitations of moderator analyses suggest important directions for future research. We discuss how the findings can inform the next generation of mindfulness assessment. (PsycINFO Database Record


Subject(s)
Mindfulness , Psychological Tests , Self Report , Attention , Humans , Judgment , Meditation/psychology , Observation
11.
Phytopathology ; 100(12): 1307-14, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20718667

ABSTRACT

Fungus gnats have been shown to transmit a variety of plant-pathogenic fungi that produce aerial dispersal stages. However, few studies have examined potential interactions between fungus gnats and oomycetes, including Pythium spp. A series of laboratory experiments were conducted to determine whether fungus gnat adults are vectors of several common greenhouse Pythium spp., including Pythium aphanidermatum, P. irregulare, and P. ultimum. An additional objective was to determine whether P. aphanidermatum can be maintained transstadially in the gut of a fungus gnat larva through the pupal stadium to be transmitted by the subsequent adult. Adult fungus gnats did not pick up infectious Pythium propagules from diseased plants and transmit them to healthy plants in any experiment. Species-specific primers and a probe for real-time polymerase chain reaction were developed to detect the presence of P. aphanidermatum DNA in fungus gnat tissue samples. P. aphanidermatum DNA was detectable in the larval and pupal stages; however, none was detected in adult fungus gnats. These results are in agreement with previous studies that have suggested that adult fungus gnats are unlikely vectors of Pythium spp.


Subject(s)
Impatiens/microbiology , Plant Diseases/microbiology , Pythium/pathogenicity , Seedlings/microbiology , DNA Primers , DNA, Fungal/genetics , DNA, Fungal/isolation & purification , Gene Amplification , Geography , Geranium/microbiology , Pythium/isolation & purification , United States
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