Coherent Electrical Activity Between Vibrissa Sensory Areas of Cerebellum and Neocortex Is Enhanced During Free Whisking

2002 ◽  
Vol 87 (4) ◽  
pp. 2137-2148 ◽  
Author(s):  
Sean M. O'Connor ◽  
Rune W. Berg ◽  
David Kleinfeld
Keyword(s):  
Electrical Activity ◽  
Sensory Input ◽  
Field Potential ◽  
Sensory Cortex ◽  
Brain Areas ◽  
Low Coherence ◽  
Primary Sensory Cortex ◽  
High Level ◽  
The Brain ◽  
Local Field Potential Lfp

We tested if coherent signaling between the sensory vibrissa areas of cerebellum and neocortex in rats was enhanced as they whisked in air. Whisking was accompanied by 5- to 15-Hz oscillations in the mystatial electromyogram, a measure of vibrissa position, and by 5- to 20-Hz oscillations in the differentially recorded local field potential (∇LFP) within the vibrissa area of cerebellum and within the ∇LFP of primary sensory cortex. We observed that only 10% of the activity in either cerebellum or sensory neocortex was significantly phase-locked to rhythmic motion of the vibrissae; the extent of this modulation is in agreement with the results from previous single-unit measurements in sensory neocortex. In addition, we found that 40% of the activity in the vibrissa areas of cerebellum and neocortex was significantly coherent during periods of whisking. The relatively high level of coherence between these two brain areas, in comparison with their relatively low coherence with whisking per se, implies that the vibrissa areas of cerebellum and neocortex communicate in a manner that is incommensurate with whisking. To the extent that the vibrissa areas of cerebellum and neocortex communicate over the same frequency band as that used by whisking, these areas must multiplex electrical activity that is internal to the brain with activity that is that phase-locked to vibrissa sensory input.

scholarly journals Thalamocortical spectral transmission relies on balanced input strengths

2020 ◽  
Author(s):  
Matteo Saponati ◽  
Jordi Garcia-Ojalvo ◽  
Enrico Cataldo ◽  
Alberto Mazzoni
Keyword(s):  
Sensory Information ◽  
Field Potential ◽  
Sensory Cortex ◽  
Inhibitory Neurons ◽  
Spectral Transmission ◽  
Sensory Transmission ◽  
Thalamocortical Connections ◽  
Primary Sensory Cortex ◽  
Spiking Network ◽  
The Brain

AbstractThe thalamus is a key element of sensory transmission in the brain, as all sensory information is processed by the thalamus before reaching the cortex. The thalamus is known to gate and select sensory streams through a modulation of its internal activity in which spindle oscillations play a preponderant role, but the mechanism underlying this process is not completely understood. In particular, how do thalamocortical connections convey stimulus-driven information selectively over the background of thalamic internally generated activity (such as spindle oscillations)? Here we investigate this issue with a spiking network model of connectivity between thalamus and primary sensory cortex reproducing the local field potential of both areas. We found two features of the thalamocortical dynamics that filter out spindle oscillations: i) spindle oscillations are weaker in neurons projecting to the cortex, ii) the resonance dynamics of cortical networks selectively blocks frequency in the range encompassing spindle oscillations. This latter mechanism depends on the balance of the strength of thalamocortical connections toward excitatory and inhibitory neurons in the cortex. Our results pave the way toward an integrated understanding of the sensory streams traveling between the periphery and the cortex.

scholarly journals Human Development XI: The Structure of the Cerebral Cortex. Are There Really Modules in the Brain?

