Read by QxMD icon Read

Brain Structure & Function

L Labache, M Joliot, J Saracco, G Jobard, I Hesling, L Zago, E Mellet, L Petit, F Crivello, B Mazoyer, Nathalie Tzourio-Mazoyer
We herein propose an atlas of 32 sentence-related areas based on a 3-step method combining the analysis of activation and asymmetry during multiple language tasks with hierarchical clustering of resting-state connectivity and graph analyses. 144 healthy right-handers performed fMRI runs based on language production, reading and listening, both with sentences and lists of over-learned words. Sentence minus word-list BOLD contrast and left-minus-right BOLD asymmetry for each task were computed in pairs of homotopic regions of interest (hROIs) from the AICHA atlas...
December 7, 2018: Brain Structure & Function
Yann Le Guen, Cathy Philippe, Denis Riviere, Hervé Lemaitre, Antoine Grigis, Clara Fischer, Ghislaine Dehaene-Lambertz, Jean-François Mangin, Vincent Frouin
The grey and white matter volumes are known to reduce with age. This cortical shrinkage is visible on magnetic resonance images and is conveniently identified by the increased volume of cerebrospinal fluid in the sulci between two gyri. Here, we replicated this finding using the UK Biobank dataset and studied the genetic influence on these cortical features of aging. We divided all individuals genetically confirmed of British ancestry into two sub-cohorts (12,162 and 3435 subjects for discovery and replication samples, respectively)...
December 5, 2018: Brain Structure & Function
Simone L Otto, Jerrel L Yakel
Disruption in cholinergic signaling has been linked to many environmental and/or pathological conditions known to modify adult neurogenesis. The α7 nAChRs are in the family of cys-loop receptor channels which have been shown to be neuroprotective in adult neurons and are thought to be critical for survival and integration of immature neurons. However, in developing neurons, poor calcium buffering may cause α7 nAChR activation to be neurotoxic. To investigate whether the α7 nAChR regulates neurogenesis in the hippocampus, we used a combination of mouse genetics and imaging to quantify neural stem cell (NSC) densities located in the dentate gyrus of adult mice...
December 4, 2018: Brain Structure & Function
James Fraser, Alexandra Essebier, Alexander S Brown, Raul Ayala Davila, Ameet S Sengar, YuShan Tu, Kathleen S Ensbey, Bryan W Day, Matthew P Scott, Richard M Gronostajski, Brandon J Wainwright, Mikael Boden, Tracey J Harvey, Michael Piper
Cerebellar granule neurons are the most numerous neuronal subtype in the central nervous system. Within the developing cerebellum, these neurons are derived from a population of progenitor cells found within the external granule layer of the cerebellar anlage, namely the cerebellar granule neuron precursors (GNPs). The timely proliferation and differentiation of these precursor cells, which, in rodents occurs predominantly in the postnatal period, is tightly controlled to ensure the normal morphogenesis of the cerebellum...
December 3, 2018: Brain Structure & Function
Byeong-Yeul Lee, Xiao-Hong Zhu, Xiufeng Li, Wei Chen
Characterization of the microstructural properties and topography of the human corpus callosum (CC) is key to understanding interhemispheric neural communication and brain function. In this work, we tested the hypothesis that high-resolution T1 relaxometry at high field has adequate sensitivity and specificity for characterizing microstructural properties of the human CC, and elucidating the structural connectivity of the callosal fibers to the cortices of origin. The high-resolution parametric T1 images acquired from healthy subjects (N = 16) at 7 T clearly showed a consistent T1 distribution among individuals with substantial variation along the human CC axis, which is highly similar to the spatial patterns of myelin density and myelinated axon size based on the histology study...
December 3, 2018: Brain Structure & Function
Annika Herten, Kerstin Konrad, Helga Krinzinger, Jochen Seitz, Georg G von Polier
The hippocampus (Hc) is of great importance in various psychiatric diseases in adults, children and adolescents. Automated Hc segmentation has been widely used in adults, implying sufficient overlap with manual segmentation. However, estimation biases related to the Hc volume have been pointed out. This may particularly apply to children who show age-related Hc volume changes, thus, questioning the accuracy of automated Hc segmentation in this age group. The aim of this study was to compare manual segmentation with automated segmentation using the widely adopted FreeSurfer (FS) and MAGeT-Brain software...
December 3, 2018: Brain Structure & Function
Benjamin Kreifelts, Lena Weigel, Thomas Ethofer, Carolin Brück, Michael Erb, Dirk Wildgruber
Social anxiety (SA) comprises a multitude of persistent fears around the central element of dreaded negative evaluation and exclusion. This very common anxiety is spectrally distributed among the general population and associated with social perception biases deemed causal in its maintenance. Here, we investigated cerebral resting state markers linking SA and biased social perception. To this end, resting state functional connectivity (RSFC) was assessed as the neurobiological marker in a study population with greatly varying SA using fMRI in the first step of the experiment...
