Nigrostriatal Dopamine Acting on Globus Pallidus Regulates Sleep
Lesions of the globus pallidus externa (GPe) produce a profound sleep loss (~45%) in rats, suggesting that GPe neurons promote sleep. As GPe neuronal activity is enhanced by dopamine (DA) from the substantia nigra pars compacta (SNc), we hypothesized that SNc DA via the GPe promotes sleep. To test this hypothesis, we selectively destroyed the DA afferents to the caudoputamen (CPu) using 6-hydroxydopamine and examined changes in sleep-wake profiles in rats. Rats with 80–90% loss of SNc neurons displayed a significant 33.7% increase in wakefulness (or sleep reduction). This increase significantly correlated with the ex...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Qiu, M.-H., Yao, Q.-L., Vetrivelan, R., Chen, M. C., Lu, J. Tags: Original Articles Source Type: research
Opposite Neural Trajectories of Apolipoprotein E {epsilon}4 and {epsilon}2 Alleles with Aging Associated with Different Risks of Alzheimer's Disease
The apolipoprotein E (APOE) 4 allele is a confirmed genetic risk factor and the APOE 2 allele is a protective factor related to late-onset Alzheimer's disease (AD). Intriguingly, recent studies demonstrated similar brain function alterations between APOE 2 and 4 alleles, despite their opposite susceptibilities to AD. To address this apparent discrepancy, we recruited 129 cognitively normal elderly subjects, including 36 2 carriers, 44 3 homozygotes, and 49 4 carriers. All subjects underwent resting-state functional MRI scans. We hypothesized that aging could influence the APOE 2 and 4 allele effects that contribute to thei...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Shu, H., Shi, Y., Chen, G., Wang, Z., Liu, D., Yue, C., Ward, B. D., Li, W., Xu, Z., Chen, G., Guo, Q., Xu, J., Li, S.-J., Zhang, Z. Tags: Original Articles Source Type: research
The Role of Corticostriatal Systems in Speech Category Learning
One of the most difficult category learning problems for humans is learning nonnative speech categories. While feedback-based category training can enhance speech learning, the mechanisms underlying these benefits are unclear. In this functional magnetic resonance imaging study, we investigated neural and computational mechanisms underlying feedback-dependent speech category learning in adults. Positive feedback activated a large corticostriatal network including the dorsolateral prefrontal cortex, inferior parietal lobule, middle temporal gyrus, caudate, putamen, and the ventral striatum. Successful learning was contingen...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Yi, H.-G., Maddox, W. T., Mumford, J. A., Chandrasekaran, B. Tags: Original Articles Source Type: research
Prior Knowledge about Objects Determines Neural Color Representation in Human Visual Cortex
To create subjective experience, our brain must translate physical stimulus input by incorporating prior knowledge and expectations. For example, we perceive color and not wavelength information, and this in part depends on our past experience with colored objects ( Hansen et al. 2006; Mitterer and de Ruiter 2008). Here, we investigated the influence of object knowledge on the neural substrates underlying subjective color vision. In a functional magnetic resonance imaging experiment, human subjects viewed a color that lay midway between red and green (ambiguous with respect to its distance from red and green) presented o...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Vandenbroucke, A. R. E., Fahrenfort, J. J., Meuwese, J. D. I., Scholte, H. S., Lamme, V. A. F. Tags: Original Articles Source Type: research
Multiple Brain Markers are Linked to Age-Related Variation in Cognition
We examined multiple brain markers associated with age-related variation in cognition. Clinically normal older humans aged 65–90 from the Harvard Aging Brain Study (N = 186) were characterized on a priori magnetic resonance imaging markers of gray matter thickness and volume, white matter hyperintensities, fractional anisotropy (FA), resting-state functional connectivity, positron emission tomography markers of glucose metabolism and amyloid burden, and cognitive factors of processing speed, executive function, and episodic memory. Partial correlation and mediation analyses estimated age-related variance in cognition...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Hedden, T., Schultz, A. P., Rieckmann, A., Mormino, E. C., Johnson, K. A., Sperling, R. A., Buckner, R. L. Tags: Original Articles Source Type: research
Spatiotemporal Signatures of Lexical-Semantic Prediction
Although there is broad agreement that top-down expectations can facilitate lexical–semantic processing, the mechanisms driving these effects are still unclear. In particular, while previous electroencephalography (EEG) research has demonstrated a reduction in the N400 response to words in a supportive context, it is often challenging to dissociate facilitation due to bottom-up spreading activation from facilitation due to top-down expectations. The goal of the current study was to specifically determine the cortical areas associated with facilitation due to top-down prediction, using magnetoencephalography (MEG) rec...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Lau, E. F., Weber, K., Gramfort, A., Hamalainen, M. S., Kuperberg, G. R. Tags: Original Articles Source Type: research
Synaptic Basis for Cross-modal Plasticity: Enhanced Supragranular Dendritic Spine Density in Anterior Ectosylvian Auditory Cortex of the Early Deaf Cat
In the cat, the auditory field of the anterior ectosylvian sulcus (FAES) is sensitive to auditory cues and its deactivation leads to orienting deficits toward acoustic, but not visual, stimuli. However, in early deaf cats, FAES activity shifts to the visual modality and its deactivation blocks orienting toward visual stimuli. Thus, as in other auditory cortices, hearing loss leads to cross-modal plasticity in the FAES. However, the synaptic basis for cross-modal plasticity is unknown. Therefore, the present study examined the effect of early deafness on the density, distribution, and size of dendritic spines in the FAES. Y...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Clemo, H. R., Lomber, S. G., Meredith, M. A. Tags: Original Articles Source Type: research
{beta}-Adrenergic Control of Hippocampal Function: Subserving the Choreography of Synaptic Information Storage and Memory
Noradrenaline (NA) is a key neuromodulator for the regulation of behavioral state and cognition. It supports learning by increasing arousal and vigilance, whereby new experiences are "earmarked" for encoding. Within the hippocampus, experience-dependent information storage occurs by means of synaptic plasticity. Furthermore, novel spatial, contextual, or associative learning drives changes in synaptic strength, reflected by the strengthening of long-term potentiation (LTP) or long-term depression (LTD). NA acting on β-adrenergic receptors (β-AR) is a key determinant as to whether new experiences result in persist...
Source: Cerebral Cortex - March 10, 2016 Category: Neurology Authors: Hagena, H., Hansen, N., Manahan-Vaughan, D. Tags: Feature Article Source Type: research
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Source: Cerebral Cortex - March 10, 2016 Category: Neurology Tags: Cover/Standing Material Source Type: research
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Source: Cerebral Cortex - February 6, 2016 Category: Neurology Tags: Cover/Standing Material Source Type: research
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(Source: Cerebral Cortex)
Source: Cerebral Cortex - February 6, 2016 Category: Neurology Tags: Cover/Standing Material Source Type: research
Editorial Board
(Source: Cerebral Cortex)
Source: Cerebral Cortex - February 6, 2016 Category: Neurology Tags: Cover/Standing Material Source Type: research
