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Thulani H. Palpagama, Henry J. Waldvogel, Richard L. M. Faull et al. · 2019 · Frontiers in Molecular Neuroscience
Huntington's disease (HD) is an autosomal dominant neurodegenerative disease. HD patients present with movement disorders, behavioral and psychiatric symptoms and cognitive decline. This review summarizes the contribution of microglia and astrocytes to HD pathophysiology. Neuroinflammation in the HD brain is characterized by a reactive morphology in these glial cells. Microglia and astrocytes are critical in regulating neuronal activity and maintaining an optimal milieu for neuronal function. Previous studies provide evidence that activated microglia and reactive astrocytes contribute to HD pa
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Sarah J. Short, Tobias Stalder, Kristine Marceau et al. · 2016 · Psychoneuroendocrinology
Characterization of cortisol production, regulation and function is of considerable interest and relevance given its ubiquitous role in virtually all aspects of physiology, health and disease risk. The quantification of cortisol concentration in hair has been proposed as a promising approach for the retrospective assessment of integrated, long-term cortisol production. However, human research is still needed to directly test and validate current assumptions about which aspects of cortisol production and regulation are reflected in hair cortisol concentrations (HCC). Here, we report findings fr
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Conceição Bettencourt, Davina J. Hensman Moss, Michael Flower et al. · 2016 · Annals of Neurology
OBJECTIVE: The polyglutamine diseases, including Huntington's disease (HD) and multiple spinocerebellar ataxias (SCAs), are among the commonest hereditary neurodegenerative diseases. They are caused by expanded CAG tracts, encoding glutamine, in different genes. Longer CAG repeat tracts are associated with earlier ages at onset, but this does not account for all of the difference, and the existence of additional genetic modifying factors has been suggested in these diseases. A recent genome-wide association study (GWAS) in HD found association between age at onset and genetic variants in DNA r
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MaryAnn P. Noonan, Nika Adamian, Alexandra C. Pike et al. · 2016 · Journal of Neuroscience
It is well established that preparatory attention improves processing of task-relevant stimuli. Although it is often more important to ignore task-irrelevant stimuli, comparatively little is known about preparatory attentional mechanisms…
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Mi-Yeon Cho, Eun Sil Min, Myung‐Haeng Hur et al. · 2013 · Evidence-based Complementary and Alternative Medicine
The purpose of this study was to investigate the effects of aromatherapy on the anxiety, sleep, and blood pressure (BP) of percutaneous coronary intervention (PCI) patients in an intensive care unit (ICU). Fifty-six patients with PCI in ICU were evenly allocated to either the aromatherapy or conventional nursing care. Aromatherapy essential oils were blended with lavender, roman chamomile, and neroli with a 6 : 2 : 0.5 ratio. Participants received 10 times treatment before PCI, and the same essential oils were inhaled another 10 times after PCI. Outcome measures patients' state anxiety, sleepi
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Aaron T. Piepmeier, Jennifer L. Etnier · 2014 · Journal of sport and health science/Journal of Sport and Health Science
The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and…
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Megan A. K. Peters, Hakwan Lau · 2015 · eLife
Many believe that humans can 'perceive unconsciously' - that for weak stimuli, briefly presented and masked, above-chance discrimination is possible without awareness. Interestingly, an online survey reveals that most experts in the field recognize the lack of convincing evidence for this phenomenon, and yet they persist in this belief. Using a recently developed bias-free experimental procedure for measuring subjective introspection (confidence), we found no evidence for unconscious perception; participants' behavior matched that of a Bayesian ideal observer, even though the stimuli were visu
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Long Sha, James V. Haxby, Hervé Abdi et al. · 2014 · Journal of Cognitive Neuroscience
Major theories for explaining the organization of semantic memory in the human brain are premised on the often-observed dichotomous dissociation between living and nonliving objects. Evidence from neuroimaging has been interpreted to…
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Brandon J. Farley, Michael C. Quirk, James Doherty et al. · 2010 · Journal of Neuroscience
The significance of the mismatch negativity (MMN), an event-related potential measured in humans which indexes novelty in the auditory environment, has motivated a search for a cellular correlate of this process. A leading candidate is…
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Karl Nordström, Markus Sällman Almén, Monika M. Edstam et al. · 2011 · Molecular Biology and Evolution