December 1, 2018: Brain Structure & Function
Verónica Nácher, Seyed Alireza Hassani, Thilo Womelsdorf
The dorsal anterior cingulate cortex (dACC) and lateral prefrontal cortex (lPFC) of the non-human primate show neural firing correlations and synchronize at theta and beta frequencies during the monitoring and shifting of attention. These functional interactions might be based on synaptic connectivity that is equally efficacious in both directions, but it might be that there are systematic asymmetries in connectivity consistent with reports of more effective inhibition within the dACC than lPFC, or with a preponderance of dACC projections synapsing onto inhibitory neurons in the lPFC...
December 1, 2018: Brain Structure & Function
Emmanuelle Courtiol, Michelle Neiman, Gloria Fleming, Catia M Teixeira, Donald A Wilson
A growing body of evidence shows that olfactory information is processed within a thalamic nucleus in both rodents and humans. The mediodorsal thalamic nucleus (MDT) receives projections from olfactory cortical areas including the piriform cortex (PCX) and is interconnected with the orbitofrontal cortex (OFC). Using electrophysiology in freely moving rats, we recently demonstrated the representation of olfactory information in the MDT and the dynamics of functional connectivity between the PCX, MDT and OFC...
December 1, 2018: Brain Structure & Function
B M Siemsen, G Giannotti, J A McFaddin, M D Scofield, Jacqueline F McGinty
Cocaine self-administration (SA) in rats dysregulates glutamatergic signaling in the prelimbic (PrL) cortex and glutamate release in the nucleus accumbens (NA) core, promoting cocaine seeking. PrL adaptations that affect relapse to drug seeking emerge during the first week of abstinence, switching from an early (2 h) hypoglutamatergic state to a later (7 days) hyperglutamatergic state. Different interventions that normalize glutamatergic signaling in PrL cortex at each timepoint are necessary to suppress relapse...
November 29, 2018: Brain Structure & Function
Kylie H Alm, Chi T Ngo, Ingrid R Olson
Dominant theories of episodic memory propose that a key mechanism of memory consolidation is replay-a process, whereby neural patterns of activation during learning are reinstated during offline post-learning periods. Here, we tested whether key signatures of replay defined by studies in rodents, such as recapitulation of specific memory traces, as well as sequences, are apparent in humans during post-encoding memory reactivation. Thirty participants underwent functional imaging that consisted of interleaved encoding and rest periods...
November 26, 2018: Brain Structure & Function
Shotaro Otsuka, Harutoshi Sakakima, Takuto Terashi, Seiya Takada, Kazuki Nakanishi, Kiyoshi Kikuchi
14-3-3γ is an important early ischemia-inducible protective factor against ischemic cell death in cerebral cortical neurons. We investigated the anti-apoptosis mechanism of enhanced 14-3-3γ mediated by preconditioning exercise-induced brain ischemic tolerance after stroke. Rats were assigned to four groups: exercise and ischemia (Ex group), ischemia and no exercise (No-Ex group), exercise and no ischemia (Ex-only group), and no exercise and ischemia (control group). Rats were trained on a treadmill for 5 days a week for 3 weeks (running speed, 25 m/min; running duration, 30 min/day)...
November 26, 2018: Brain Structure & Function
Suhas Vijayakumar, Jerome Sallet, Lennart Verhagen, Davide Folloni, W Pieter Medendorp, Rogier B Mars
Resting state functional connectivity has been promoted as a promising tool for creating cortical maps that show remarkable similarity to those established by invasive histological methods. While this tool has been largely used to identify and map cortical areas, its true potential in the context of studying connectional architecture and in conducting comparative neuroscience has remained unexplored. Here, we employ widely used resting state connectivity and data-driven clustering methods to extend this approach for the study of the organizational principles of the macaque parietal-frontal system...
November 23, 2018: Brain Structure & Function
B Truchet, A Benoit, F Chaillan, P F Smith, B Philoxene, M Guillamin, B Poucet, A Coquerel, Stephane Besnard
Vestibular dysfunction strongly impairs hippocampus-dependent spatial memory performance and place cell function. However, the hippocampal encoding of vestibular information at the synaptic level, remains sparsely explored and controversial. We investigated changes in in vivo long-term potentiation (LTP) and NMDA glutamate receptor (NMDAr) density and distribution after bilateral vestibular lesions (BVL) in adult rats. At day 30 (D30 ) post-BVL, the LTP of the population spike recorded in the dentate gyrus (DG) was higher in BVL rats, for the entire 3 h of LTP recording, while no difference was observed in the fEPSP slope...
