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1.
Brain Behav ; 14(2): e3434, 2024 02.
Article in English | MEDLINE | ID: mdl-38383037

ABSTRACT

BACKGROUND: Multiple object tracking (MOT) is often used as a lab-based paradigm for investigating goal-driven attention as an indicator for "real-world" attention in tasks such as sport. When exploring MOT performance in the context of sporting expertise, we typically observe that individuals with sporting expertise outperform non-sporting individuals. There are a number of general explanations for performance differences such as cognitive transfer effects; however, the potential neurophysiological mechanisms explaining the relationship between sporting expertise and performance differences in MOT are not clear. Based on the role occipital alpha (posterior oscillations usually around 8-12 Hz) has been shown to have in visuospatial attention, the aim of this study was to examine whether individual differences in occipital peak alpha frequency (PAF) mediate the relationship between sporting expertise and performance in two object tracking tasks: a standard MOT task and a visuomotor-controlled object tracking task (multiple object avoidance [MOA]). METHOD: Using electroencephalography (EEG), participants, who either played sport competitively or did not, had their posterior PAF measured at rest (eyes closed) across a 2-min window. They completed the two tasks separately from the resting EEG measures. RESULTS: Those who engaged in sport performed better in the MOT and MOA tasks and had higher PAF. Higher PAF predicted superior MOT performance. The mediation analysis revealed that sporting individuals had significantly higher PAF, and this was in turn related to superior MOT performance. CONCLUSIONS: It is suggested that PAF is a possible neurophysiological mediating mechanism as to why sporting individuals have superior MOT performance. There was no evidence that PAF mediated the relationship between sporting expertise and visuomotor MOA performance. Explanations and implications are discussed, and unanswered questions are proposed.


Subject(s)
Attention , Sports , Humans , Attention/physiology , Electroencephalography
2.
RSC Adv ; 13(13): 8496-8501, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36926306

ABSTRACT

A carboxylesterase derived from Sulfolobus solfataricus P1 was immobilized onto an epoxy-activated Sepharose resin via non-canonical amino acids. The immobilized enzyme exhibited heightened performance in organic solvents, recyclability, and stability at room temperature for over two years. The incorporation of a non-canonical amino acid afforded a high degree of control over the bioorthogonal immobilization reaction. These results indicate that the specificity conferred by genetic code expansion produces advantages in protein immobilization and broadens the utility of such proteins to non-biological settings.

3.
J Matern Fetal Neonatal Med ; 36(1): 2162820, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36597833

ABSTRACT

OBJECTIVE: Rates of neonatal abstinence syndrome/neonatal opioid withdrawal syndrome (NAS/NOWS), a withdrawal syndrome from opioids and other substances resulting from intrauterine exposure, have been increasing exponentially in the U.S. To improve health outcomes, it is important to understand population health risks, including rehospitalization and related diagnoses, using current data. This study will compare and describe the rates of rehospitalization, the demographic characteristics and the rehospitalization diagnoses and age at diagnosis between the infants affected by NAS/NOWS to those sampled who were unaffected. This study will also describe the frequency of NAS/NOWS births per year along with a yearly comparison of readmissions in those affected by NAS/NOWS to those who were not (2016-2020). METHODS: Health claims data were used to conduct a case/control study. Diagnosis codes for neonatal withdrawal syndrome/NAS/NOWS (P04.49 or P96.1 and P96.1 alone) from 1 October 2015 to 1 June 2021 were extracted, and controls were case-matched based on month/year of birth. Rehospitalizations following birth and the related diagnoses were described and grouped using the Agency of Healthcare Research Quality Clinical Classifications Software Refined Frequency distribution. The chi-square test of association and generalized estimating equation modeling were used for data analysis. RESULTS: Infants affected by NAS/NOWS are 2.7 times more likely to have a rehospitalization. White, non-Hispanic neonates (OR = 1.5; p = .007) and those infants residing in rural areas (OR = 1.9; p < .001) were disproportionately affected. We identified a host of admission diagnoses with increased prevalence in infants affected by NAS/NOWS when compared to those who were not affected (e.g. infectious diseases, feeding disorders). CONCLUSIONS: Infants with NAS/NOWS are at increased risk of rehospitalization with a host of diagnoses, and specific demographic groups (White, rural) are more highly affected.


