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1.
J Cogn Neurosci ; : 1-14, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38820552

RESUMO

We experience the present as a continuous stream of information, but often experience the past in parcels of unique events or episodes. Decades of research have helped to articulate how we perform this event segmentation in the moment, as well as how events and their boundaries influence what we later remember. More recently, neuroscientific research has suggested that the hippocampus plays a role at critical moments during event formation alongside its established role in enabling subsequent recall. Here, we review and explore the relationship between event processing and recall with the perspective that it can be uniquely characterized by the contributions of the hippocampus and its interactions with the rest of the brain. Specifically, we highlight a growing number of empirical studies suggesting that the hippocampus is important for processing events that have just ended, bridging the gap between the prior and current event, and influencing the contents and trajectories of recalled information. We also catalogue and summarize the multifaceted sets of findings concerning how recall is influenced by event structure. Lastly, we discuss several exciting directions for future research and how our understanding of events might be enriched by characterizing them in terms of the operations of different regions of the brain.

2.
Psychon Bull Rev ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803231

RESUMO

Changes in context influence the way we form and structure memories. Yet, little is known about how qualitatively different types of context switches shape memory organization. The current experiments characterize how different features of context change influence the structure and organization of free recall. Participants completed a context switching paradigm in which we manipulated the rate of switches and prior experience with the contexts participants were switching between (repeated vs. novel). We measured free-recall performance and determined the extent to which participants organized items by the order in which they were encoded or the type of context with which they were originally presented. Across two experiments, we found and replicated that rapidly switching to novel, but not repeated contexts, impaired memory recall performance and biased memory towards a greater reliance on temporal information. Critically, we observed that these differences in performance may be due to distinctions in how participants organize their recalls when rapidly switching contexts. Results indicated that participants were less likely to only cluster their responses by the same context when the contexts were repeating at a high rate, as compared to when the contexts were novel. Overall, our findings support a model in which contextual familiarity rescues the costs associated with rapidly switching to new tasks or contexts.

3.
Psychiatry Res Neuroimaging ; 333: 111661, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37331318

RESUMO

Given the association between major depressive disorder (MDD) and cortical inefficiency related to executive control, specifically in the sense that individuals with MDD may recruit more cognitive resources to complete tasks at the same capacity as those without MDD, the current study was interested in examining the attention networks and executive functioning of those with MDD. Past research has used the Attention Network Test (ANT) to measure changes of attention in clinical vs. healthy populations; however, theoretical concerns have been raised regarding the task. The Combined Attention Systems Task (CAST) was developed to address these concerns and was used in our study in combination with quantitative-electroencephalography (QEEG) to assess both behavioural and neurophysiological changes in participants with MDD (n = 18) compared to healthy controls (HCs; n = 22). We found no behavioural differences between MDD and HC groups suggesting individuals with MDD in our sample were not experiencing the executive functioning deficits previously reported in the literature. Neurophysiological measures of attention revealed that MDD participants had greater theta and alpha1 activity relative to HCs, suggesting that although individuals with MDD do not show deficits in behavioural attention, they exhibit altered neural processing which underlies cognitive function.


Assuntos
Transtorno Depressivo Maior , Humanos , Depressão , Função Executiva/fisiologia , Cognição , Eletroencefalografia
4.
Microbiol Resour Announc ; 12(7): e0130422, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37338395

RESUMO

We report the metagenome sequences of two microbial cultures that were grown with chemically deconstructed plastic products as their sole carbon source. These metagenomes will provide insights into the metabolic capabilities of cultures grown on deconstructed plastics and can serve as a starting point for the identification of novel plastic degradation mechanisms.

