scholarly journals Ultrasound Produces Extensive Brain Activation via a Cochlear Pathway

2017 ◽  
Author(s):  
Hongsun Guo ◽  
Mark Hamilton ◽  
Sarah J. Offutt ◽  
Cory D. Gloeckner ◽  
Tianqi Li ◽  
...  
Keyword(s):  
Underlying Mechanism ◽  
Brain Regions ◽  
Neural Activation ◽  
Auditory Pathways ◽  
Auditory Nerves ◽  
Brain Circuits ◽  
The Us ◽  
Intact Brain ◽  
Vibration Mechanism ◽  
The Brain

SummaryUltrasound (US) can noninvasively activate intact brain circuits, making it a promising neuromodulation technique. However, little is known about the underlying mechanism. Here, we apply transcranial US and perform brain mapping studies in guinea pigs using extracellular electrophysiology. We find that US elicits extensive activation across cortical and subcortical brain regions. However, transection of the auditory nerves or removal of cochlear fluids eliminates the US-induced activity, revealing an indirect auditory mechanism for US neural activation. US likely vibrates the cerebrospinal fluid in the brain, which is continuous with the fluid in the cochlea via cochlear aqueducts; thus, US can activate the ascending auditory pathways and other non-auditory regions through cross-modal projections. This finding of a cochlear fluid-induced vibration mechanism challenges the idea that US can directly activate neurons in the intact brain, suggesting that future US stimulation studies will need to control for this effect to reach reliable conclusions.

scholarly journals The Neural Basis of Shared Preference Learning

2019 ◽  
Author(s):  
Harry Farmer ◽  
Uri Hertz ◽  
Antonia Hamilton
Keyword(s):  
Social Interactions ◽  
Computational Modelling ◽  
Brain Regions ◽  
The Self ◽  
Neural Activation ◽  
Neural Basis ◽  
Daily Lives ◽  
Neural Processes ◽  
Specific Manner ◽  
The Brain

AbstractDuring our daily lives, we often learn about the similarity of the traits and preferences of others to our own and use that information during our social interactions. However, it is unclear how the brain represents similarity between the self and others. One possible mechanism is to track similarity to oneself regardless of the identity of the other (Similarity account); an alternative is to track each confederate in terms of consistency of the similarity to the self, with respect to the choices they have made before (consistency account). Our study combined fMRI and computational modelling of reinforcement learning (RL) to investigate the neural processes that underlie learning about preference similarity. Participants chose which of two pieces of artwork they preferred and saw the choices of one confederate who usually shared their preference and another who usually did not. We modelled neural activation with RL models based on the similarity and consistency accounts. Data showed more brain regions whose activity pattern fits with the consistency account, specifically, areas linked to reward and social cognition. Our findings suggest that impressions of other people can be calculated in a person-specific manner which assumes that each individual behaves consistently with their past choices.

scholarly journals Inter-individual differences in pain anticipation and pain perception in migraine: Neural correlates of migraine frequency and cortisol-to-dehydroepiandrosterone sulfate (DHEA-S) ratio

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261570
Author(s):  
Gyöngyi Kökönyei ◽  
Attila Galambos ◽  
Natália Kocsel ◽  
Edina Szabó ◽  
Andrea Edit Édes ◽  
...  
Keyword(s):  
Individual Differences ◽  
Allostatic Load ◽  
Pain Perception ◽  
Dehydroepiandrosterone Sulfate ◽  
Brain Regions ◽  
Episodic Migraine ◽  
Neural Activation ◽  
Migraine Frequency ◽  
Two Phases ◽  
The Brain

Previous studies targeting inter-individual differences in pain processing in migraine mainly focused on the perception of pain. Our main aim was to disentangle pain anticipation and perception using a classical fear conditioning task, and investigate how migraine frequency and pre-scan cortisol-to-dehydroepiandrosterone sulfate (DHEA-S) ratio as an index of neurobiological stress response would relate to neural activation in these two phases. Functional Magnetic Resonance Imaging (fMRI) data of 23 participants (18 females; mean age: 27.61± 5.36) with episodic migraine without aura were analysed. We found that migraine frequency was significantly associated with pain anticipation in brain regions comprising the midcingulate and caudate, whereas pre-scan cortisol-to DHEA-S ratio was related to pain perception in the pre-supplementary motor area (pre-SMA). Both results suggest exaggerated preparatory responses to pain or more general to stressors, which may contribute to the allostatic load caused by stressors and migraine attacks on the brain.

