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High baseline activity in inferior temporal cortex improves neural and behavioral discriminability during visual categorization.

Emadi N, Rajimehr R, Esteky H - Front Syst Neurosci (2014)

Bottom Line: However, it is not known how the baseline activity contributes to neural coding and behavior.Specifically we found that a low-frequency (<8 Hz) oscillation in the spike train, prior and phase-locked to the stimulus onset, was correlated with increased gamma power and neuronal baseline activity.This enhancement of the baseline activity was then followed by an increase in the neural selectivity and the response reliability and eventually a higher behavioral performance.

View Article: PubMed Central - PubMed

Affiliation: School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM) Tehran, Iran ; Research Center for Brain and Cognition, School of Medicine, University of Shahid Beheshti Tehran, Iran ; Howard Hughes Medical Institute and Department of Neurobiology, Stanford University School of Medicine Stanford, CA, USA.

ABSTRACT
Spontaneous firing is a ubiquitous property of neural activity in the brain. Recent literature suggests that this baseline activity plays a key role in perception. However, it is not known how the baseline activity contributes to neural coding and behavior. Here, by recording from the single neurons in the inferior temporal cortex of monkeys performing a visual categorization task, we thoroughly explored the relationship between baseline activity, the evoked response, and behavior. Specifically we found that a low-frequency (<8 Hz) oscillation in the spike train, prior and phase-locked to the stimulus onset, was correlated with increased gamma power and neuronal baseline activity. This enhancement of the baseline activity was then followed by an increase in the neural selectivity and the response reliability and eventually a higher behavioral performance.

No MeSH data available.


Relationship between different events in the preceding trial and the baseline airing rate in the following trial. The baseline firing rates were compared between different conditions of the last trial: a body or a non-body image was presented (A), a high-noise (90 and 70%) or low-noise (55 and 40%) image was presented (B), a body or a non-body choice was made by the monkey (C), a correct or a wrong choice was made by the monkey (D). Each data point shows the one body neuron.
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Figure 7: Relationship between different events in the preceding trial and the baseline airing rate in the following trial. The baseline firing rates were compared between different conditions of the last trial: a body or a non-body image was presented (A), a high-noise (90 and 70%) or low-noise (55 and 40%) image was presented (B), a body or a non-body choice was made by the monkey (C), a correct or a wrong choice was made by the monkey (D). Each data point shows the one body neuron.

Mentions: The baseline activity in a given trial could be potentially modulated by various events in a preceding trial. To test this, trials were divided into two groups based on a particular event in the preceding trial, then the baseline firing rates in these two groups were compared. We did this analysis for the following conditions: (1) the image in the preceding trial was a body or a non-body (Figure 7A, t-test, P = 0.7), (2) the image in the preceding trial was a low-noise image (90 or 70% noise levels) or a high-noise image (55 or 40% noise levels) (Figure 7B, t-test, P = 0.2), (3) the monkey's choice in the preceding trial was a body choice or a non-body choice (Figure 7C, t-test, P = 0.16), (4) the monkey's response in the preceding trial was a correct response (“reward” condition) or a wrong response (“no reward” condition) (Figure 7D, t-test, P = 0.4). The results showed no significant modulation of the baseline firing rate by different events in the preceding trial.


High baseline activity in inferior temporal cortex improves neural and behavioral discriminability during visual categorization.

Emadi N, Rajimehr R, Esteky H - Front Syst Neurosci (2014)

Relationship between different events in the preceding trial and the baseline airing rate in the following trial. The baseline firing rates were compared between different conditions of the last trial: a body or a non-body image was presented (A), a high-noise (90 and 70%) or low-noise (55 and 40%) image was presented (B), a body or a non-body choice was made by the monkey (C), a correct or a wrong choice was made by the monkey (D). Each data point shows the one body neuron.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4217374&req=5

Figure 7: Relationship between different events in the preceding trial and the baseline airing rate in the following trial. The baseline firing rates were compared between different conditions of the last trial: a body or a non-body image was presented (A), a high-noise (90 and 70%) or low-noise (55 and 40%) image was presented (B), a body or a non-body choice was made by the monkey (C), a correct or a wrong choice was made by the monkey (D). Each data point shows the one body neuron.
Mentions: The baseline activity in a given trial could be potentially modulated by various events in a preceding trial. To test this, trials were divided into two groups based on a particular event in the preceding trial, then the baseline firing rates in these two groups were compared. We did this analysis for the following conditions: (1) the image in the preceding trial was a body or a non-body (Figure 7A, t-test, P = 0.7), (2) the image in the preceding trial was a low-noise image (90 or 70% noise levels) or a high-noise image (55 or 40% noise levels) (Figure 7B, t-test, P = 0.2), (3) the monkey's choice in the preceding trial was a body choice or a non-body choice (Figure 7C, t-test, P = 0.16), (4) the monkey's response in the preceding trial was a correct response (“reward” condition) or a wrong response (“no reward” condition) (Figure 7D, t-test, P = 0.4). The results showed no significant modulation of the baseline firing rate by different events in the preceding trial.

Bottom Line: However, it is not known how the baseline activity contributes to neural coding and behavior.Specifically we found that a low-frequency (<8 Hz) oscillation in the spike train, prior and phase-locked to the stimulus onset, was correlated with increased gamma power and neuronal baseline activity.This enhancement of the baseline activity was then followed by an increase in the neural selectivity and the response reliability and eventually a higher behavioral performance.

View Article: PubMed Central - PubMed

Affiliation: School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM) Tehran, Iran ; Research Center for Brain and Cognition, School of Medicine, University of Shahid Beheshti Tehran, Iran ; Howard Hughes Medical Institute and Department of Neurobiology, Stanford University School of Medicine Stanford, CA, USA.

ABSTRACT
Spontaneous firing is a ubiquitous property of neural activity in the brain. Recent literature suggests that this baseline activity plays a key role in perception. However, it is not known how the baseline activity contributes to neural coding and behavior. Here, by recording from the single neurons in the inferior temporal cortex of monkeys performing a visual categorization task, we thoroughly explored the relationship between baseline activity, the evoked response, and behavior. Specifically we found that a low-frequency (<8 Hz) oscillation in the spike train, prior and phase-locked to the stimulus onset, was correlated with increased gamma power and neuronal baseline activity. This enhancement of the baseline activity was then followed by an increase in the neural selectivity and the response reliability and eventually a higher behavioral performance.

No MeSH data available.