5.
Microbiol Spectr ; 11(4): e0036223, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37260392

RESUMO

Over half of the world's plastic waste is landfilled, where it is estimated to take hundreds of years to degrade. Given the continued use and disposal of plastic products, it is vital that we develop fast and effective ways to utilize plastic waste. Here, we explore the potential of tandem chemical and biological processing to process various plastics quickly and effectively. Four samples of compost or sediment were used to set up enrichment cultures grown on mixtures of compounds, including disodium terephthalate and terephthalic acid (monomers of polyethylene terephthalate), compounds derived from the chemical deconstruction of polycarbonate, and pyrolysis oil derived from high-density polyethylene plastics. Established enrichment communities were also grown on individual substrates to investigate the substrate preferences of different taxa. Biomass harvested from the cultures was characterized using 16S rRNA gene amplicon sequencing and shotgun metagenomic sequencing. These data reveal low-diversity microbial communities structured by differences in culture inoculum, culture substrate source plastic type, and time. Microbial populations from the classes Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, and Acidobacteriae were significantly enriched when grown on substrates derived from high-density polyethylene and polycarbonate. The metagenomic data contain abundant aromatic and aliphatic hydrocarbon degradation genes relevant to the biodegradation of deconstructed plastic substrates used here. We show that microbial populations from diverse environments are capable of growth on substrates derived from the chemical deconstruction or pyrolysis of multiple plastic types and that paired chemical and biological processing of plastics should be further developed for industrial applications to manage plastic waste. IMPORTANCE The durability and impermeable nature of plastics have made them a popular material for numerous applications, but these same qualities make plastics difficult to dispose of, resulting in massive amounts of accumulated plastic waste in landfills and the natural environment. Since plastic use and disposal are projected to increase in the future, novel methods to effectively break down and dispose of current and future plastic waste are desperately needed. We show that the products of chemical deconstruction or pyrolysis of plastic can successfully sustain the growth of low-diversity microbial communities. These communities were enriched from multiple environmental sources and are capable of degrading complex xenobiotic carbon compounds. This study demonstrates that tandem chemical and biological processing can be used to degrade multiple types of plastics over a relatively short period of time and may be a future avenue for the mitigation of rapidly accumulating plastic waste.


Assuntos
Plásticos , Polietileno , Plásticos/metabolismo , Polietileno/metabolismo , RNA Ribossômico 16S/genética , Polietilenotereftalatos/metabolismo , Bactérias
6.
Exp Brain Res ; 241(5): 1319-1327, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37004533

RESUMO

Multiple sclerosis (MS) is one of the most common neurological diseases in North America and it is frequently associated with sensory processing difficulties, cognitive deficits, and psychiatric illness. While many studies have examined cognitive deficits in MS measured by behavioural responses and neuroimaging techniques, only a few studies have examined neurophysiological measures of auditory functioning in MS, such as the mismatch negativity (MMN). The MMN is an event-related potential that indicates automatic auditory change detection. This study examined whether MMN endpoints measured by electroencephalography (EEG) differ in individuals with relapsing-remitting MS compared to healthy controls and whether the symptomatology of MS, including symptoms of depression and fatigue, are related to MMN measures. A multi-feature MMN paradigm, which includes five distinct deviant tones, was used to assess auditory cortex function in MS. There were no significant differences in MMN amplitudes or latencies between the MS and control group (p < 0.05) and corresponding effect sizes were small. However, there was a correlation between reduced MMN amplitudes in response to an intensity deviant and physician-reported disability. The intensity MMN may be more sensitive to deterioration in this population. Ultimately, this study provides a comprehensive profile of early auditory processing abilities in MS and suggests that a reduction in the MMN response may be representative of disease severity in MS.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Estimulação Acústica/métodos , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Percepção Auditiva/fisiologia , Potenciais Evocados/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia
7.
Trends Biotechnol ; 41(2): 184-196, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36058768

RESUMO

Most polyethylene terephthalate (PET) plastic waste is landfilled or pollutes the environment. Additionally, global food production must increase to support the growing population. This article explores the feasibility of using microorganisms in an industrial system that upcycles PET into edible microbial protein powder to solve both problems simultaneously. Many microorganisms can utilize plastics as feedstock, and the resultant microbial biomass contains fats, nutrients, and proteins similar to those found in human diets. While microbial degradation of PET is promising, biological PET depolymerization is too slow to resolve the global plastic crisis and projected food shortages. Evidence reviewed here suggests that by coupling chemical depolymerization and biological degradation of PET, and using cooperative microbial communities, microbes can efficiently convert PET waste into food.