Several families of G protein-coupled receptors (GPCRs) show no significant sequence similarities to each other, and it has been debated which of them share a common origin. We developed and performed integrated and independent HHsearch,…
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Ryan K. Shahidehpour, Rebecca E. Higdon, Nicole G. Crawford et al. · 2021 · Neurobiology of Aging
Loss of physiological microglial function may increase the propagation of neurodegenerative diseases. Cellular senescence is a hallmark of aging; thus, we hypothesized age could be a cause of dystrophic microglia. Stereological counts were…
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Weiwei Zhang, Steven J. Luck · 2011 · Psychological Science
Flexible-resource theories characterize working memory as a flexible resource that can store either a large number of low-quality representations or a small number of high-quality representations. In contrast, limited-item theories propose…
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Sean P. Burns, Dajun Xing, Robert Shapley · 2011 · Journal of Neuroscience
Gamma-band (25-90 Hz) peaks in local field potential (LFP) power spectra are present throughout the cerebral cortex and have been related to perception, attention, memory, and disorders (e.g., schizophrenia and autism). It has been…
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Ali Jannati, John M. Gaspar, John J. McDonald · 2013 · Journal of Experimental Psychology Human Perception & Performance
Salient distractors delay visual search for less salient targets in additional-singleton tasks, even when the features of the stimuli are fixed across trials. According to the salience-driven selection hypothesis, this delay is due to an…
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Dave R.M. Langers, Emile de Kleine, Pim van Dijk · 2012 · Frontiers in Systems Neuroscience
The pathophysiology underlying tinnitus, a hearing disorder characterized by the chronic perception of phantom sound, has been related to aberrant plastic reorganization of the central auditory system. More specifically, tinnitus is thought to involve changes in the tonotopic representation of sound. In the present study we used high-resolution functional magnetic resonance imaging to determine tonotopic maps in the auditory cortex of 20 patients with tinnitus but otherwise near-normal hearing, and compared these to equivalent outcomes from 20 healthy controls with matched hearing thresholds.
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Samuel J. Gershman, Edward Vul, Joshua B. Tenenbaum · 2011 · Neural Computation
Ambiguous images present a challenge to the visual system: How can uncertainty about the causes of visual inputs be represented when there are multiple equally plausible causes? A Bayesian ideal observer should represent uncertainty in the…
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Dongshan Yang, Chuan-En Wang, Bentian Zhao et al. · 2010 · Human Molecular Genetics
Neurodegeneration is a hallmark of many neurological diseases, including Alzheimer's, Parkinson's and the polyglutamine diseases, which are all caused by misfolded proteins that accumulate in neuronal cells of the brain. Although apoptosis…
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Christopher Summerfield, Valentin Wyart, Vanessa M. Johnen et al. · 2011 · Frontiers in Human Neuroscience
Repetitions of a sensory event elicit lower levels of brain activity than its initial presentation ("repetition suppression," RS). According to one view, RS depends on the biophysics of neuronal discharge, and is thus an automatic consequence of stimulus processing ("fatigue" model). Another account suggests that RS depends on the statistical structure of the environment, and occurs when repeated stimuli are less surprising than novel stimuli ("surprise reduction" model). In support of the latter view, functional magnetic resonance imaging studies have shown that RS is modulated by the local p
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Stephen B. R. E. Brown, Henk van Steenbergen, Guido P. H. Band et al. · 2012 · Frontiers in Human Neuroscience
The late positive potential (LPP) is an event-related potential (ERP) component over visual cortical areas that is modulated by the emotional intensity of a stimulus. However, the functional significance of this neural modulation remains elusive. We conducted two experiments in which we studied the relation between LPP amplitude, subsequent perceptual sensitivity to a non-emotional stimulus (Experiment 1) and visual cortical excitability, as reflected by P1/N1 components evoked by this stimulus (Experiment 2). During the LPP modulation elicited by unpleasant stimuli, perceptual sensitivity was
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Matthew J. Hollocks, Catherine R. G. Jones, Andrew Pickles et al. · 2014 · Autism Research
While high levels of anxiety and depression are now recognized as major co-occurring problems in children and young people with an autism spectrum disorder (ASD), research examining possible associations with individual differences in…
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Jack D. Wang, El‐Sayed Khafagy, Khalil Khanafer et al. · 2016 · Molecular Pharmaceutics