Subject(s)
Neonatal Abstinence Syndrome , Opioid-Related Disorders , Infant, Newborn , Humans , Infant , Neonatal Abstinence Syndrome/epidemiology , Neonatal Abstinence Syndrome/diagnosis , Patient Readmission , Case-Control Studies , Analgesics, Opioid/adverse effects , Health Facilities , Opioid-Related Disorders/epidemiology
4.
Pharmaceutics ; 14(12)2022 Dec 16.
Article in English | MEDLINE | ID: mdl-36559319

ABSTRACT

Protein modification with non-canonical amino acids (ncAAs) represents a useful technology to afford homogenous samples of bioconjugates with site-specific modification. This technique can be directly applied to the detection of aberrant SUMOylation patterns, which are often indicative of disease states. Modified SUMO-trapping proteins, consisting of a catalytically inactive ULP1 fragment (UTAG) fused to the maltose-binding protein MBP, are useful reagents for the binding and labeling of SUMOylated proteins. Mutation of this UTAG fusion protein to facilitate amber suppression technologies for the genetic incorporation of ncAAs was assessed to provide a functional handle for modification. Ultimately, two sites in the maltose-binding protein (MBP) fusion were identified as ideal for incorporation and bioconjugation without perturbation to the SUMO-trapping ability of the UTAG protein. This functionality was then employed to label SUMOylated proteins in HeLa cells and demonstrate their enrichment in the nucleus. This modified UTAG-MBP-ncAA protein has far-reaching applications for both diagnostics and therapeutics.

5.
PeerJ ; 10: e13031, 2022.
Article in English | MEDLINE | ID: mdl-35261822

ABSTRACT

Although the Multiple Object Tracking (MOT) task is a widely used experimental method for studying divided attention, tracking objects in the real world usually looks different. For example, in the real world, objects are usually clearly distinguishable from each other and also possess different movement patterns. One such case is tracking groups of creatures, such as tracking fish in an aquarium. We used movies of fish in an aquarium and measured general tracking performance in this task (Experiment 1). In Experiment 2, we compared tracking accuracy within-subjects in fish tracking, tracking typical MOT stimuli, and in a third condition using standard MOT uniform objects which possessed movement patterns similar to the real fish. This third condition was added to further examine the impact of different motion characteristics on tracking performance. Results within a Bayesian framework showed that tracking real fish shares similarities with tracking simple objects in a typical laboratory MOT task. Furthermore, we observed a close relationship between performance in both laboratory MOT tasks (typical and fish-like) and real fish tracking, suggesting that the commonly used laboratory MOT task possesses a good level of ecological validity.


Subject(s)
Motion Perception , Rubella , Humans , Bayes Theorem , Attention , Research Design
6.
Behav Res Methods ; 54(3): 1508-1529, 2022 06.
Article in English | MEDLINE | ID: mdl-34786653

ABSTRACT

Performance in everyday tasks, such as driving and sport, requires allocation of attention to task-relevant information and the ability to inhibit task-irrelevant information. Yet there are individual differences in this attentional function ability. This research investigates a novel task for measuring attention for action, called the Multiple Object Avoidance task (MOA), in its relation to the everyday tasks of driving and sport. The aim in Study 1 was to explore the efficacy of the MOA task to predict simulated driving behaviour and hazard perception. Whilst also investigating its test-retest reliability and how it correlates to self-report driving measures. We found that superior performance in the MOA task predicted simulated driving performance in complex environments and was superior at predicting performance compared to the Useful Field of View task. We found a moderate test-retest reliability and a correlation between the attentional lapses subscale of the Driving Behaviour Questionnaire. Study 2 investigated the discriminative power of the MOA in sport by exploring performance differences in those that do and do not play sports. We also investigated if the MOA shared attentional elements with other measures of visual attention commonly attributed to sporting expertise: Multiple Object Tracking (MOT) and cognitive processing speed. We found that those that played sports exhibited superior MOA performance and found a positive relationship between MOA performance and Multiple Object Tracking performance and cognitive processing speed. Collectively, this research highlights the utility of the MOA when investigating visual attention in everyday contexts.


