Sparsity enables estimation of both subcortical and cortical activity from MEG and EEG

Subcortical structures play a critical role in brain function. However, options for assessing electrophysiological activity in these structures are limited. Electromagnetic fields generated by neuronal activity in subcortical structures can be recorded noninvasively, using magnetoencephalography (MEG) and electroencephalography (EEG). However, these subcortical signals are much weaker than those generated by cortical activity. In addition, we show here that it is difficult to resolve subcortical sources because distributed cortical activity can explain the MEG and EEG patterns generated by deep sources. We then demonstrate that if the cortical activity is spatially sparse, both cortical and subcortical sources can be resolved with M/EEG. Building on this insight, we develop a hierarchical sparse inverse solution for M/EEG. We assess the performance of this algorithm on realistic simulations and auditory evoked response data, and show that thalamic and brainstem sources can be correctly estimated in the presence of cortical activity. Our work provides alternative perspectives and tools for characterizing electrophysiological activity in subcortical structures in the human brain.

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Metabolic and Molecular Aspects of the Critical Role of Docosahexaenoic Acid in Human Brain Function

Human Brain Evolution ◽

10.1002/9780470609880.ch4 ◽

2010 ◽

pp. 65-76

Author(s):

J. Thomas Brenna

Keyword(s):

Docosahexaenoic Acid ◽

Human Brain ◽

Brain Function ◽

Critical Role ◽

Molecular Aspects

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Lessons from the Human Brain: Neuronal Activity Related to Cognition

The Neuroscientist ◽

10.1177/107385849800400417 ◽

1998 ◽

Vol 4 (4) ◽

pp. 285-300 ◽

Cited By ~ 21

Author(s):

George A. Ojemann ◽

Steven G. Ojemann ◽

Itzhak Fried

Keyword(s):

Human Brain ◽

Neuronal Activity ◽

Medial Temporal Lobe ◽

Extracellular Recording ◽

Clinical Settings ◽

Subcortical Structures ◽

Cognitive Measures ◽

Specific Behavior ◽

Limited Experience ◽

Language Measures

Several special clinical settings provide opportunities for extracellular recording of neuronal activity in the human brain during measures of cognition. The limited experience with recordings obtained from human temporal and frontal cortex, medial temporal lobe, and subcortical structures in association with language, visuospatial processes, memory, learning, and music is reviewed here. The frequency of activity in a high proportion of neurons changes with a specific behavior. These neurons are widely distributed in both hemispheres. Relative inhibition of activity is prominent in cortical recordings made during language measures, particularly in the dominant hemisphere. Widespread excitation is prominent in recordings made during measures of recent explicit memory and learning. However, any individual neuron often has a narrow behavioral repertory, with activation to only one specific behavior in a range of behaviors. Some of the behaviors associated with consistent changes are not intuitively obvious. Nearby neurons often have different behavioral repertories. A few patterns of activity that may represent specific coding for a behavior, in some cases even sparse coding, have been identified. Neuronal recording in humans during cognitive measures provides an additional perspective on the neurobiological substrate of cognition that complements findings from other techniques.

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Biogenic metallic elements in the human brain?

Science Advances ◽

10.1126/sciadv.abf6707 ◽

2021 ◽

Vol 7 (24) ◽

pp. eabf6707

Author(s):

James Everett ◽

Frederik Lermyte ◽

Jake Brooks ◽

Vindy Tjendana-Tjhin ◽

Germán Plascencia-Villa ◽

...

Keyword(s):

Human Brain ◽

Brain Function ◽

Critical Role ◽

Metallic Copper ◽

Amyloid Plaque ◽

Normal Brain ◽

Metallic Elements ◽

Normal Brain Function ◽

The Brain ◽

Positively Charged

The chemistry of copper and iron plays a critical role in normal brain function. A variety of enzymes and proteins containing positively charged Cu+, Cu2+, Fe2+, and Fe3+ control key processes, catalyzing oxidative metabolism and neurotransmitter and neuropeptide production. Here, we report the discovery of elemental (zero–oxidation state) metallic Cu0 accompanying ferromagnetic elemental Fe0 in the human brain. These nanoscale biometal deposits were identified within amyloid plaque cores isolated from Alzheimer’s disease subjects, using synchrotron x-ray spectromicroscopy. The surfaces of nanodeposits of metallic copper and iron are highly reactive, with distinctly different chemical and magnetic properties from their predominant oxide counterparts. The discovery of metals in their elemental form in the brain raises new questions regarding their generation and their role in neurochemistry, neurobiology, and the etiology of neurodegenerative disease.