scholarly journals A lifespan program of mouse synaptome architecture

2019 ◽  
Author(s):  
Mélissa Cizeron ◽  
Zhen Qiu ◽  
Babis Koniaris ◽  
Ragini Gokhale ◽  
Noboru H. Komiyama ◽  
...  
Keyword(s):  
Young Adults ◽  
Old Age ◽  
Mouse Brain ◽  
Protein Composition ◽  
Brain Regions ◽  
Intellectual Ability ◽  
Brain Circuits ◽  
Brain Circuitry ◽  
Wide Scale ◽  
The Brain

AbstractHow synapses change molecularly during the lifespan and across all brain circuits is unknown. We analyzed the protein composition of billions of individual synapses from birth to old age on a brain-wide scale in the mouse, revealing a program of changes in the lifespan synaptome architecture spanning individual dendrites to the systems level. Three major phases were uncovered, corresponding to human childhood, adulthood and old age. An arching trajectory of synaptome architecture drives the differentiation and specialization of brain regions to a peak in young adults before dedifferentiation returns the brain to a juvenile state. This trajectory underscores changing network organization and hippocampal physiology that may account for lifespan transitions in intellectual ability and memory, and the onset of behavioral disorders.One sentence summaryThe synaptome architecture of the mouse brain undergoes continuous changes that organize brain circuitry across the lifespan.

scholarly journals Functionnectome: a framework to analyse the contribution of brain circuits to fMRI

2021 ◽  
Author(s):  
Victor Nozais ◽  
Stephanie Forkel ◽  
Chris Foulon ◽  
Laurent Petit ◽  
Michel Thiebaut de Schotten
Keyword(s):  
White Matter ◽  
Functional Neuroimaging ◽  
Brain Regions ◽  
Functional Networks ◽  
Language Functions ◽  
Brain Circuits ◽  
Novel Method ◽  
Joint Contribution ◽  
The Relationship ◽  
The Brain

Abstract In recent years, the field of functional neuroimaging has moved from a pure localisationist approach of isolated functional brain regions to a more integrated view of those regions within functional networks. The methods used to investigate such networks, however, rely on local signals in grey matter and are limited in identifying anatomical circuitries supporting the interaction between brain regions. Mapping the brain circuits mediating the functional signal between brain regions would propel forward our understanding of the brain’s functional signatures and dysfunctions. We developed a novel method to unravel the relationship between brain circuits and functions: The Functionnectome. The Functionectome combines the functional signal from fMRI with the anatomy of white matter brain circuits to unlock and chart the first maps of functional white matter. To showcase the versatility of this new method, we provide the first functional white matter maps revealing the joint contribution of connected areas to motor, working memory, and language functions. The Functionnectome comes with an open source companion software and opens new avenues into studying functional networks by applying the method to already existing dataset and beyond task fMRI.

scholarly journals Rhes protein transits from neuron to neuron and facilitates mutant huntingtin spreading in the brain.

2021 ◽  
Author(s):  
Uri Nimrod Ramirez Jarquin ◽  
Manish Sharma ◽  
Neelam Shahani ◽  
Yunqing Li ◽  
Siddaraju Boregowda ◽  
...  
Keyword(s):  
Protein Transport ◽  
Brain Slices ◽  
Brain Regions ◽  
Medium Spiny Neurons ◽  
Striatal Neurons ◽  
Spiny Neurons ◽  
Tunneling Nanotube ◽  
Intact Brain ◽  
Cortical Regions ◽  
The Brain

Rhes (RASD2) is a thyroid hormone-induced gene that regulates striatal motor activity and promotes neurodegeneration in Huntington disease (HD) and tauopathy. Previously, we showed that Rhes moves between cultured striatal neurons and transports the HD protein, polyglutamine-expanded huntingtin (mHTT) via tunneling nanotube (TNT)-like membranous protrusions. However, similar intercellular Rhes transport has not yet been demonstrated in the intact brain. Here, we report that Rhes induces TNT-like protrusions in the striatal medium spiny neurons (MSNs) and transported between dopamine-1 receptor (D1R)-MSNs and D2R-MSNs of intact striatum and organotypic brain slices. Notably, mHTT is robustly transported within the striatum and from the striatum to the cortical areas in the brain, and Rhes deletion diminishes such transport. Moreover, we also found transport of Rhes to the cortical regions following restricted expression in the MSNs of the striatum. Thus, Rhes is a first striatum-enriched protein demonstrated to move and transport mHTT between neurons and brain regions, providing new insights on interneuronal protein transport in the brain.