Subject(s)
Cognition , Humans , Reproducibility of Results
7.
Clin Neurophysiol ; 133: 111-125, 2022 01.
Article in English | MEDLINE | ID: mdl-34839236

ABSTRACT

OBJECTIVE: Prospective memory (PM) -the memory of delayed intentions- is impacted by age-related cognitive decline. The current event-related potential study investigates neural mechanisms underpinning typical and atypical (Mild Cognitive Impairment, MCI) age-related decline in PM. METHODS: Young adults (YA, n = 30, age = 24.7, female n = 13), healthy older adults (OA, n = 39, age = 72.87, female n = 24) and older adults with MCI (n = 27, age = 77.54, female n = 12) performed two event-based PM tasks (perceptual, conceptual) superimposed on an ongoing working memory task. Electroencephalographic data was recorded from 128 electrodes. Groups were compared for P2 (higher order perceptual processing), N300/frontal positivity (cue detection), the parietal positivity (retrieval), reorienting negativity (RON; attention shifting). RESULTS: Participants with MCI had poorer performance (ongoing working memory task, conceptual PM), lower P2 amplitudes, and delayed RON (particularly for perceptual PM) than YA and OA. MCI had lower parietal positivity relative to YA only. YA had earlier latencies for the parietal positivity than MCI and OA, and lower amplitudes for N300 (than OA) and frontal positivity (than OA and MCI). CONCLUSIONS: Impaired attention and working memory may underpin PM deficits in MCI. SIGNIFICANCE: This is the first study to document the role of RON in PM and to investigate neurophysiological mechanisms underpinning PM in MCI.


Subject(s)
Aging/physiology , Brain/physiopathology , Cognitive Dysfunction/physiopathology , Evoked Potentials/physiology , Memory, Short-Term/physiology , Adult , Aged , Aged, 80 and over , Aging/psychology , Cognitive Dysfunction/psychology , Electroencephalography , Female , Humans , Male , Memory, Episodic , Neuropsychological Tests , Young Adult
8.
Cogn Res Princ Implic ; 6(1): 47, 2021 06 26.
Article in English | MEDLINE | ID: mdl-34175977

ABSTRACT

Visual search in dynamic environments, for example lifeguarding or CCTV monitoring, has several fundamentally different properties to standard visual search tasks. The visual environment is constantly moving, a range of items could become targets and the task is to search for a certain event. We developed a novel task in which participants were required to search static and moving displays for an orientation change thus capturing components of visual search, multiple object tracking and change detection paradigms. In Experiment 1, we found that the addition of moving distractors slowed participants' response time to detect an orientation changes in a moving target, showing that the motion of distractors disrupts the rapid detection of orientation changes in a moving target. In Experiment 2 we found that, in displays of both moving and static objects, response time was slower if a moving object underwent a change than if a static object did, thus demonstrating that motion of the target itself also disrupts the detection of an orientation change. Our results could have implications for training in real-world occupations where the task is to search a dynamic environment for a critical event. Moreover, we add to the literature highlighting the need to develop lab-based tasks with high experimental control from any real-world tasks researchers may wish to investigate rather than extrapolating from static visual search tasks to more dynamic environments.


Subject(s)
Motion Perception , Attention , Humans , Motion , Pattern Recognition, Visual , Reaction Time
9.
Neuropsychologia ; 157: 107887, 2021 07 16.
Article in English | MEDLINE | ID: mdl-33974956

ABSTRACT

Prior research has focused on EEG differences across age or EEG differences across cognitive tasks/eye tracking. There are few studies linking age differences in EEG to age differences in behavioural performance which is necessary to establish how neuroactivity corresponds to successful and impaired ageing. Eighty-six healthy participants completed a battery of cognitive tests and eye-tracking measures. Resting state EEG (n = 75, 31 young, 44 older adults) was measured for delta, theta, alpha and beta power as well as for alpha peak frequency. Age deficits in cognition were aligned with the literature, showing working memory and inhibitory deficits along with an older adult advantage in vocabulary. Older adults showed poorer eye movement accuracy and response times, but we did not replicate literature showing a greater age deficit for antisaccades than for prosaccades. We replicated EEG literature showing lower alpha peak frequency in older adults but not literature showing lower alpha power. Older adults also showed higher beta power and less parietal alpha power asymmetry than young adults. Interaction effects showed that better prosaccade performance was related to lower beta power in young adults but not in older adults. Performance at the trail making test part B (measuring task switching and inhibition) was improved for older adults with higher resting state delta power but did not depend on delta power for young adults. It is argued that individuals with higher slow-wave resting EEG may be more resilient to age deficits in tasks that utilise cross-cortical processing.