The endothelial cells lining the capillaries supplying the brain with oxygen and nutrients form a formidable barrier known as the blood-brain barrier (BBB), which exhibits selective permeability to small drug molecules and virtually…
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Stefan L. Frank · 2013 · Topics in Cognitive Science
The entropy-reduction hypothesis claims that the cognitive processing difficulty on a word in sentence context is determined by the word's effect on the uncertainty about the sentence. Here, this hypothesis is tested more thoroughly than…
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U. Müller, James B. Rowe, Timothy Rittman et al. · 2012 · Neuropharmacology
BACKGROUND: Modafinil, a putative cognitive enhancing drug, has previously been shown to improve performance of healthy volunteers as well as patients with attention deficit disorder and schizophrenia, mainly in tests of executive functions. The aim of this study was to investigate the effects of modafinil on non-verbal cognitive functions in healthy volunteers, with a particular focus on variations of cognitive load, measures of motivational factors and the effects on creative problem-solving. METHODS: A double-blind placebo-controlled parallel design study evaluated the effect of 200 mg of m
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Sutao Song, Zhichao Zhan, Zhiying Long et al. · 2011 · PLoS ONE
BACKGROUND: Support vector machine (SVM) has been widely used as accurate and reliable method to decipher brain patterns from functional MRI (fMRI) data. Previous studies have not found a clear benefit for non-linear (polynomial kernel) SVM versus linear one. Here, a more effective non-linear SVM using radial basis function (RBF) kernel is compared with linear SVM. Different from traditional studies which focused either merely on the evaluation of different types of SVM or the voxel selection methods, we aimed to investigate the overall performance of linear and RBF SVM for fMRI classification
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Vincent O. Nyasembe, Peter E. A. Teal, Wolfgang R Mukabana et al. · 2012 · Parasites & Vectors
BACKGROUND: Sugar feeding is critical for survival of malaria vectors and, although discriminative plant feeding previously has been shown to occur in Anopheles gambiae s.s., little is known about the cues mediating attraction to these plants. In this study, we investigated the role of olfaction in An. gambiae discriminative feeding behaviour. METHODS: Dual choice olfactometer assays were used to study odour discrimination by An. gambiae to three suspected host plants: Parthenium hysterophorus (Asteraceae), Bidens pilosa (Asteraceae) and Ricinus communis (Euphorbiaceae). Sugar content of the t
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Dana M. Brantley‐Sieders, Aixiang Jiang, Krishna Sarma et al. · 2011 · PLoS ONE
Pre-clinical studies provide compelling evidence that Eph family receptor tyrosine kinases (RTKs) and ligands promote cancer growth, neovascularization, invasion, and metastasis. Tumor suppressive roles have also been reported for the receptors, however, creating a potential barrier for clinical application. Determining how these observations relate to clinical outcome is a crucial step for translating the biological and mechanistic data into new molecularly targeted therapies. We investigated eph and ephrin expression in human breast cancer relative to endpoints of overall and/or recurrence-f
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Marian E. Berryhill · 2014 · Frontiers in Psychology
The popularity of non-invasive brain stimulation techniques in basic, commercial, and applied settings grew tremendously over the last decade. Here, we focus on one popular neurostimulation method: transcranial direct current stimulation (tDCS). Many assumptions regarding the outcomes of tDCS are based on the results of stimulating motor cortex. For instance, the primary motor cortex is predictably suppressed by cathodal tDCS or made more excitable by anodal tDCS. However, wide-ranging studies testing cognition provide more complex and sometimes paradoxical results that challenge this heuristi
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Selin Aviyente, Edward M. Bernat, Westley S. Evans et al. · 2010 · Human Brain Mapping
The temporal coordination of neural activity within structural networks of the brain has been posited as a basis for cognition. Changes in the frequency and similarity of oscillating electrical potentials emitted by neuronal populations…
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Min-Sun Kim, Yuan Yuan · 2015 · Episteme
Abstract In “Normativity and Epistemic Intuitions” (NEI), Weinberg, Nichols and Stich famously argue from empirical data that East Asians and Westerners have different intuitions about Gettier-style cases. We attempted to replicate their…
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Hans J. Grabe, Christian Schwahn, Katja Appel et al. · 2010 · American Journal of Medical Genetics Part B Neuropsychiatric Genetics
Dysregulations of the hypothalamic-pituitary-adrenal (HPA) axis have been implicated in the pathogenesis of depressive disorders and the corticotropin-releasing hormone (CRH) was found to modulate emotional memory consolidation. Recently,…
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