Assuntos
Microbiota , Plásticos , Humanos , Plásticos/química , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Alimentos , Biomassa
8.
Mult Scler Relat Disord ; 68: 104229, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36279599

RESUMO

BACKGROUND: Slowed processing speed is the most frequently reported cognitive deficit for people with multiple sclerosis (MS). However, measures used to assess processing speed may also recruit other cognitive abilities. The present objective was to determine the contributions of different cognitive functions to performance on two commonly used processing speed measures: the Symbol Digit Modalities Test (SDMT) and the Paced Auditory Serial Addition Test (PASAT). METHODS: Adults with relapsing-remitting MS (n = 70) and controls (n = 72) completed the SDMT, PASAT, and multiple measures assessing processing speed, working memory, and learning. Hierarchical regression analyses were used to examine the contributions of MS, processing speed, working memory, learning, and all possible interactions among factors to SDMT and PASAT scores. RESULTS: Processing speed and working memory generally contributed to performance on the SDMT and PASAT, with learning additionally contributing to SDMT performance. However, significant interactions revealed processing speed did not influence PASAT performance for individuals with high working memory ability whereas processing speed became increasingly more important as working memory declined to average and low levels. Further, processing speed was associated with SDMT performance for patients with MS but not controls. CONCLUSIONS: These findings support a multifactorial interpretation of the SDMT and PASAT, which facilitates their usefulness as screening measures for cognitive decline but prevents them from identifying which specific cognitive functions are affected.


Assuntos
Transtornos Cognitivos , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Adulto , Humanos , Velocidade de Processamento , Testes Neuropsicológicos , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Transtornos Cognitivos/diagnóstico , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico
9.
Front Cell Dev Biol ; 10: 854373, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433674

RESUMO

Epithelial tissues are vital to the function of most organs, providing critical functions such as secretion, protection, and absorption. Cells within an epithelial layer must coordinate to create functionally distinct apical, lateral, and basal surfaces in order to maintain proper organ function and organism viability. This is accomplished through the careful targeting of polarity factors to their respective locations within the cell, as well as the strategic placement of post-mitotic cells within the epithelium during tissue morphogenesis. The process of establishing and maintaining epithelial tissue integrity is conserved across many species, as important polarity factors and spindle orientation mechanisms can be found in many phyla. However, most of the information gathered about these processes and players has been investigated in bilaterian organisms such as C. elegans, Drosophila, and vertebrate species. This review discusses the advances made in the field of epithelial polarity establishment from more basal organisms, and the advantages to utilizing these simpler models. An increasing number of cnidarian model organisms have been sequenced in recent years, such as Hydra vulgaris and Nematostella vectensis. It is now feasible to investigate how polarity is established and maintained in basal organisms to gain an understanding of the most basal requirements for epithelial tissue morphogenesis.

10.
Life Sci Alliance ; 5(7)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35304423

RESUMO

The last stage of cell division involves two daughter cells remaining interconnected by a cytokinetic bridge that is cleaved during abscission. Conserved between the zebrafish embryo and human cells, we found that the oldest centrosome moves in a Rab11-dependent manner towards the cytokinetic bridge sometimes followed by the youngest. Rab11-endosomes are organized in a Rab11-GTP dependent manner at the mother centriole during pre-abscission, with Rab11 endosomes at the oldest centrosome being more mobile compared with the youngest. The GTPase activity of Rab11 is necessary for the centrosome protein, Pericentrin, to be enriched at the centrosome. Reduction in Pericentrin expression or optogenetic disruption of Rab11-endosome function inhibited both centrosome movement towards the cytokinetic bridge and abscission, resulting in daughter cells prone to being binucleated and/or having supernumerary centrosomes. These studies suggest that Rab11-endosomes contribute to centrosome function during pre-abscission by regulating Pericentrin organization resulting in appropriate centrosome movement towards the cytokinetic bridge and subsequent abscission.