scholarly journals The PICO Study: Impact of Phenylalanine on Cognitive, Cerebral and Neurometabolic Parameters in Adult Patients with Phenylketonuria – a Randomized, Placebo-Controlled, Crossover, Non-inferiority Trial

2019 ◽  
Author(s):  
Roman Trepp ◽  
Raphaela Muri ◽  
Lenka Bosanska ◽  
Stephanie Abgottspon ◽  
Michel Hochuli ◽  
...  
Keyword(s):  
Working Memory ◽  
Memory Task ◽  
Brain Regions ◽  
Primary Objective ◽  
Adult Patients ◽  
Target Range ◽  
Neural Activation ◽  
Level Of Evidence ◽  
Double Blind ◽  
The Brain

Abstract Background The population of adult patients with early-treated phenylketonuria (PKU) following newborn screening is growing substantially. The ideal target range of blood Phe levels in adults outside pregnancy is discussed controversially. Therefore, prospective intervention studies are needed to evaluate the effects of an elevated Phe concentration on cognition and structural, functional and neurometabolic parameters of the brain. Methods The PICO (Phenylalanine and Its Impact on Cognition) Study evaluates the effect of a 4-week phenylalanine (Phe) load on cognition and cerebral parameters in 30 adults with early-treated PKU in a double-blind, randomized, placebo-controlled, crossover, non-inferiority trial. The primary objective of the PICO Study is to prospectively assess whether a temporarily elevated Phe level influences cognitive performance in adults with early-treated PKU. As secondary objective, the PICO Study will elucidate cerebral and neurometabolic mechanisms, which accompany changes in Phe concentration using advanced neuroimaging methods. In addition to the intervention study, cognition, structural and functional parameters of the brain of adult patients with early-treated PKU will be cross-sectionally compared to healthy controls, who will be comparable with regard to age, gender and education level. Advanced MR-techniques will be used to investigate intensity of neural activation during the working memory task (fMRI), strength of functional connectivity between brain regions related to performance in working memory (rsfMRI), white matter integrity (DTI), cerebral blood flow (ASL) and brain Phe concentrations (MRS). Discussion Using a combination of neuropsychological and neuroimaging data, the PICO study will considerably contribute to improve the currently insufficient level of evidence on how adult patients with early-treated PKU should be managed.

scholarly journals Visual stability

2011 ◽  
Vol 366 (1564) ◽  
pp. 468-475 ◽  
Author(s):  
David Melcher
Keyword(s):  
Cognitive Neuroscience ◽  
State Of The Art ◽  
Brain Regions ◽  
Clinical Neurology ◽  
Visual Stability ◽  
Retinal Motion ◽  
Brain Circuits ◽  
The World ◽  
The Brain

Our vision remains stable even though the movements of our eyes, head and bodies create a motion pattern on the retina. One of the most important, yet basic, feats of the visual system is to correctly determine whether this retinal motion is owing to real movement in the world or rather our own self-movement. This problem has occupied many great thinkers, such as Descartes and Helmholtz, at least since the time of Alhazen. This theme issue brings together leading researchers from animal neurophysiology, clinical neurology, psychophysics and cognitive neuroscience to summarize the state of the art in the study of visual stability. Recently, there has been significant progress in understanding the limits of visual stability in humans and in identifying many of the brain circuits involved in maintaining a stable percept of the world. Clinical studies and new experimental methods, such as transcranial magnetic stimulation, now make it possible to test the causal role of different brain regions in creating visual stability and also allow us to measure the consequences when the mechanisms of visual stability break down.