2007 ◽  
Vol 7 ◽  
pp. 1922-1929 ◽  
Author(s):  
Tyge Dahl Hermansen ◽  
Søren Ventegodt ◽  
Isack Kandel
Keyword(s):  
Cerebral Cortex ◽  
Brain Activity ◽  
Sensory Cortex ◽  
Biological Information ◽  
Human Consciousness ◽  
Primary Sensory Cortex ◽  
Sensory Maps ◽  
The World ◽  
The Brain ◽  
The Universe

The structure of human consciousness is thought to be closely connected to the structure of cerebral cortex. One of the most appreciated concepts in this regard is the Szanthagothei model of a modular building of neo-cortex. The modules are believed to organize brain activity pretty much like a computer. We looked at examples in the literature and argue that there is no significant evidence that supports Szanthagothei's model. We discuss the use of the limited genetic information, the corticocortical afferents termination and the columns in primary sensory cortex as arguments for the existence of the cortex-module. Further, we discuss the results of experiments with Luminization Microscopy (LM) colouration of myalinized fibres, in which vertical bundles of afferent/efferent fibres that could support the cortex module are identified. We conclude that sensory maps seem not to be an expression for simple specific connectivity, but rather to be functional defined. We also conclude that evidence for the existence of the postulated module or column does not exist in the discussed material. This opens up for an important discussion of the brain as functionally directed by biological information (information-directed self-organisation), and for consciousness being closely linked to the structure of the universe at large. Consciousness is thus not a local phenomena limited to the brain, but a much more global phenomena connected to the wholeness of the world.

scholarly journals Sensory cortex is optimised for prediction of future input

2017 ◽  
Author(s):  
Yosef Singer ◽  
Yayoi Teramoto ◽  
Ben D. B. WiIJmore ◽  
Andrew J. King ◽  
Jan W. H. Schnupp ◽  
...  
Keyword(s):  
Sensory Processing ◽  
Cortical Neurons ◽  
Sensory Input ◽  
Receptive Fields ◽  
Primary Auditory Cortex ◽  
Feedforward Neural Networks ◽  
Sensory Cortex ◽  
Natural Scenes ◽  
Recent Past ◽  
The Brain

Neurons in sensory cortex are tuned to diverse features in natural scenes. But what determines which features neurons become selective to? Here we explore the idea that neuronal selectivity is optimised to represent features in the recent past of sensory input that best predict immediate future inputs. We tested this hypothesis using simple feedforward neural networks, which were trained to predict the next few video or audio frames in clips of natural scenes. The networks developed receptive fields that closely matched those of real cortical neurons, including the oriented spatial tuning of primary visual cortex, the frequency selectivity of primary auditory cortex and, most notably, in their temporal tuning properties. Furthermore, the better a network predicted future inputs the more closely its receptive fields tended to resemble those in the brain. This suggests that sensory processing is optimised to extract those features with the most capacity to predict future input.Impact statementPrediction of future input explains diverse neural tuning properties in sensory cortex.

scholarly journals Effect of amplitude correlations on coherence in the local field potential

2014 ◽  
Vol 112 (4) ◽  
pp. 741-751 ◽  
Author(s):  
Ramanujan Srinath ◽  
Supratim Ray
Keyword(s):  
Local Field ◽  
Local Field Potential ◽  
Multiple Scales ◽  
Field Potential ◽  
Interelectrode Distance ◽  
Study Phase ◽  
Temporal Correlations ◽  
Two Factors ◽  
The Brain ◽  
Local Field Potential Lfp

Neural activity across the brain shows both spatial and temporal correlations at multiple scales, and understanding these correlations is a key step toward understanding cortical processing. Correlation in the local field potential (LFP) recorded from two brain areas is often characterized by computing the coherence, which is generally taken to reflect the degree of phase consistency across trials between two sites. Coherence, however, depends on two factors—phase consistency as well as amplitude covariation across trials—but the spatial structure of amplitude correlations across sites and its contribution to coherence are not well characterized. We recorded LFP from an array of microelectrodes chronically implanted in the primary visual cortex of monkeys and studied correlations in amplitude across electrodes as a function of interelectrode distance. We found that amplitude correlations showed a similar trend as coherence as a function of frequency and interelectrode distance. Importantly, even when phases were completely randomized between two electrodes, amplitude correlations introduced significant coherence. To quantify the contributions of phase consistency and amplitude correlations to coherence, we simulated pairs of sinusoids with varying phase consistency and amplitude correlations. These simulations confirmed that amplitude correlations can significantly bias coherence measurements, resulting in either over- or underestimation of true phase coherence. Our results highlight the importance of accounting for the correlations in amplitude while using coherence to study phase relationships across sites and frequencies.