Assuntos
Peixe-Zebra , Proteínas rab de Ligação ao GTP , Animais , Antígenos , Centrossomo/metabolismo , Endossomos/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
11.
mSystems ; 6(5): e0030021, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34519519

RESUMO

In recent years, our appreciation of the extent of habitable environments in Earth's subsurface has greatly expanded, as has our understanding of the biodiversity contained within. Most studies have relied on single sampling points, rather than considering the long-term dynamics of subsurface environments and their microbial populations. One such habitat are aquifers associated with the aqueous alteration of ultramafic rocks through a process known as serpentinization. Ecological modeling performed on a multiyear time series of microbiology, hydrology, and geochemistry in an ultrabasic aquifer within the Coast Range Ophiolite reveals that community assembly is governed by undominated assembly (i.e., neither stochastic [random] nor deterministic [selective] processes alone govern assembly). Controls on community assembly were further assessed by characterizing aquifer hydrogeology and microbial community adaptations to the environment. These analyses show that low permeability rocks in the aquifer restrict the transmission of microbial populations between closely situated wells. Alpha and beta diversity measures and metagenomic and metatranscriptomic data from microbial communities indicate that high pH and low dissolved inorganic carbon levels impose strong environmental selection on microbial communities within individual wells. Here, we find that the interaction between strong selection imposed by extreme pH and enhanced ecological drift due to dispersal limitation imposed by slow fluid flow results in the undominated assembly signal observed throughout the site. Strong environmental selection paired with extremely low dispersal in the subsurface results in low diversity microbial communities that are well adapted to extreme pH conditions and subject to enhanced stochasticity introduced by ecological drift over time. IMPORTANCE Microbial communities existing under extreme or stressful conditions have long been thought to be structured primarily by deterministic processes. The application of macroecology theory and modeling to microbial communities in recent years has spurred assessment of assembly processes in microbial communities, revealing that both stochastic and deterministic processes are at play to different extents within natural environments. We show that low diversity microbial communities in a hard-rock serpentinizing aquifer are assembled under the influence of strong selective processes imposed by high pH and enhanced ecological drift that occurs as the result of dispersal limitation due to the slow movement of water in the low permeability aquifer. This study demonstrates the important roles that both selection and dispersal limitation play in terrestrial serpentinites, where extreme pH assembles a microbial metacommunity well adapted to alkaline conditions and dispersal limitation drives compositional differences in microbial community composition between local communities in the subsurface.

12.
STAR Protoc ; 2(1): 100293, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33554134

RESUMO

During the earliest division stages, zebrafish embryos have large cells that divide rapidly and synchronously to create a cellular layer on top of the yolk. Here, we describe a protocol for monitoring spindle dynamics during these early embryonic divisions. We outline techniques for injecting zebrafish embryos with small-molecule inhibitors toward polo-like kinases, preparing and mounting embryos for three-dimensional imaging using confocal microscopy. These techniques are used to understand how the early zebrafish embryo's centrosome constructs the mitotic spindle. For complete details on the use and execution of this protocol, please refer to Rathbun et al. (2020).


Assuntos
Centrossomo/metabolismo , Embrião não Mamífero/embriologia , Mitose/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Fuso Acromático/metabolismo , Peixe-Zebra/embriologia , Animais , Microscopia Confocal
13.
Curr Biol ; 30(22): 4519-4527.e3, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-32916112

