Two frequency bands contain the most stimulus-related information in visual cortex

AbstractSensory cortices represent the world through the activity of diversely tuned cells. How the activity of single cells is coordinated within populations and across sensory hierarchies is largely unknown. Cortical oscillations may coordinate local and distributed neuronal groups. Using datasets from intracortical multi-electrode recordings and from large-scale electrocorticography (ECoG) grids, we investigated how visual features could be extracted from the local field potential (LFP) and how this compared with the information available from multi-unit activity (MUA). MUA recorded from macaque V1 contained comparable amounts of information as simultaneously recorded LFP power in two frequency bands, one in the alpha-beta band and the other in the gamma band. ECoG-LFP contained information in the same bands as microelectrode-LFP, even when identifying natural scenes. The fact that information was contained in the same bands in both intracortical and ECoG recordings suggests that oscillatory activity could play similar roles at both spatial scales.

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Multichannel brain recordings in behaving Drosophila reveal oscillatory activity and local coherence in response to sensory stimulation and circuit activation

Journal of Neurophysiology ◽

10.1152/jn.00414.2013 ◽

2013 ◽

Vol 110 (7) ◽

pp. 1703-1721 ◽

Cited By ~ 19

Author(s):

Angelique C. Paulk ◽

Yanqiong Zhou ◽

Peter Stratton ◽

Li Liu ◽

Bruno van Swinderen

Keyword(s):

Visual Stimulation ◽

Sensory Modality ◽

Field Potential ◽

Brain Regions ◽

Oscillatory Activity ◽

Insect Brain ◽

Sensory Stimuli ◽

Multichannel Recording ◽

Frequency Bands

Neural networks in vertebrates exhibit endogenous oscillations that have been associated with functions ranging from sensory processing to locomotion. It remains unclear whether oscillations may play a similar role in the insect brain. We describe a novel “whole brain” readout for Drosophila melanogaster using a simple multichannel recording preparation to study electrical activity across the brain of flies exposed to different sensory stimuli. We recorded local field potential (LFP) activity from >2,000 registered recording sites across the fly brain in >200 wild-type and transgenic animals to uncover specific LFP frequency bands that correlate with: 1) brain region; 2) sensory modality (olfactory, visual, or mechanosensory); and 3) activity in specific neural circuits. We found endogenous and stimulus-specific oscillations throughout the fly brain. Central (higher-order) brain regions exhibited sensory modality-specific increases in power within narrow frequency bands. Conversely, in sensory brain regions such as the optic or antennal lobes, LFP coherence, rather than power, best defined sensory responses across modalities. By transiently activating specific circuits via expression of TrpA1, we found that several circuits in the fly brain modulate LFP power and coherence across brain regions and frequency domains. However, activation of a neuromodulatory octopaminergic circuit specifically increased neuronal coherence in the optic lobes during visual stimulation while decreasing coherence in central brain regions. Our multichannel recording and brain registration approach provides an effective way to track activity simultaneously across the fly brain in vivo, allowing investigation of functional roles for oscillations in processing sensory stimuli and modulating behavior.

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How Global Are Olfactory Bulb Oscillations?

Journal of Neurophysiology ◽

10.1152/jn.00478.2010 ◽

2010 ◽

Vol 104 (3) ◽

pp. 1768-1773 ◽

Cited By ~ 20

Author(s):

Leslie M. Kay ◽

Philip Lazzara

Keyword(s):

