Primary cortical representation of sounds by the coordination of action-potential timing

@article{DeCharms1996PrimaryCR,
  title={Primary cortical representation of sounds by the coordination of action-potential timing},
  author={R. Christopher DeCharms and Michael Merzenich},
  journal={Nature},
  year={1996},
  volume={381},
  pages={610-613}
}
CORTICAL population coding could in principle rely on either the mean rate of neuronal action potentials, or the relative timing of action potentials, or both. When a single sensory stimulus drives many neurons to fire at elevated rates, the spikes of these neurons become tightly synchronized1,2, which could be involved in 'binding' together individual firing-rate feature representations into a unified object percept3. Here we demonstrate that the relative timing of cortical action potentials… 

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References

SHOWING 1-10 OF 29 REFERENCES

Dynamics of neuronal interactions in monkey cortex in relation to behavioural events

TLDR
It is shown that correlated firing between single neurons, recorded simultaneously in the frontal cortex of monkeys performing a behavioural task, evolves within a fraction of a second, and in systematic relation to behavioural events, support the notion that neurons can associate rapidly into a functional group in order to perform a computational task, at the same time becoming dissociated from concurrently activated competing groups.

Encoding of sound-source location and movement: activity of single neurons and interactions between adjacent neurons in the monkey auditory cortex.

TLDR
The data suggest that both firing rates and correlated activity between adjacent neurons in the auditory cortex encode sound location and movement, which could not have been predicted from analysis of the independent single-unit responses to the stimuli.

Sensorimotor encoding by synchronous neural ensemble activity at multiple levels of the somatosensory system.

TLDR
Multilevel synchronous activity in the rat trigeminal somatosensory system may encode not only sensory information but also the onset and temporal domain of tactile exploratory movements.

Effects of Input Synchrony on the Firing Rate of a Three-Conductance Cortical Neuron Model

TLDR
Effectiveness of synaptic transmission, measured by the peak area of cross-correlations between input and output spikes, increased with increasing synchrony, and could reduce firing rate for higher values of the three parameters.

Neural interaction in cat primary auditory cortex II. Effects of sound stimulation.

TLDR
The result suggests that the less time-consuming shift predictor-based stimulus-correction procedure can be used for cortical neurons, and that the assumption of additivity of stimulus and connectivity effects on neural synchrony is generally violated.

Oscillatory responses in cat visual cortex exhibit inter-columnar synchronization which reflects global stimulus properties

TLDR
It is demonstrated here that neurons in spatially separate columns can synchronize their oscillatory responses, which has, on average, no phase difference, depends on the spatial separation and the orientation preference of the cells and is influenced by global stimulus properties.

Dynamics of neuronal firing correlation: modulation of "effective connectivity".

TLDR
Adopting a model-based approach, this work develops procedures to quantify and properly normalize the classical joint peristimulus time scatter diagram and generalizes the classical measures for quantifying a direct interneuronal connection to include possible stimulus-locked time variations.

Modality and topographic properties of single neurons of cat's somatic sensory cortex.

TLDR
Observations upon the modality and topographical attributes of single neurons of the first somatic sensory area of the cat’s cerebral cortex, the analogue of the cortex of the postcentral gyrus in the primate brain, support an hypothesis of the functional organization of this cortical area.

Stimulus-Dependent Synchronization of Neuronal Assemblies

TLDR
The results suggest that the modulation of neuronal interactions by extended features of a stimulus may give rise to complex spatiotemporal fluctuations in the phases of neuronal oscillations.

The Effect of Synchronized Inputs at the Single Neuron Level

TLDR
The role of synaptic synchronization is investigated for the leaky integrate-and-fire neuron as well as for a biophysically and anatomically detailed compartmental model of a cortical pyramidal cell to find that if the number of excitatory inputs, N, is on the same order as thenumber of fully synchronized inputs necessary to trigger a single action potential, Nt, synchronization always increases the firing rate.