RESUMO

Factors that regulate mitotic spindle positioning remain unclear within the confines of extremely large embryonic cells, such as the early divisions of the vertebrate embryo, Danio rerio (zebrafish). We find that the mitotic centrosome, a structure that assembles the mitotic spindle [1], is notably large in the zebrafish embryo (246.44 ± 11.93 µm2 in a 126.86 ± 0.35 µm diameter cell) compared to a C. elegans embryo (5.78 ± 0.18 µm2 in a 55.83 ± 1.04 µm diameter cell). During embryonic cell divisions, cell size changes rapidly in both C. elegans and zebrafish [2, 3], where mitotic centrosome area scales more closely with changes in cell size compared to changes in spindle length. Embryonic zebrafish spindles contain asymmetrically sized mitotic centrosomes (2.14 ± 0.13-fold difference between the two), with the larger mitotic centrosome placed toward the embryo center in a polo-like kinase (PLK) 1- and PLK4-dependent manner. We propose a model in which uniquely large zebrafish embryonic centrosomes direct spindle placement within disproportionately large cells.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Centrossomo/metabolismo , Desenvolvimento Embrionário , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fuso Acromático/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Proteínas de Ciclo Celular/genética , Tamanho Celular , Embrião não Mamífero , Microscopia Intravital , Microscopia Confocal , Mitose , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Quinase 1 Polo-Like
14.
Clin EEG Neurosci ; 51(6): 365-372, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32345046

RESUMO

In major depressive disorder (MDD), event-related potentials that are involved in auditory cortex function (i.e. N100 and P300) often have greater latencies and decreased amplitudes. The auditory mismatch negativity (MMN) is thought to be produced by generators in the auditory cortex, as well as the frontal lobes. Reports on differences in MMN in those with MDD have been varied. It was hypothesized that the wide range of results in the literature may be due to the use of different deviant types in eliciting the MMN. To attempt and explain these inconsistencies, the current study employed a multifeature MMN paradigm with 5 deviant tone types in community-dwelling participants with a diagnosis of MDD. We found those with MDD had higher MMN amplitudes following tones that deviated in intensity and location, but no difference in MMNs elicted by the other deivants (relative to unaffected controls). Location MMN deviants were negatively correlated with depression severity scores (i.e. larger MMN with greater severity). We also found longer MMN latencies following the pitch deviant. These results suggest the early auditory change detection process is altered in MDD, but only following certain types of auditory stimuli. Potential explanations for these findings, including high levels of anxiety and the influence of tryptophan are explored. Equally, the current report highlights the importance of using various deviant types when examining the MMN in clinical populations.


Assuntos
Transtorno Depressivo Maior , Estimulação Acústica , Percepção Auditiva , Transtorno Depressivo Maior/diagnóstico , Eletroencefalografia , Potenciais Evocados Auditivos , Humanos
15.
Environ Microbiol ; 22(6): 2329-2345, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32249550

RESUMO

Serpentinization is the hydration and oxidation of ultramafic rock, which occurs as oceanic lithosphere is emplaced onto continental margins (ophiolites), and along the seafloor as faulting exposes this mantle-derived material to circulating hydrothermal fluids. This process leads to distinctive fluid chemistries as molecular hydrogen (H2 ) and hydroxyl ions (OH- ) are produced and reduced carbon compounds are mobilized. Serpentinizing ophiolites also serve as a vector to transport sulfur compounds from the seafloor onto the continents. We investigated hyperalkaline, sulfur-rich, brackish groundwater in a serpentinizing continental ophiolite to elucidate the role of sulfur compounds in fuelling in situ microbial activities. Here we illustrate that key sulfur-cycling taxa, including Dethiobacter, Desulfitispora and 'Desulforudis', persist throughout this extreme environment. Biologically catalysed redox reactions involving sulfate, sulfide and intermediate sulfur compounds are thermodynamically favourable in the groundwater, which indicates they may be vital to sustaining life in these characteristically oxidant- and energy-limited systems. Furthermore, metagenomic and metatranscriptomic analyses reveal a complex network involving sulfate reduction, sulfide oxidation and thiosulfate reactions. Our findings highlight the importance of the complete inorganic sulfur cycle in serpentinizing fluids and suggest sulfur biogeochemistry provides a key link between terrestrial serpentinizing ecosystems and their submarine heritage.