November 23, 2018: Brain Structure & Function
Arancha Botella-López, Raquel Garcia-Lopez, Ana Pombero, Salvador Martinez
Thalamic neurons are distributed between different nuclear groups of the thalamic multinuclear complex; they develop topologically ordered specific projections that convey information on voluntary motor programs and sensory modalities to functional areas in the cerebral cortex. Since thalamic neurons present a homogeneous morphology, their functional specificity is derived from their afferent and efferent connectivity. Adequate development of thalamic afferent and efferent connections depends on guide signals that bind receptors in nuclear neuropils and axonal growth cones, respectively...
November 23, 2018: Brain Structure & Function
Travis E Hodges, Emma L Louth, Craig D C Bailey, Cheryl M McCormick
Much evidence indicates that experiences in adolescence can alter the development of social behaviour. We previously demonstrated that male rats exposed to social instability stress in adolescence (SS; 1 h isolation and return to an unfamiliar cagemate daily from postnatal day [PND] 30-45) had reduced social interaction, impaired social recognition, reduced sexual performance, and increased aggression in competition for food reward compared with non-stressed control (CTL) rats. Here, we investigated whether SS affects stellate neuron morphology using the Golgi-Cox method and several markers of synaptic plasticity using western blotting in the medial amygdala (MeA) and lateral septum (LS), sites involved in social behaviour...
November 23, 2018: Brain Structure & Function
Prajwal Ghimire, Nurit Bedussa, Anastasios Giamouriadis, Christian Brogna, Noemia Pereira, Henrietta Howells, Ranj Bhangoo, Keyoumars Ashkan, Francesco Vergani
This study aimed at describing the first case of subcortical stimulation of the corticospinal tract leading to selective contraction of the intercostal muscles during surgery for removal of a tumour centred in the right central lobule/supplementary motor area. A 53-year-old male presented with partial motor seizures. Imaging demonstrated a low-grade glioma affecting the posterior aspect of the superior and middle frontal gyri and invading the precentral gyrus. Preoperative motor Transcranial Magnetic Stimulation and advanced diffusion tractography were performed to establish the relationship of the tumour with the motor cortex and corticospinal tract...
November 20, 2018: Brain Structure & Function
Rahul C Bhoyar, Arun G Jadhao, Ankit Sabharwal, Gyan Ranjan, Sridhar Sivasubbu, Claudia Pinelli
The present study initiates our investigation regarding the role of calb2a and calb2b genes that are expressed in the central nervous system, including the multiple tissues during early embryonic development of zebrafish. In this study, we have adopted individual and combined morpholino-mediated inactivation approach to investigate the functions of calb2a and calb2b in early development of the zebrafish. We have found that calb2a and calb2b morpholino alone failed to generate an obvious phenotype; however, morphological inspection in early developmental stages of calb2a and calb2b combined knockdown morphants show abnormal neural plate folding in midbrain-hindbrain region...
November 20, 2018: Brain Structure & Function
Chun-Wai Ma, Pui-Yi Kwan, Kenneth Lap-Kei Wu, Daisy Kwok-Yan Shum, Ying-Shing Chan
Perineuronal nets (PN) restrict neuronal plasticity in the adult brain. We hypothesize that activity-dependent consolidation of PN is required for functional maturation of behavioral circuits. Using the postnatal maturation of brainstem vestibular nucleus (VN) circuits as a model system, we report a neonatal period in which consolidation of central vestibular circuitry for graviception is accompanied by activity-dependent consolidation of chondroitin sulfate (CS)-rich PN around GABAergic neurons in the VN. Postnatal onset of negative geotaxis was used as an indicator for functional maturation of vestibular circuits...
November 20, 2018: Brain Structure & Function
Quentin Chenot, Nathalie Tzourio-Mazoyer, François Rheault, Maxime Descoteaux, Fabrice Crivello, Laure Zago, Emmanuel Mellet, Gaël Jobard, Marc Joliot, Bernard Mazoyer, Laurent Petit
With the advances in diffusion MRI and tractography, numerous atlases of the human pyramidal tract (PyT) have been proposed, but the inherent limitation of tractography to resolve crossing bundles within the centrum semiovale has so far prevented the complete description of the most lateral PyT projections. Here, we combined a precise manual positioning of individual subcortical regions of interest along the descending pathway of the PyT with a new bundle-specific tractography algorithm. This later is based on anatomical priors to improve streamlines tracking in crossing areas...
November 20, 2018: Brain Structure & Function
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"