Experimental models of spatial neglect

e-Neuroforum ◽  
2012 ◽  
Vol 18 (1) ◽  
Author(s):  
M. Wilke ◽  
P. Dechent ◽  
C. Schmidt-Samoa
Keyword(s):  
Nonhuman Primates ◽  
Brain Activity ◽  
Brain Regions ◽  
Experimental Models ◽  
Spatial Neglect ◽  
Distributed Network ◽  
Healthy Individuals ◽  
Detailed Understanding ◽  
Brain Circuits ◽  
The Brain

AbstractSpatial neglect is a debilitating neuropsy­chological disorder that is characterized by an impaired or lost ability to explore the space contralateral to the lesion and to re­act to stimuli presented on this side. Lesion sites that have been implicated in spatial ne­glect form a widely distributed network con­sisting of a number of cortical (i.e., frontopa­rietal) and subcortical (i.e., thalamic) areas that are activated during attention and vi­suomotor tasks in healthy individuals. While detailed understanding of the brain circuits and mechanisms involved in spatial neglect is a prerequisite for the development of ef­fective therapies, this has proven to be dif­ficult in human patients because of the size and variability of lesion sites. Therefore, ex­perimental models where predefined brain regions can be systematically inactivated are of great advantage. Neglect models have been developed in nonhuman primates in whom it is possible to pharmacologically in­activate small brain regions and in humans by means of noninvasive stimulation/inacti­vation methods such as transcranial magnet­ic stimulation. In this article, we discuss theo­ries about the mechanisms of spatial neglect such as the hemispheric imbalance model and the supporting experimental evidence, with an emphasis on imaging experiments that have explored the effects of lesions on dynamic brain activity.

scholarly journals Associations between Melatonin, Neuroinflammation, and Brain Alterations in Depression

2021 ◽  
Vol 23 (1) ◽  
pp. 305
Author(s):  
Eunsoo Won ◽  
Kyoung-Sae Na ◽  
Yong-Ku Kim
Keyword(s):  
Emotional Regulation ◽  
Inflammatory Responses ◽  
Underlying Mechanism ◽  
Brain Regions ◽  
Immune Markers ◽  
Inflammatory Conditions ◽  
Brain Structure And Function ◽  
Immune System Regulation ◽  
And Function ◽  
The Brain

Pro-inflammatory systemic conditions that can cause neuroinflammation and subsequent alterations in brain regions involved in emotional regulation have been suggested as an underlying mechanism for the pathophysiology of major depressive disorder (MDD). A prominent feature of MDD is disruption of circadian rhythms, of which melatonin is considered a key moderator, and alterations in the melatonin system have been implicated in MDD. Melatonin is involved in immune system regulation and has been shown to possess anti-inflammatory properties in inflammatory conditions, through both immunological and non-immunological actions. Melatonin has been suggested as a highly cytoprotective and neuroprotective substance and shown to stimulate all stages of neuroplasticity in animal models. The ability of melatonin to suppress inflammatory responses through immunological and non-immunological actions, thus influencing neuroinflammation and neurotoxicity, along with subsequent alterations in brain regions that are implicated in depression, can be demonstrated by the antidepressant-like effects of melatonin. Further studies that investigate the associations between melatonin, immune markers, and alterations in the brain structure and function in patients with depression could identify potential MDD biomarkers.

scholarly journals Optogenetic activation of nonhuman primate cortical and subcortical brain circuits highlights detection capabilities of MEG source imaging

2020 ◽  
Author(s):  
GE Alberto ◽  
JR Stapleton-Kotloski ◽  
DC Klorig ◽  
ER Rogers ◽  
C Constantinidis ◽  
...  
Keyword(s):  
Brain Regions ◽  
Temporal Networks ◽  
Source Imaging ◽  
Magnetic Source Imaging ◽  
Accurate Localization ◽  
Brain Circuits ◽  
Intact Brain ◽  
Detection Capabilities ◽  
Deep Sources ◽  
Highlights Detection

ABSTRACTMagnetoencephalography (MEG) measures neuromagnetic activity with high temporal, and theoretically, high spatial resolution. However, the ability of magnetic source imaging (MSI) to localize deep sources is uncertain. We developed an experimental platform combining MEG-compatible optogenetic techniques in non-human primates (NHPs) to test the ability of MEG/MSI to image deep signals. We demonstrate localization of optogenetically-evoked signals to known sources in the superficial arcuate sulcus of cortex and in CA3 of hippocampus at a resolution of 750 µm3. In response to stimulation of arcuate sulcus and hippocampus, we detected activation in subcortical and thalamic structures, or extended temporal networks, respectively. This is the first demonstration of accurate localization of deep sources within an intact brain using a novel combination of optogenetics with MEG/MSI. This approach is suitable for exploring causal relationships between discrete brain regions through precise optogenetic control and simultaneous whole brain recording.

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