Assuntos
Fenômenos Geológicos , Compostos de Enxofre/metabolismo , Microbiologia da Água , Microbiota , Oxirredução , Enxofre
16.
mSystems ; 5(2)2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32156795

RESUMO

Serpentinization is a low-temperature metamorphic process by which ultramafic rock chemically reacts with water. Such reactions provide energy and materials that may be harnessed by chemosynthetic microbial communities at hydrothermal springs and in the subsurface. However, the biogeochemistry mediated by microbial populations that inhabit these environments is understudied and complicated by overlapping biotic and abiotic processes. We applied metagenomics, metatranscriptomics, and untargeted metabolomics techniques to environmental samples taken from the Coast Range Ophiolite Microbial Observatory (CROMO), a subsurface observatory consisting of 12 wells drilled into the ultramafic and serpentinite mélange of the Coast Range Ophiolite in California. Using a combination of DNA and RNA sequence data and mass spectrometry data, we found evidence for several carbon fixation and assimilation strategies, including the Calvin-Benson-Bassham cycle, the reverse tricarboxylic acid cycle, the reductive acetyl coenzyme A (acetyl-CoA) pathway, and methylotrophy, in the microbial communities inhabiting the serpentinite-hosted aquifer. Our data also suggest that the microbial inhabitants of CROMO use products of the serpentinization process, including methane and formate, as carbon sources in a hyperalkaline environment where dissolved inorganic carbon is unavailable.IMPORTANCE This study describes the potential metabolic pathways by which microbial communities in a serpentinite-influenced aquifer may produce biomass from the products of serpentinization. Serpentinization is a widespread geochemical process, taking place over large regions of the seafloor and at continental margins, where ancient seafloor has accreted onto the continents. Because of the difficulty in delineating abiotic and biotic processes in these environments, major questions remain related to microbial contributions to the carbon cycle and physiological adaptation to serpentinite habitats. This research explores multiple mechanisms of carbon fixation and assimilation in serpentinite-hosted microbial communities.

17.
J Cogn Neurosci ; 32(3): 527-545, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31820676

RESUMO

Recent work suggests that a key function of the hippocampus is to predict the future. This is thought to depend on its ability to bind inputs over time and space and to retrieve upcoming or missing inputs based on partial cues. In line with this, previous research has revealed prediction-related signals in the hippocampus for complex visual objects, such as fractals and abstract shapes. Implicit in such accounts is that these computations in the hippocampus reflect domain-general processes that apply across different types and modalities of stimuli. An alternative is that the hippocampus plays a more domain-specific role in predictive processing, with the type of stimuli being predicted determining its involvement. To investigate this, we compared hippocampal responses to auditory cues predicting abstract shapes (Experiment 1) versus oriented gratings (Experiment 2). We measured brain activity in male and female human participants using high-resolution fMRI, in combination with inverted encoding models to reconstruct shape and orientation information. Our results revealed that expectations about shape and orientation evoked distinct representations in the hippocampus. For complex shapes, the hippocampus represented which shape was expected, potentially serving as a source of top-down predictions. In contrast, for simple gratings, the hippocampus represented only unexpected orientations, more reminiscent of a prediction error. We discuss several potential explanations for this content-based dissociation in hippocampal function, concluding that the computational role of the hippocampus in predictive processing may depend on the nature and complexity of stimuli.


Assuntos
Percepção Auditiva/fisiologia , Sinais (Psicologia) , Hipocampo/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos , Adulto Jovem
18.
Neurology ; 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30635487