Olfactory Bulb ◽

Local Field ◽

Local Field Potential ◽

Field Potential ◽

Beta Band ◽

Recording Site ◽

Potential Oscillations ◽

Frequency Bands ◽

Surface Electrodes ◽

Analysis Window

Previous studies in waking animals have shown that the frequency structure of olfactory bulb (OB) local field potential oscillations is very similar across the OB, but large low-impedance surface electrodes may have favored highly coherent events, averaging out local inhomogeneities. We tested the hypothesis that OB oscillations represent spatially homogeneous phenomena at all scales. We used pairs of concentric electrodes (200 μm outer shaft surrounding an inner 2–3 μm recording site) beginning on the dorsal OB at anterior and medial locations in urethane-anesthetized rats and measured local field potential responses at successive 200 μm depths before and during odor stimulation. Within locations (outer vs. inner lead on a single probe), on the time scale of 0.5 s, coherence in all frequency bands was significant, but on larger time scales (10 s), only respiratory (1–4 Hz) and beta (15–30 Hz) oscillations showed prominent peaks. Across locations, coherence in all frequency bands was significantly lower for both sizes of electrodes at all depths but the most superficial 600 μm. Near the pial surface, coherence across outer (larger) electrodes at different sites was equal to coherence across outer and inner (small) electrodes within a single site and larger than coherence across inner electrodes at different sites. Overall, the beta band showed the largest coherence across bulbar sites and electrodes. Therefore larger electrodes at the surface of the OB favor globally coherent events, and at all depths, coherence depends on the type of oscillation (beta or gamma) and duration of the analysis window.

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Dynamic large-scale connectivity of intrinsic cortical oscillations supports adaptive listening in challenging conditions

PLoS Biology ◽

10.1371/journal.pbio.3001410 ◽

2021 ◽

Vol 19 (10) ◽

pp. e3001410

Author(s):

Mohsen Alavash ◽

Sarah Tune ◽

Jonas Obleser

Keyword(s):

Target Word ◽

Large Scale ◽

Word Identification ◽

Oscillatory Activity ◽

Neural Systems ◽

Neural Oscillations ◽

Frontoparietal Network ◽

Cortical Oscillations ◽

Listening Behavior ◽

Flexible Adaptation

In multi-talker situations, individuals adapt behaviorally to the listening challenge mostly with ease, but how do brain neural networks shape this adaptation? We here establish a long-sought link between large-scale neural communications in electrophysiology and behavioral success in the control of attention in difficult listening situations. In an age-varying sample of N = 154 individuals, we find that connectivity between intrinsic neural oscillations extracted from source-reconstructed electroencephalography is regulated according to the listener’s goal during a challenging dual-talker task. These dynamics occur as spatially organized modulations in power-envelope correlations of alpha and low-beta neural oscillations during approximately 2-s intervals most critical for listening behavior relative to resting-state baseline. First, left frontoparietal low-beta connectivity (16 to 24 Hz) increased during anticipation and processing of spatial-attention cue before speech presentation. Second, posterior alpha connectivity (7 to 11 Hz) decreased during comprehension of competing speech, particularly around target-word presentation. Connectivity dynamics of these networks were predictive of individual differences in the speed and accuracy of target-word identification, respectively, but proved unconfounded by changes in neural oscillatory activity strength. Successful adaptation to a listening challenge thus latches onto 2 distinct yet complementary neural systems: a beta-tuned frontoparietal network enabling the flexible adaptation to attentive listening state and an alpha-tuned posterior network supporting attention to speech.

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Discrimination of Changes in the Slopes of the Amplitude Spectra of Natural Images: Band-Limited Contrast and Psychometric Functions

Perception ◽

10.1068/p261011 ◽

1997 ◽

Vol 26 (8) ◽

pp. 1011-1025 ◽

Cited By ~ 12

Author(s):

David J Tolhurst ◽

Yoav Tadmor

Keyword(s):