scholarly journals Thalamocortical Spectral Transmission Relies on Balanced Input Strengths

2021 ◽  
Author(s):  
Matteo Saponati ◽  
Jordi Garcia-Ojalvo ◽  
Enrico Cataldo ◽  
Alberto Mazzoni
Keyword(s):  
Field Potential ◽  
Inhibitory Neurons ◽  
Feedforward Network ◽  
Sensory Transmission ◽  
Thalamocortical Connections ◽  
Primary Sensory Cortex ◽  
Spiking Network ◽  
Back Ground ◽  
Corticothalamic Feedback ◽  
The Brain

AbstractThe thalamus is a key element of sensory transmission in the brain, as it gates and selects sensory streams through a modulation of its internal activity. A preponderant role in these functions is played by its internal activity in the alpha range ([8–14] Hz), but the mechanism underlying this process is not completely understood. In particular, how do thalamocortical connections convey stimulus driven information selectively over the back-ground of thalamic internally generated activity? Here we investigate this issue with a spiking network model of feedforward connectivity between thalamus and primary sensory cortex reproducing the local field potential of both areas. We found that in a feedforward network, thalamic oscillations in the alpha range do not entrain cortical activity for two reasons: (i) alpha range oscillations are weaker in neurons projecting to the cortex, (ii) the gamma resonance dynamics of cortical networks hampers oscillations over the 10–20 Hz range thus weakening alpha range oscillations. This latter mechanism depends on the balance of the strength of thalamocortical connections toward excitatory and inhibitory neurons in the cortex. Our results highlight the relevance of corticothalamic feedback to sustain alpha range oscillations and pave the way toward an integrated understanding of the sensory streams traveling between the periphery and the cortex.

Electroencephalography and Local Field Potentials in Animals

2015 ◽  
Author(s):  
Sean Reed ◽  
Sonia Jego ◽  
Antoine Adamantidis
Keyword(s):  
Animal Models ◽  
Local Field ◽  
Field Potential ◽  
Electrical Current ◽  
Ionic Currents ◽  
Synaptic Activity ◽  
Field Potentials ◽  
Motivational States ◽  
The Brain ◽  
Local Field Potential Lfp

This chapter discusses the history, practice, and application of electroencephalography (EEG) and local field potential (LFP) recordings, with a particular focus on animal models. EEG measures the fluctuations of electrical activity resulting from ionic currents in the brain. These measurements are often taken from electrodes placed on the surface of the scalp, or in animal models, directly on the skull. LFP recordings are more invasive, measuring electrical current from all nearby dendritic synaptic activity within a volume of tissue. These two techniques are useful in determining how neural activity can synchronize during different behavioral or motivational states.

scholarly journals Altered Postnatal Development of Cortico—Hippocampal Neuronal Electric Activity in Mice Deficient for the Mitochondrial Aspartate—Glutamate Transporter

2011 ◽  
Vol 32 (2) ◽  
pp. 306-317 ◽  
Author(s):  
Marta Gómez-Galán ◽  
Julia Makarova ◽  
Irene Llorente-Folch ◽  
Takeyori Saheki ◽  
Beatriz Pardo ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Brain Metabolism ◽  
Glutamate Transporter ◽  
Field Potential ◽  
Electric Activity ◽  
Postnatal Growth ◽  
Epileptic Activity ◽  
And Control ◽  
The Brain ◽  
Local Field Potential Lfp