RESUMO

OBJECTIVE: To determine whether anxiety and depression are associated with cognition in multiple sclerosis (MS), and whether these associations are similar in other immune-mediated inflammatory diseases (IMID; including inflammatory bowel disease [IBD] and rheumatoid arthritis [RA]) and in anxious/depressed individuals (ANX/DEP) without an IMID. METHODS: Participants (MS: n = 255; IBD: n = 247; RA: n = 154; ANX/DEP: n = 308) completed a structured psychiatric interview, the Hospital Anxiety and Depression Scale, and cognitive testing, including the Symbol Digit Modalities Test, the California Verbal Learning Test, and Letter Number Sequencing test. Test scores were converted to age-, sex-, and education-adjusted z scores. We evaluated associations of anxiety and depression with the cognitive z scores using multivariate linear models, adjusting for disease cohort. RESULTS: All cohorts exhibited higher rates of impairment (i.e., z less than or equal to -1.5) in the domains of processing speed, verbal learning, and delayed recall memory relative to general population norms. Higher levels of anxiety symptoms were associated with slower processing speed, lower verbal learning, and lower working memory performance (all p < 0.001); higher levels of depression symptoms were associated with slower processing speed. These associations did not differ across cohorts. CONCLUSION: Anxiety and depression are associated with lower cognitive function in MS, with a similar pattern observed in persons with other IMID, including IBD and RA, and persons without an IMID. Managing symptoms of anxiety and of depression in MS, as well as other IMIDs, is important to mitigate their effect on cognition.

19.
Int J MS Care ; 20(2): 76-84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670493

RESUMO

BACKGROUND: Studies assessing the prevalence of depression and anxiety in multiple sclerosis (MS) have used various ascertainment methods that capture different constructs. The relationships between these methods are incompletely understood. Psychiatric comorbidity is associated with lower health-related quality of life (HRQOL) in MS, but the effects of past diagnoses of depression and anxiety on HRQOL are largely unknown. We compared the prevalence of depression and anxiety in persons with MS using administrative data, self-reported physician diagnoses, and symptom-based measures and compared characteristics of persons classified as depressed or anxious by each method. We evaluated whether HRQOL was most affected by previous diagnoses of depression or anxiety or by current symptoms. METHODS: We linked clinical and administrative data for 859 participants with MS. HRQOL was measured by the Health Utilities Index Mark 3. We classified participants as depressed or anxious using administrative data, self-reported physician diagnoses, and the Hospital Anxiety and Depression Scale. Multivariable linear regression examined whether diagnosed depression or anxiety affected HRQOL after accounting for current symptoms. RESULTS: Lifetime prevalence estimates for depression were approximately 30% regardless of methods used, but 35.8% with current depressive symptoms were not captured by either administrative data or self-reported diagnoses. Prevalence estimates of anxiety ranged from 11% to 19%, but 65.6% with current anxiety were not captured by either administrative data or self-reported diagnoses. Previous diagnoses did not decrease HRQOL after accounting for current symptoms. CONCLUSIONS: Depression and, to a greater extent, anxiety remain underdiagnosed and undertreated in MS; both substantially contribute to reduced HRQOL in MS.

20.
J Fish Biol ; 92(6): 1849-1865, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29603222

RESUMO

A total of 230 anadromous Salmo trutta (brown trout) were sampled in five sheltered coastal fjords (or sea lochs) on the Isle of Skye, Scotland, U.K., in 2016 at varying distances from active Atlantic salmon Salmo salar farms. Statistical models were developed to investigate potential correlations between salmon lice Lepeophtheirus salmonis burdens on S. trutta hosts and their proximity to S. salar farm cages. Significant correlations were found between lice burdens and fish fork length and proximity to the nearest S. salar farm. The probability of the presence of L. salmonis on fish hosts increased with fish host size and with distance from the nearest S. salar farm, but total lice burdens were highest in fish sampled near S. salar farms and decreased with distance. The proportion of different life-cycle stages of L. salmonis were also dependent on S. salar farm proximity, with higher juvenile lice numbers recorded at sites near S. salar farm cages. These results highlight the complexity of the relationship between S. trutta and L. salmonis infections on wild fish and emphasize the requirement of further research to quantify these effects to better inform conservation and management strategies, particularly in areas of active S. salar farm facilities.


Assuntos
Aquicultura , Copépodes , Doenças dos Peixes/transmissão , Salmo salar/parasitologia , Truta/parasitologia , Animais , Feminino , Doenças dos Peixes/parasitologia , Masculino , Escócia
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