Spatial Frequency ◽

Discrimination Task ◽

Spatial Scales ◽

Natural Images ◽

Natural Scenes ◽

Local Contrast ◽

Frequency Bands ◽

Amplitude Spectra ◽

Lower Frequency Band ◽

Band Limited

Thresholds were measured for discriminating changes in the slopes of the amplitude spectra of stimuli derived from photographs of natural scenes and from random-luminance patterns. The variety and magnitudes of the thresholds could be explained by a model based on the discrimination of the changes in band-limited local contrast. Different spatial scales of local contrast (or different spatial-frequency bands of about 1 octave) were implicated for different reference spectral slopes; the model implicated a lower frequency-band for stimuli with shallower amplitude spectra. The implications of the model were tested experimentally by using stimuli in which the spectra were changed within restricted spatial-frequency bands. When the amplitude spectra of the test and reference stimuli differed only within the implicated frequency bands, thresholds were affected little. However, when the test and reference spectra differed at all frequencies except those in the implicated bands, the thresholds were elevated markedly. The forms of the psychometric functions for the discrimination task were entirely compatible with the hypothesis that the task relies upon the ability to discriminate changes of contrast. The Weibull functions fitted to the data had slope parameters (β) in the range 1 to 3, compatible with discrimination of low (but suprathreshold) contrasts.

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Different Neural Frequency Bands Integrate Faces and Voices Differently in the Superior Temporal Sulcus

Journal of Neurophysiology ◽

10.1152/jn.90843.2008 ◽

2009 ◽

Vol 101 (2) ◽

pp. 773-788 ◽

Cited By ~ 57

Author(s):

Chandramouli Chandrasekaran ◽

Asif A. Ghazanfar

Keyword(s):

Spatial Scales ◽

Field Potential ◽

Superior Temporal Sulcus ◽

Gamma Band ◽

Communication Signals ◽

Frequency Bands ◽

Face To Face ◽

Natural Time ◽

Gamma Band Activity ◽

Band Activity

The integration of auditory and visual information is required for the default mode of speech–face-to-face communication. As revealed by functional magnetic resonance imaging and electrophysiological studies, the regions in and around the superior temporal sulcus (STS) are implicated in this process. To provide greater insights into the network-level dynamics of the STS during audiovisual integration, we used a macaque model system to analyze the different frequency bands of local field potential (LFP) responses to the auditory and visual components of vocalizations. These vocalizations (like human speech) have a natural time delay between the onset of visible mouth movements and the onset of the voice (the “time-to-voice” or TTV). We show that the LFP responses to faces and voices elicit distinct bands of activity in the theta (4–8 Hz), alpha (8–14 Hz), and gamma (>40 Hz) frequency ranges. Along with single neuron responses, the gamma band activity was greater for face stimuli than voice stimuli. Surprisingly, the opposite was true for the low-frequency bands—auditory responses were of a greater magnitude. Furthermore, gamma band responses in STS were sustained for dynamic faces but not so for voices (the opposite is true for auditory cortex). These data suggest that visual and auditory stimuli are processed in fundamentally different ways in the STS. Finally, we show that the three bands integrate faces and voices differently: theta band activity showed weak multisensory behavior regardless of TTV, the alpha band activity was enhanced for calls with short TTVs but showed little integration for longer TTVs, and finally, the gamma band activity was consistently enhanced for all TTVs. These data demonstrate that LFP activity from the STS can be segregated into distinct frequency bands which integrate audiovisual communication signals in an independent manner. These different bands may reflect different spatial scales of network processing during face-to-face communication.

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Modulation of high frequency by low-frequency Oscillations in the basal ganglia

10.1101/196592 ◽

2017 ◽

Author(s):

D. Nouri ◽

R. Ebrahimpour ◽

A. Mirzaei

Keyword(s):

Basal Ganglia ◽

Network Model ◽

Large Scale ◽

Low Frequency ◽

Neural Mechanisms ◽

Oscillatory Activity ◽

Beta Band ◽

Low Frequency Oscillations ◽

Delta Band ◽

Frequency Modulations

AbstractModulation of beta band fioscillatory activity (15-30 Hz) by delta band oscillatory activity (1-3 Hz) in the cortico-basal ganglia loop is important for normal basal ganglia functions. However, the neural mechanisms underlying this modulation are poorly understood. To understand the mechanisms underlying such frequency modulations in the basal ganglia, we use large scale subthalamo-pallidal network model stimulated via a delta-frequency input signal. We show that inhibition of external Globus Pallidus (GPe) and excitation of the Subthalamic nucleus (STN) using the delta-band stimulation leads to the same delta-beta interactions in the network model as the experimental results observed in healthy basal ganglia. In addition, we show that pathological beta oscillations in the network model decorrelates the delta-beta link in the network model. In general, using our simulation results, we propose that striato-pallidal inhibition and cortico-subthalamic excitation are the potential sources of the delta-beta link observed in the intact basal ganglia.