Subject(s)
Electroencephalography , Eye Movements , Aged , Brain , Cognition , Humans , Rest , Young Adult
10.
J Exp Psychol Appl ; 27(2): 352-368, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33749301

ABSTRACT

Visual search is increasingly being explored in dynamic, real-world environments. This includes swimming pools, where lifeguards have shown superior drowning detection in simulated environments. Here, we explored if lifeguard superiority is observed in real-life scenes of a busy swimming pool. Experiment 1 required participants to identify real-life distressed swimmers in clips of busy pool activity via a touchscreen interface. Experiment 2 sought to replicate the first study, with the inclusion of eye-movement measures. Experiment 3 varied the methodology, using an occlusion method where clips were frozen and blurred shortly after target onset. The results demonstrated an experience effect, with lifeguards detecting distressed swimmers more often and faster than nonlifeguards. No clear differences were found in the eye-movements between groups; thus, we cannot conclude that the lifeguards' faster responses are due to better scanning strategies. The different methodological approaches revealed the occlusion method to have the larger effect size, supporting the growing evidence that occlusion may be a better test for dynamic target detection than traditional response-time tests. This research demonstrates that the clear lifeguard experience effect generalizes to real-life pool environments with a large number of swimmers and real incidents. It could be used to inform lifeguard training tools and assessments. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Subject(s)
Drowning , Swimming Pools , Eye Movements , Humans , Reaction Time
11.
Carbon Balance Manag ; 16(1): 9, 2021 Mar 30.
Article in English | MEDLINE | ID: mdl-33786694

ABSTRACT

BACKGROUND: There are high estimates of the potential climate change mitigation opportunity of using wood products. A significant part of those estimates depends on long-lived wood products in the construction sector replacing concrete, steel, and other non-renewable goods. Often the climate change mitigation benefits of this substitution are presented and quantified in the form of displacement factors. A displacement factor is numerically quantified as the reduction in emissions achieved per unit of wood used, representing the efficiency of biomass in decreasing greenhouse gas emissions. The substitution benefit for a given wood use scenario is then represented as the estimated change in emissions from baseline in a study's modelling framework. The purpose of this review is to identify and assess the central economic and technical assumptions underlying forest carbon accounting and life cycle assessments that use displacement factors or similar simple methods. MAIN TEXT: Four assumptions in the way displacement factors are employed are analyzed: (1) changes in harvest or production rates will lead to a corresponding change in consumption of wood products, (2) wood building products are substitutable for concrete and steel, (3) the same mix of products could be produced from increased harvest rates, and (4) there are no market responses to increased wood use. CONCLUSIONS: After outlining these assumptions, we conclude suggesting that many studies assessing forest management or products for climate change mitigation depend on a suite of assumptions that the literature either does not support or only partially supports. Therefore, we encourage the research community to develop a more sophisticated model of the building sectors and their products. In the meantime, recognizing these assumptions has allowed us to identify some structural, production, and policy-based changes to the construction industry that could help realize the climate change mitigation potential of wood products.

12.
Nat Chem Biol ; 16(12): 1403-1410, 2020 12.
Article in English | MEDLINE | ID: mdl-32868895

ABSTRACT

The nuclear receptor-binding SET domain (NSD) family of histone methyltransferases is associated with various malignancies, including aggressive acute leukemia with NUP98-NSD1 translocation. While NSD proteins represent attractive drug targets, their catalytic SET domains exist in autoinhibited conformation, presenting notable challenges for inhibitor development. Here, we employed a fragment-based screening strategy followed by chemical optimization, which resulted in the development of the first-in-class irreversible small-molecule inhibitors of the nuclear receptor-binding SET domain protein 1 (NSD1) SET domain. The crystal structure of NSD1 in complex with covalently bound ligand reveals a conformational change in the autoinhibitory loop of the SET domain and formation of a channel-like pocket suitable for targeting with small molecules. Our covalent lead-compound BT5-demonstrates on-target activity in NUP98-NSD1 leukemia cells, including inhibition of histone H3 lysine 36 dimethylation and downregulation of target genes, and impaired colony formation in an NUP98-NSD1 patient sample. This study will facilitate the development of the next generation of potent and selective inhibitors of the NSD histone methyltransferases.