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Toward a neuroscope: An application of high-performance computing for real-time evaluation of brain function using MRI

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172346 ◽

1994 ◽

Vol 52 ◽

pp. 922-923

Author(s):

C. S. Potter ◽

C. D. Gregory ◽

H. D. Morris ◽

Z.-P. Liang ◽

P. C. Lauterbur

Keyword(s):

Human Brain ◽

Brain Function ◽

High Performance ◽

Complex Signal ◽

Time Step ◽

Brain Organization ◽

Cognitive Studies ◽

Positron Emission ◽

Imaging And Spectroscopy ◽

3D Anatomy

Over the past few years, several laboratories have demonstrated that changes in local neuronal activity associated with human brain function can be detected by magnetic resonance imaging and spectroscopy. Using these methods, the effects of sensory and motor stimulation have been observed and cognitive studies have begun. These new methods promise to make possible even more rapid and extensive studies of brain organization and responses than those now in use, such as positron emission tomography.Human brain studies are enormously complex. Signal changes on the order of a few percent must be detected against the background of the complex 3D anatomy of the human brain. Today, most functional MR experiments are performed using several 2D slice images acquired at each time step or stimulation condition of the experimental protocol. It is generally believed that true 3D experiments must be performed for many cognitive experiments. To provide adequate resolution, this requires that data must be acquired faster and/or more efficiently to support 3D functional analysis.

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Frontier concept of rabi chip for intelligent humanoid

Journal of Analytical Chromatography and Spectroscopy ◽

10.24294/jacs.v1i2.908 ◽

2018 ◽

Vol 1 (2) ◽

Author(s):

Preecha Yupapin ◽

Amiri I. S. ◽

Ali J. ◽

Ponsuwancharoen N. ◽

Youplao P.

Keyword(s):

Human Brain ◽

Brain Function ◽

Rabi Oscillation ◽

Liquid Core ◽

Brain Surface ◽

Dipole Oscillation ◽

On Chip ◽

The Brain ◽

Robotic Applications ◽

Atom System

The sequence of the human brain can be configured by the originated strongly coupling fields to a pair of the ionic substances(bio-cells) within the microtubules. From which the dipole oscillation begins and transports by the strong trapped force, which is known as a tweezer. The tweezers are the trapped polaritons, which are the electrical charges with information. They will be collected on the brain surface and transport via the liquid core guide wave, which is the mixture of blood content and water. The oscillation frequency is called the Rabi frequency, is formed by the two-level atom system. Our aim will manipulate the Rabi oscillation by an on-chip device, where the quantum outputs may help to form the realistic human brain function for humanoid robotic applications.

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Integration of fMRI, NIROT and ERP for studies of human brain function

Magnetic Resonance Imaging ◽

10.1016/j.mri.2005.12.039 ◽

2006 ◽

Vol 24 (4) ◽

pp. 507-513 ◽

Cited By ~ 12

Author(s):

John C. Gore ◽

Silvina G. Horovitz ◽

Christopher J. Cannistraci ◽

Pavel Skudlarski

Keyword(s):

Human Brain ◽

Brain Function

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The brain timewise: how timing shapes and supports brain function

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2014.0170 ◽

2015 ◽

Vol 370 (1668) ◽

pp. 20140170 ◽

Cited By ~ 39

Author(s):

Riitta Hari ◽

Lauri Parkkonen

Keyword(s):

Human Brain ◽

Brain Imaging ◽

Brain Function ◽

Temporal Dynamics ◽

Generative Models ◽

Network Activity ◽

Brain Diseases ◽

Specific Information ◽

Non Invasive ◽

The Brain

We discuss the importance of timing in brain function: how temporal dynamics of the world has left its traces in the brain during evolution and how we can monitor the dynamics of the human brain with non-invasive measurements. Accurate timing is important for the interplay of neurons, neuronal circuitries, brain areas and human individuals. In the human brain, multiple temporal integration windows are hierarchically organized, with temporal scales ranging from microseconds to tens and hundreds of milliseconds for perceptual, motor and cognitive functions, and up to minutes, hours and even months for hormonal and mood changes. Accurate timing is impaired in several brain diseases. From the current repertoire of non-invasive brain imaging methods, only magnetoencephalography (MEG) and scalp electroencephalography (EEG) provide millisecond time-resolution; our focus in this paper is on MEG. Since the introduction of high-density whole-scalp MEG/EEG coverage in the 1990s, the instrumentation has not changed drastically; yet, novel data analyses are advancing the field rapidly by shifting the focus from the mere pinpointing of activity hotspots to seeking stimulus- or task-specific information and to characterizing functional networks. During the next decades, we can expect increased spatial resolution and accuracy of the time-resolved brain imaging and better understanding of brain function, especially its temporal constraints, with the development of novel instrumentation and finer-grained, physiologically inspired generative models of local and network activity. Merging both spatial and temporal information with increasing accuracy and carrying out recordings in naturalistic conditions, including social interaction, will bring much new information about human brain function.

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