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Modeling the hemodynamic response function using EEG-fMRI data during eyes-open resting-state conditions and motor task execution

10.1101/2020.06.29.178483 ◽

2020 ◽

Author(s):

Prokopis C. Prokopiou ◽

Alba Xifra-Porxas ◽

Michalis Kassinopoulos ◽

Marie-Hélène Boudrias ◽

Georgios D. Mitsis

Keyword(s):

Response Function ◽

Resting State ◽

Motor Task ◽

Field Potential ◽

Hemodynamic Response ◽

Bold Signal ◽

Hemodynamic Response Function ◽

Beta Band ◽

Experimental Conditions ◽

Frequency Bands

AbstractIn this work, we investigated the regional characteristics of the dynamic interactions between oscillatory sources of ongoing neural activity obtained using electrophysiological recordings and the corresponding changes in the BOLD signal using simultaneous EEG-fMRI measurements acquired during a motor task, as well as under resting conditions. We casted this problem within a system-theoretic framework, where we initially performed distributed EEG source space reconstruction and subsequently employed block-structured linear and non-linear models to predict the BOLD signal from the instantaneous power in narrow frequency bands of the source local field potential (LFP) spectrum (<100 Hz). Our results suggest that the dynamics of the BOLD signal can be sufficiently described as the convolution between a linear combination of the power profile within individual frequency bands with a hemodynamic response function (HRF). During the motor task, BOLD signal variance was mainly explained by the EEG oscillations in the beta band. On the other hand, during resting-state all frequency bands of EEG exhibited significant contributions to BOLD signal variance. Moreover, the contribution of each band was found to be region specific. Our results also revealed considerable variability of the HRF across different brain regions. Specifically, sensory-motor cortices exhibited positive HRF shapes, whereas parietal and occipital cortices exhibited negative HRF shapes under both experimental conditions.

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An Olfacto-Hippocampal Network Is Dynamically Involved in Odor-Discrimination Learning

Journal of Neurophysiology ◽

10.1152/jn.00524.2007 ◽

2007 ◽

Vol 98 (4) ◽

pp. 2196-2205 ◽

Cited By ~ 95

Author(s):

Claire Martin ◽

Jennifer Beshel ◽

Leslie M. Kay

Keyword(s):

Discrimination Learning ◽

Local Field ◽

Memory Consolidation ◽

Olfactory System ◽

Field Potential ◽

Ventral Hippocampus ◽

Odor Discrimination ◽

Oscillatory Activity ◽

Beta Band ◽

Odor Learning

Several studies have shown that memory consolidation relies partly on interactions between sensory and limbic areas. The functional loop formed by the olfactory system and the hippocampus represents an experimentally tractable model that can provide insight into this question. It had been shown previously that odor-learning associated beta band oscillations (15–30 Hz) of the local field potential in the rat olfactory system are enhanced with criterion performance, but it was unknown if these involve networks beyond the olfactory system. We recorded local field potentials from the olfactory bulb (OB) and dorsal and ventral hippocampus during acquisition of odor discriminations in a go/no-go task. These regions showed increased beta oscillation power during odor sampling, accompanied by a coherence increase in this frequency band between the OB and both hippocampal subfields. This coherence between the OB and the hippocampus increased with the onset of the first rule transfer to a new odor set and remained high for all learning phases and subsequent odor sets. However, coherence between the two hippocampal fields reset to baseline levels with each new odor set and increased again with criterion performance. These data support hippocampal involvement in the network underlying odor-discrimination learning and also suggest that cooperation between the dorsal and ventral hippocampus varies with learning progress. Oscillatory activity in the beta range may thus provide a mechanism by which these areas are linked during memory consolidation, similar to proposed roles of beta oscillations in other systems with long-range connections.