Subject(s)
Antineoplastic Agents/pharmacology , Enzyme Inhibitors/pharmacology , Gene Expression Regulation, Leukemic , Histone-Lysine N-Methyltransferase/antagonists & inhibitors , Leukocytes/drug effects , Nuclear Pore Complex Proteins/genetics , Oncogene Proteins, Fusion/antagonists & inhibitors , Antineoplastic Agents/chemical synthesis , Binding Sites , Enzyme Inhibitors/chemical synthesis , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Kinetics , Leukemia/drug therapy , Leukemia/enzymology , Leukemia/genetics , Leukemia/pathology , Leukocytes/enzymology , Leukocytes/pathology , Models, Molecular , Myeloid Ecotropic Viral Integration Site 1 Protein/genetics , Myeloid Ecotropic Viral Integration Site 1 Protein/metabolism , Nuclear Pore Complex Proteins/metabolism , Oncogene Proteins, Fusion/genetics , Oncogene Proteins, Fusion/metabolism , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Signal Transduction , Substrate Specificity , Tumor Cells, Cultured
13.
Atten Percept Psychophys ; 82(7): 3544-3557, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32533526

ABSTRACT

Seeing a talker's face can aid audiovisual (AV) integration when speech is presented in noise. However, few studies have simultaneously manipulated auditory and visual degradation. We aimed to establish how degrading the auditory and visual signal affected AV integration. Where people look on the face in this context is also of interest; Buchan, Paré and Munhall (Brain Research, 1242, 162-171, 2008) found fixations on the mouth increased in the presence of auditory noise whilst Wilson, Alsius, Paré and Munhall (Journal of Speech, Language, and Hearing Research, 59(4), 601-615, 2016) found mouth fixations decreased with decreasing visual resolution. In Condition 1, participants listened to clear speech, and in Condition 2, participants listened to vocoded speech designed to simulate the information provided by a cochlear implant. Speech was presented in three levels of auditory noise and three levels of visual blurring. Adding noise to the auditory signal increased McGurk responses, while blurring the visual signal decreased McGurk responses. Participants fixated the mouth more on trials when the McGurk effect was perceived. Adding auditory noise led to people fixating the mouth more, while visual degradation led to people fixating the mouth less. Combined, the results suggest that modality preference and where people look during AV integration of incongruent syllables varies according to the quality of information available.


Subject(s)
Eye Movements , Speech Perception , Auditory Perception , Humans , Speech , Visual Perception
14.
Q J Exp Psychol (Hove) ; 73(5): 799-818, 2020 May.
Article in English | MEDLINE | ID: mdl-31842721

ABSTRACT

The extent to which similar capacity limits in visual attention and visual working memory indicate a common shared underlying mechanism is currently still debated. In the spatial domain, the multiple object tracking (MOT) task has been used to assess the relationship between spatial attention and spatial working memory though existing results have been inconclusive. In three dual task experiments, we examined the extent of interference between attention to spatial positions and memory for spatial positions. When the position monitoring task required keeping track of target identities through colour-location binding, we found a moderate detrimental effect of position monitoring on spatial working memory and an ambiguous interaction effect. However, when this task requirement was removed, load increases in neither task were detrimental to the other. The only very moderate interference effect that remained resided in an interaction between load types but was not consistent with shared capacity between tasks-rather it was consistent with content-related crosstalk between spatial representations. Contrary to propositions that spatial attention and spatial working memory may draw on a common shared set of core processes, these findings indicate that for a purely spatial task, perceptual attention and working memory appear to recruit separate core capacity-limited processes.


Subject(s)
Attention/physiology , Executive Function/physiology , Memory, Short-Term/physiology , Space Perception/physiology , Spatial Memory/physiology , Visual Perception/physiology , Adult , Female , Humans , Male , Young Adult
15.
Perception ; 48(4): 346-355, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30832537

ABSTRACT

Right parietal cortex has recently been linked to the temporal resolution of attention. We therefore sought to investigate whether disruption to right parietal cortex would affect attention to visual stimuli presented for brief durations. Participants performed a visual discrimination task before and after 10 minutes repetitive transcranial magnetic stimulation (1 Hz) to right or central parietal cortex as well as 20 minutes after the second block of trials. Participants reported the spatial frequency of a masked Gabor patch presented for a brief duration of 60, 120, or 240 ms. We calculated error magnitudes by comparing accuracy to a guessing model. We then compared error magnitudes to blocks with no stimulation, producing a measure of baselined performance. Baselined performance was poorer at longer stimulus durations after right parietal than central parietal stimulation, suggesting that right parietal cortex is involved in attention to briefly presented stimuli, particularly in situations where rapid accumulation of visual evidence is needed.


