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Modulation of temporal precision in thalamic population responses to natural visual stimuli.

Desbordes G, Jin J, Alonso JM, Stanley GB - Front Syst Neurosci (2010)

Bottom Line: In response to natural scene stimuli, neurons in the lateral geniculate nucleus (LGN) are temporally precise - on a time scale of 10-25 ms - both within single cells and across cells within a population.This time scale, established by non stimulus-driven elements of neuronal firing, is significantly shorter than that of natural scenes, yet is critical for the neural representation of the spatial and temporal structure of the scene.Given the sensitivity of the thalamocortical synapse to closely timed spikes and the importance of fine timing precision for the faithful representation of natural scenes, the modulation of thalamic population timing over these time scales is likely important for cortical representations of the dynamic natural visual environment.

View Article: PubMed Central - PubMed

Affiliation: Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University Atlanta, GA, USA.

ABSTRACT
Natural visual stimuli have highly structured spatial and temporal properties which influence the way visual information is encoded in the visual pathway. In response to natural scene stimuli, neurons in the lateral geniculate nucleus (LGN) are temporally precise - on a time scale of 10-25 ms - both within single cells and across cells within a population. This time scale, established by non stimulus-driven elements of neuronal firing, is significantly shorter than that of natural scenes, yet is critical for the neural representation of the spatial and temporal structure of the scene. Here, a generalized linear model (GLM) that combines stimulus-driven elements with spike-history dependence associated with intrinsic cellular dynamics is shown to predict the fine timing precision of LGN responses to natural scene stimuli, the corresponding correlation structure across nearby neurons in the population, and the continuous modulation of spike timing precision and latency across neurons. A single model captured the experimentally observed neural response, across different levels of contrasts and different classes of visual stimuli, through interactions between the stimulus correlation structure and the nonlinearity in spike generation and spike history dependence. Given the sensitivity of the thalamocortical synapse to closely timed spikes and the importance of fine timing precision for the faithful representation of natural scenes, the modulation of thalamic population timing over these time scales is likely important for cortical representations of the dynamic natural visual environment.

No MeSH data available.


Related in: MedlinePlus

The generalized linear model (GLM). See “Materials and Methods” for details.
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Figure 2: The generalized linear model (GLM). See “Materials and Methods” for details.

Mentions: Figure 2 shows the model framework, which transforms the visual input (in the form of a spatiotemporal signal) into a series of spikes. The visual stimulus is first passed through a spatiotemporal filter corresponding to the classical receptive field of the neuron, which yields a temporal signal that we refer to as the filtered stimulus. This signal is then passed through a static exponential nonlinearity, resulting in the conditional intensity function which drives the Poisson spike generator. In the absence of spike-history dependence, the model reduces to the classical linear non-linear Poisson (LNP) model structure (Chichilnisky, 2001; Dayan and Abbott, 2001). In the full GLM, however, each generated spike is fed back through a spike history temporal filter and sums with the filtered stimulus, thereby modifying the conditional intensity function and potentially influencing the probability of future spiking. See Methods for more details on the model structure and fitting procedure.


Modulation of temporal precision in thalamic population responses to natural visual stimuli.

Desbordes G, Jin J, Alonso JM, Stanley GB - Front Syst Neurosci (2010)

The generalized linear model (GLM). See “Materials and Methods” for details.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2992450&req=5

Figure 2: The generalized linear model (GLM). See “Materials and Methods” for details.
Mentions: Figure 2 shows the model framework, which transforms the visual input (in the form of a spatiotemporal signal) into a series of spikes. The visual stimulus is first passed through a spatiotemporal filter corresponding to the classical receptive field of the neuron, which yields a temporal signal that we refer to as the filtered stimulus. This signal is then passed through a static exponential nonlinearity, resulting in the conditional intensity function which drives the Poisson spike generator. In the absence of spike-history dependence, the model reduces to the classical linear non-linear Poisson (LNP) model structure (Chichilnisky, 2001; Dayan and Abbott, 2001). In the full GLM, however, each generated spike is fed back through a spike history temporal filter and sums with the filtered stimulus, thereby modifying the conditional intensity function and potentially influencing the probability of future spiking. See Methods for more details on the model structure and fitting procedure.

Bottom Line: In response to natural scene stimuli, neurons in the lateral geniculate nucleus (LGN) are temporally precise - on a time scale of 10-25 ms - both within single cells and across cells within a population.This time scale, established by non stimulus-driven elements of neuronal firing, is significantly shorter than that of natural scenes, yet is critical for the neural representation of the spatial and temporal structure of the scene.Given the sensitivity of the thalamocortical synapse to closely timed spikes and the importance of fine timing precision for the faithful representation of natural scenes, the modulation of thalamic population timing over these time scales is likely important for cortical representations of the dynamic natural visual environment.

View Article: PubMed Central - PubMed

Affiliation: Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University Atlanta, GA, USA.

ABSTRACT
Natural visual stimuli have highly structured spatial and temporal properties which influence the way visual information is encoded in the visual pathway. In response to natural scene stimuli, neurons in the lateral geniculate nucleus (LGN) are temporally precise - on a time scale of 10-25 ms - both within single cells and across cells within a population. This time scale, established by non stimulus-driven elements of neuronal firing, is significantly shorter than that of natural scenes, yet is critical for the neural representation of the spatial and temporal structure of the scene. Here, a generalized linear model (GLM) that combines stimulus-driven elements with spike-history dependence associated with intrinsic cellular dynamics is shown to predict the fine timing precision of LGN responses to natural scene stimuli, the corresponding correlation structure across nearby neurons in the population, and the continuous modulation of spike timing precision and latency across neurons. A single model captured the experimentally observed neural response, across different levels of contrasts and different classes of visual stimuli, through interactions between the stimulus correlation structure and the nonlinearity in spike generation and spike history dependence. Given the sensitivity of the thalamocortical synapse to closely timed spikes and the importance of fine timing precision for the faithful representation of natural scenes, the modulation of thalamic population timing over these time scales is likely important for cortical representations of the dynamic natural visual environment.

No MeSH data available.


Related in: MedlinePlus