Stimuli of varying spatial scale induce gamma activity with distinct temporal characteristics in human visual cortex

  title={Stimuli of varying spatial scale induce gamma activity with distinct temporal characteristics in human visual cortex},
  author={Avgis Hadjipapas and Peyman Adjamian and Jennifer B. Swettenham and Ian E. Holliday and Gareth R. Barnes},
Spectral properties of induced and evoked gamma oscillations in human early visual cortex to moving and stationary stimuli.
It is suggested that early visual areas encode moving and stationary percepts via activity at higher and lower gamma frequencies, respectively.
Linear Tuning of Gamma Amplitude and Frequency to Luminance Contrast: Evidence from a Continuous Mapping Paradigm
Both gamma amplitude and frequency were linearly modulated by stimulus contrast, but that the gain of this modulation varied across individuals, suggesting that these may be independent traits driven by distinct neurophysiological processes.
Induced Gamma activity in primary visual cortex is related to luminance and not color contrast: An MEG study.
This work showed that induced gamma activity is maximal in response to gratings of 3 cycles per degree (3 cpd) of high luminance contrast, and examined stimulus contrast further by using isoluminant red/green gratings that possess color but not Luminance contrast using the same cohort of subjects.
Visual stimulus eccentricity affects human gamma peak frequency
BOLD Responses in Human Primary Visual Cortex are Insensitive to Substantial Changes in Neural Activity
The relationship between blood oxygenation level dependent-functional magnetic resonance imaging (BOLD-fMRI) and magnetoencephalography (MEG) metrics were explored using low-level visual stimuli known to elicit a rich variety of neural responses, providing further evidence that the relationship between the fMRI-BOLD response and cortical neural activity is complex.
Synchronization Dynamics in Response to Plaid Stimuli in Monkey V1
The results suggest that the functional architecture of the cortex is a major determinant of the neuronal synchronization dynamics in V1, and may be that single gratings induce strong cooperative interactions among populations of cells that share similar response properties, whereas plaids lead to competition.


Rapid feature selective neuronal synchronization through correlated latency shifting
It is shown that neuron pairs in cat primary visual cortex exhibited correlated fluctuations in response latency, particularly when they had overlapping receptive fields or similar orientation preferences, which may be important in early visual processes.
LFP power spectra in V1 cortex: the graded effect of stimulus contrast.
The temporal/spectral structures of the LFP located in the gamma band-which become most evident at the highest contrasts-provide additional constraints on potential mechanisms underlying the stimulus response properties of spiking neurons in V1.
Induced visual illusions and gamma oscillations in human primary visual cortex
It is hypothesize that the intrinsic properties of gamma oscillations may underlie visual discomfort and play a role in the onset of seizures.
Different frequencies for different scales of cortical integration: from local gamma to long range alpha/theta synchronization.
  • A. von Stein, J. Sarnthein
  • Biology, Psychology
    International journal of psychophysiology : official journal of the International Organization of Psychophysiology
  • 2000
Oscillatory Neuronal Synchronization in Primary Visual Cortex as a Correlate of Stimulus Selection
It is hypothesize that enhanced gamma-frequency synchronization in primary visual cortex is a correlate of stimulus selection and is likely to be translated into firing rate changes at later processing stages.
Task-Related Changes in Cortical Synchronization Are Spatially Coincident with the Hemodynamic Response
This study demonstrates how SAM, spatial normalization, and intersubject averaging enable group MEG studies to be performed and represents an important advance in the use of MEG as a cognitive neuroimaging technique and also allows mutual cross-validation with fMRI.
Spatial-frequency organization in primate striate cortex.
There is a systematic correlation between the topographical variation in spatial-frequency tuning and the modular CytOx pattern, which varied continuously in density, and low-frequency cells are at the center of the blobs, and cells tuned to increasingly higher spatial frequencies are at increasing radial distances.
Synchronization of neurons during local field potential oscillations in sensorimotor cortex of awake monkeys.
The neural activity associated with 20- to 40-Hz oscillations in sensorimotor cortex of awake monkeys was investigated by recording action potentials of single and multiple units to suggest units across wide regions can become transiently synchronized specifically during LFP oscillations.