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Neuromagnetic Beta-Band Oscillations during Motor Imitation in Youth with Autism

Autism Research and Treatment ◽

10.1155/2018/9035793 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

I. Buard ◽

E. Kronberg ◽

S. Steinmetz ◽

S. Hepburn ◽

D. C. Rojas

Keyword(s):

Oscillatory Activity ◽

Fine Motor ◽

Typically Developing ◽

Beta Band ◽

Motor Impairments ◽

Cortical Oscillations ◽

Cortical Rhythms ◽

Motor Imitation ◽

Age Related ◽

Adults With Asd

Children with ASD often exhibit early difficulties with action imitation, possibly due to low-level sensory or motor impairments. Impaired cortical rhythms have been demonstrated in adults with ASD during motor imitation. While those oscillations reflect an age-dependent process, they have not been fully investigated in youth with ASD. We collected magnetoencephalography data to examine patterns of oscillatory activity in the mu (8-13 Hz) and beta frequency (15-30 Hz) range in 14 adolescents with and 14 adolescents without ASD during a fine motor imitation task. Typically developing adolescents exhibited adult-like patterns of motor signals, e.g., event-related beta and mu desynchronization (ERD) before and during the movement and a postmovement beta rebound (PMBR) after the movement. In contrast, those with ASD exhibited stronger beta and mu-ERD and reduced PMBR. Behavioral performance was similar between groups despite differences in motor cortical oscillations. Finally, we observed age-related increases in PBMR and beta-ERD in the typically developing children, but this correlation was not present in the autism group. These results suggest reduced inhibitory drive in cortical rhythms in youth with autism during intact motor imitation. Furthermore, impairments in motor brain signals in autism may not be due to delayed brain development. In the context of the excitation-inhibition imbalance perspectives of autism, we offer new insights into altered organization of neurophysiological networks.

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The Generation and Modulation of Distinct Gamma Oscillations with Local, Horizontal, and Feedback Connections in the Primary Visual Cortex: A Model Study on Large-Scale Networks

Neural Plasticity ◽

10.1155/2021/8874516 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Chuanliang Han ◽

Tian Wang ◽

Yujie Wu ◽

Yang Li ◽

Yi Yang ◽

...

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Information Integration ◽

Large Scale ◽

Spatial Scales ◽

Field Potential ◽

Gamma Oscillations ◽

Gamma Oscillation ◽

Response Property ◽

The Brain

Gamma oscillation (GAMMA) in the local field potential (LFP) is a synchronized activity commonly found in many brain regions, and it has been thought as a functional signature of network connectivity in the brain, which plays important roles in information processing. Studies have shown that the response property of GAMMA is related to neural interaction through local recurrent connections (RC), feed-forward (FF), and feedback (FB) connections. However, the relationship between GAMMA and long-range horizontal connections (HC) in the brain remains unclear. Here, we aimed to understand this question in a large-scale network model for the primary visual cortex (V1). We created a computational model composed of multiple excitatory and inhibitory units with biologically plausible connectivity patterns for RC, FF, FB, and HC in V1; then, we quantitated GAMMA in network models at different strength levels of HC and other connection types. Surprisingly, we found that HC and FB, the two types of large-scale connections, play very different roles in generating and modulating GAMMA. While both FB and HC modulate a fast gamma oscillation (around 50-60 Hz) generated by FF and RC, HC generates a new GAMMA oscillating around 30 Hz, whose power and peak frequency can also be modulated by FB. Furthermore, response properties of the two GAMMAs in a network with both HC and FB are different in a way that is highly consistent with a recent experimental finding for distinct GAMMAs in macaque V1. The results suggest that distinct GAMMAs are signatures for neural connections in different spatial scales and they might be related to different functions for information integration. Our study, for the first time, pinpoints the underlying circuits for distinct GAMMAs in a mechanistic model for macaque V1, which might provide a new framework to study multiple gamma oscillations in other cortical regions.

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