The deficiency in the mitochondrial aspartate/glutamate transporter Aralar/AGC1 results in a loss of the malate-aspartate NADH shuttle in the brain neurons, hypomyelination, and additional defects in the brain metabolism. We studied the development of cortico/hippocampal local field potential (LFP) in Aralar/AGC1 knockout (KO) mice. Laminar profiles of LFP, evoked potentials, and unit activity were recorded under anesthesia in young (P15 to P22) Aralar-KO and control mice as well as control adults. While LFP power increased 3 to 7 times in both cortex and hippocampus of control animals during P15 to P22, the Aralar-KO specimens hardly progressed. The divergence was more pronounced in the CA3/hilus region. In parallel, spontaneous multiunit activity declined severely in KO mice. Postnatal growth of hippocampal-evoked potentials was delayed in KO mice, and indicated abnormal synaptic and spike electrogenesis and reduced output at P20 to P22. The lack of LFP development in KO mice was accompanied by the gradual appearance of epileptic activity in the CA3/hilus region that evolved to status epilepticus. Strikingly, CA3 bursts were poorly conducted to the CA1 field. We conclude that disturbed substrate supply to neuronal mitochondria impairs development of cortico—hippocampal LFPs. Aberrant neuronal electrogenesis and reduced neuron output may explain circuit dysfunction and phenotype deficiencies.

Central release of oxytocin and the ventromedial hypothalamus

2007 ◽  
Vol 35 (5) ◽  
pp. 1247-1251 ◽  
Author(s):  
N. Sabatier ◽  
I. Rowe ◽  
G. Leng
Keyword(s):  
Food Intake ◽  
Electrical Activity ◽  
Ventromedial Hypothalamus ◽  
Receptor Expression ◽  
Brain Areas ◽  
Magnocellular Neurons ◽  
Peptide Receptor ◽  
Peptide Release ◽  
The Brain ◽  
Social Behaviours

Recent studies on the regulation of social behaviours by neuropeptides indicate that it is the distribution of peptide receptor expression in particular brain areas that determines the specificity of peptide actions; and that, accordingly, peptides can evoke specific behaviours when administered centrally without temporal or spatial selectivity of administration. The release of neuropeptides at synaptic sites appears irrelevant, and in the brain, some peptides are released mainly from dendrites rather than from nerve endings. Dendritic peptide release can be long lasting, semi-independent of electrical activity, and allows the diffusion of peptides to distant targets. The peptide oxytocin regulates many behaviours; in particular, it inhibits food intake. Centrally, oxytocin is released in large amounts by the dendrites of hypothalamic magnocellular neurons. This mini-review considers the possible involvement of dendritically released oxytocin in the regulation of food intake by its actions on the ventromedial hypothalamus.

scholarly journals Effects of Propofol and Ketamine on The Neural Oscillations in CA1 of Rat Intact Hippocampus

2020 ◽  
Author(s):  
Zhang Yu ◽  
Ping Chen ◽  
Zhi-yi Tu ◽  
Yi-heng Liu ◽  
Zhi-ru Wang ◽  
...  
Keyword(s):  
Field Potential ◽  
Inhibitory Effect ◽  
Neural Oscillations ◽  
General Anesthetics ◽  
Bath Application ◽  
Spectrum Intensity ◽  
Underlying Mechanisms ◽  
The Brain ◽  
Local Field Potential Lfp

Abstract In this study, in vitro intact hippocampal preparation model was utilized to observe the effects of propofol and ketamine on the neural oscillations in CA1 of rat hippocampus. The intact hippocampi were dissected from the brain tissues of rats aged 14-16 days postnatal. Local field potential (LFP) recordings were performed with propofol and ketamine bath application at different concentrations. The power spectrum intensity of LFP in all the frequency bands, including delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), beta (13-30 Hz) and gamma (30-80 Hz), were inhibited in a concentrationdependent manner by both general anesthetics. In order to further investigate the underlying mechanisms, the major binding site of propofol and ketamine were blocked respectively by picrotoxin and (2R)-amino-5-phosphonopentanoate when bath applying the general anesthetics. It revealed that the inhibitory effect of propofol on hippocampal oscillations might be via γ-aminobutyric acid A receptor, while the inhibitory effect of ketamine might be unconcerned with N-methyl-D-aspartic acid receptor.

Sign in / Sign up

Export Citation Format

Share Document