Subject(s)
Attention/physiology , Discrimination, Psychological/physiology , Parietal Lobe/physiology , Pattern Recognition, Visual/physiology , Psychomotor Performance/physiology , Transcranial Magnetic Stimulation/methods , Adolescent , Adult , Female , Humans , Male , Time Factors , Young Adult
16.
Atten Percept Psychophys ; 81(5): 1312-1326, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30761503

ABSTRACT

In standard multiple object tracking (MOT) tasks the relative importance of the targets being tracked is equal. This is atypical of everyday situations in which an individual may need to prioritize one target relative to another and so allocate attention unequally. We report three experiments that examined whether participants could unequally split attention using a modified MOT task in which target priority was manipulated. Specifically, we examined the effect of priority on participants' magnitude of error and used a distribution mixture analysis to investigate how priority affected both participants' probability of losing an item and tracking precision. Experiment 1 (trajectory tracking) revealed a higher magnitude of error and higher proportion of guessing for low- compared with high-priority targets. Experiments 2 (trajectory tracking) and 3 (position tracking) examined how fine-grained this ability is by manipulating target priority at finer increments. In line with Experiment 1, results from both these experiments indicated that participants could split attention unequally. There was some evidence that participants could allocate attention unequally at fine increments, but this was less conclusive. Taken together, these experiments demonstrate participants' ability to distribute attention unequally across multiple moving objects but suggest some limitation with the flexibility of attention allocation.


Subject(s)
Attention , Motion Perception , Female , Goals , Humans , Male , Multitasking Behavior , Probability , Task Performance and Analysis , Young Adult
17.
Prog Brain Res ; 240: 53-69, 2018.
Article in English | MEDLINE | ID: mdl-30390841

ABSTRACT

We investigated the relationship between participation in team ball sports and performance in two sustained spatiotemporal attention tasks-a position monitoring variant of the multiple object tracking (MOT) task and target identification in the rapid serial visual presentation (RSVP) task. Thirty participants were asked about the frequency of their participation in team ball sports and undertook both the MOT task and RSVP task. In the MOT task, participants viewed an array of eight discs as they moved unpredictably for 3-8s before disappearing. On each trial, a subset of these were marked as targets for tracking, meaning that participants attempted to keep track of their positions on the screen with as much precision as possible. At the end of each trial, participants reported the final perceived position of a queried target. In the RSVP task, a stream of letters was presented at the center of the screen and participants attempted to report either one or both of two target letters embedded in the stream. Participation in team ball sports was associated with superior performance in both tasks: in the MOT task, individuals reporting more time spent playing team ball sports on a weekly basis were able to report the positions of targets with greater precision, and in the RSVP task they reported targets more accurately. The current findings add to the literature of somewhat mixed findings regarding the extent to which participation in sports may be associated with superior visual attention abilities.


Subject(s)
Attention/physiology , Sports , Visual Perception/physiology , Adult , Female , Humans , Male , Reaction Time , Young Adult
18.
Neuropsychologia ; 121: 79-87, 2018 12.
Article in English | MEDLINE | ID: mdl-30412713

ABSTRACT

Light-flicker Ganzfeld (LFG) induces a lower to upper-alpha frequency shift. However, it is unclear how this neurophysiological response might relate to LFG-induced pseudo-hallucinatory phenomena. It is also unknown whether emotional states (e.g., fear) or traits associated with risk for psychosis (e.g., proneness to perceptual anomalies, ability to produce vivid mental imagery) affect such neurophysiological and/or perceptual responses to LFG. The present study investigated alpha sub-bands during LFG across several flicker frequencies, in relation to individual differences in propensity for Ganzfeld-induced imagery (GI), positive schizotypy and trait mental imagery, and in relation to manipulations of affective state. Given previously reported sex differences in risk for psychosis and response to Ganzfeld, the effect of sex on GI was also studied. Forty-six healthy adults (16 men) completed psychometric measures of trait mental imagery and positive schizotypy before undergoing three LFG (20 min each) conditions. In each condition, participants wore white-out goggles and listened to either mood-inducing soundscapes (fear, serenity) or pink noise (control) through headphones. Greatest propensity for GI arose between 13.1 and 16.0 Hz flicker, with a peak at 16.0 Hz flicker. Occipital lower-alpha was reduced for lower flicker frequencies (13.1-16.0 Hz) and was inversely associated with GI. Upper-alpha power was not significantly related to GI or to other measures. Fear-induction was associated with reduction in alpha power, but did not significantly affect GI. Men reported more GI than women. Findings support a role for cortical destabilisation, as reflected in reduced lower-alpha, in perceptual anomalies; and, by extension, LFG as an experimental model of liability for psychosis.


Subject(s)
Alpha Rhythm/physiology , Brain/physiopathology , Hallucinations/physiopathology , Personality/physiology , Schizotypal Personality Disorder/physiopathology , Visual Perception/physiology , Adolescent , Adult , Affect/physiology , Fear/physiology , Female , Hallucinations/etiology , Hallucinations/psychology , Humans , Imagination/physiology , Male , Middle Aged , Photic Stimulation/methods , Sex Characteristics , Young Adult
19.
J Burn Care Res ; 39(6): 1017-1021, 2018 10 23.
Article in English | MEDLINE | ID: mdl-29931223

ABSTRACT

Acute kidney injury (AKI) after severe burns is historically associated with a high mortality. Over the past two decades, various modes of renal replacement therapy (RRT) have been used in this population. The purpose of this multicenter study was to evaluate demographic, treatment, and outcomes data among severe burn patients treated with RRT collectively at various burn centers around the United States. After institutional review board approval, a multicenter observational study was conducted. All adult patients aged 18 or older, admitted with severe burns who were placed on RRT for acute indications but not randomized into a concurrently enrolling interventional trial, were included. Across eight participating burn centers, 171 subjects were enrolled during a 4-year period. Complete data were available in 170 subjects with a mean age of 51 ± 17, percent total body surface area burn of 38 ± 26% and injury severity score of 27 ± 21. Eighty percent of subjects were male and 34% were diagnosed with smoke inhalation injury. The preferred mode of therapy was continuous venovenous hemofiltration at a mean delivered dose of 37 ± 19 (ml/kg/hour) and a treatment duration of 13 ± 24 days. Overall, in hospital, mortality was 50%. Among survivors, 21% required RRT on discharge from the hospital while 9% continued to require RRT 6 months after discharge. This is the first multicenter cohort of burn patients who underwent RRT reported to date. Overall mortality is comparable to other critically ill populations who undergo RRT. Most patients who survive to discharge eventually recover renal function.


Subject(s)
Acute Kidney Injury/etiology , Acute Kidney Injury/therapy , Burns/complications , Renal Replacement Therapy , Female , Humans , Male , Middle Aged , United States
20.
Exp Brain Res ; 236(5): 1445-1460, 2018 05.
Article in English | MEDLINE | ID: mdl-29546652

ABSTRACT

The position monitoring task is a measure of divided spatial attention in which participants track the changing positions of one or more objects, attempting to represent positions with as much precision as possible. Typically precision of representations declines with each target object added to participants' attention load. Since the motor system requires precise representations of changing target positions, we investigated whether position monitoring would be facilitated by increasing engagement of the motor system. Using motion capture, we recorded the positions of participants' index finger during pointing responses. Participants attempted to monitor the changing positions of between one and four target discs as they moved randomly around a large projected display. After a period of disc motion, all discs disappeared and participants were prompted to report the final position of one of the targets, either by mouse click or by pointing to the final perceived position on the screen. For mouse click responses, precision declined with attentional load. For pointing responses, precision declined only up to three targets and remained at the same level for four targets, suggesting obligatory attention to all four objects for loads above two targets. Kinematic profiles for pointing responses for highest and lowest loads showed greater motor adjustments during the point, demonstrating that, like external environmental task demands, the quality of internal representations affects motor kinematics. Specifically, these adjustments reflect the difficulty of both pointing to very precisely represented locations as well as keeping representations distinct from one another.


Subject(s)
Attention/physiology , Motion Perception/physiology , Psychomotor Performance/physiology , Adolescent , Adult , Biomechanical Phenomena/physiology , Female , Fingers , Humans , Male , Photic Stimulation , Young Adult
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