Limits...
Temporal decorrelation by SK channels enables efficient neural coding and perception of natural stimuli.

Huang CG, Zhang ZD, Chacron MJ - Nat Commun (2016)

Bottom Line: However, the mechanisms by which such efficient processing is achieved, and the consequences for perception and behaviour remain poorly understood.Specifically, these channels allow for the high-pass filtering of sensory input, thereby removing temporal correlations or, equivalently, whitening frequency response power.Our results thus demonstrate a novel mechanism by which the nervous system can implement efficient processing and perception of natural sensory input that is likely to be shared across systems and species.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, McGill University, 3655 Sir William Osler, Montreal, Quebec, Canada H3G 1Y6.

ABSTRACT
It is commonly assumed that neural systems efficiently process natural sensory input. However, the mechanisms by which such efficient processing is achieved, and the consequences for perception and behaviour remain poorly understood. Here we show that small conductance calcium-activated potassium (SK) channels enable efficient neural processing and perception of natural stimuli. Specifically, these channels allow for the high-pass filtering of sensory input, thereby removing temporal correlations or, equivalently, whitening frequency response power. Varying the degree of adaptation through pharmacological manipulation of SK channels reduced efficiency of coding of natural stimuli, which in turn gave rise to predictable changes in behavioural responses that were no longer matched to natural stimulus statistics. Our results thus demonstrate a novel mechanism by which the nervous system can implement efficient processing and perception of natural sensory input that is likely to be shared across systems and species.

No MeSH data available.


Weakly electric fish display behavioral responses that are matched to natural stimulus statistics.(a) Schematic representation showing the behavioural setup in which the animal's behavioural responses to stimuli are recorded by continuously monitoring its EOD, whose spectrogram indicates the time-varying frequency. (b) Stimulus (blue) and time-varying EOD frequency responses (green) to 0.05 Hz (middle) and 0.75 Hz (bottom) sinusoidal stimuli. Note the smaller changes in EOD frequency in response to the 0.75 Hz stimulus (vertical green arrows). (c) Behavioural response sensitivity (green) is matched to the power spectrum (blue) of natural envelope stimuli. Inset: population-averaged power-law exponents from behavioural sensitivity (green) and from natural envelope stimuli (blue).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4837484&req=5

f7: Weakly electric fish display behavioral responses that are matched to natural stimulus statistics.(a) Schematic representation showing the behavioural setup in which the animal's behavioural responses to stimuli are recorded by continuously monitoring its EOD, whose spectrogram indicates the time-varying frequency. (b) Stimulus (blue) and time-varying EOD frequency responses (green) to 0.05 Hz (middle) and 0.75 Hz (bottom) sinusoidal stimuli. Note the smaller changes in EOD frequency in response to the 0.75 Hz stimulus (vertical green arrows). (c) Behavioural response sensitivity (green) is matched to the power spectrum (blue) of natural envelope stimuli. Inset: population-averaged power-law exponents from behavioural sensitivity (green) and from natural envelope stimuli (blue).

Mentions: Information transmitted by neurons is only useful to an organism if it is actually decoded downstream. Thus, we next investigated how efficient coding of natural stimuli by ELL pyramidal neurons mediates perception. To do so, we took advantage of the fact that weakly electric fish display robust behavioural responses to envelope stimuli1831 (Fig. 7a). These consist of changes in the animal's EOD frequency that follows the stimulus' detailed timecourse but whose magnitude decreases with increasing frequency (Fig. 7b). Behavioural response sensitivity is matched to natural stimulus power (Fig. 7c). Indeed, both curves decreased as a power law with exponents αbehaviour and αstim that were not significantly different from one another (Fig. 7c, inset). This matching ensures that behavioural sensitivity is greatest for stimulus frequencies that tend to occur most frequently in the natural environment418.


Temporal decorrelation by SK channels enables efficient neural coding and perception of natural stimuli.

Huang CG, Zhang ZD, Chacron MJ - Nat Commun (2016)

Weakly electric fish display behavioral responses that are matched to natural stimulus statistics.(a) Schematic representation showing the behavioural setup in which the animal's behavioural responses to stimuli are recorded by continuously monitoring its EOD, whose spectrogram indicates the time-varying frequency. (b) Stimulus (blue) and time-varying EOD frequency responses (green) to 0.05 Hz (middle) and 0.75 Hz (bottom) sinusoidal stimuli. Note the smaller changes in EOD frequency in response to the 0.75 Hz stimulus (vertical green arrows). (c) Behavioural response sensitivity (green) is matched to the power spectrum (blue) of natural envelope stimuli. Inset: population-averaged power-law exponents from behavioural sensitivity (green) and from natural envelope stimuli (blue).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4837484&req=5

f7: Weakly electric fish display behavioral responses that are matched to natural stimulus statistics.(a) Schematic representation showing the behavioural setup in which the animal's behavioural responses to stimuli are recorded by continuously monitoring its EOD, whose spectrogram indicates the time-varying frequency. (b) Stimulus (blue) and time-varying EOD frequency responses (green) to 0.05 Hz (middle) and 0.75 Hz (bottom) sinusoidal stimuli. Note the smaller changes in EOD frequency in response to the 0.75 Hz stimulus (vertical green arrows). (c) Behavioural response sensitivity (green) is matched to the power spectrum (blue) of natural envelope stimuli. Inset: population-averaged power-law exponents from behavioural sensitivity (green) and from natural envelope stimuli (blue).
Mentions: Information transmitted by neurons is only useful to an organism if it is actually decoded downstream. Thus, we next investigated how efficient coding of natural stimuli by ELL pyramidal neurons mediates perception. To do so, we took advantage of the fact that weakly electric fish display robust behavioural responses to envelope stimuli1831 (Fig. 7a). These consist of changes in the animal's EOD frequency that follows the stimulus' detailed timecourse but whose magnitude decreases with increasing frequency (Fig. 7b). Behavioural response sensitivity is matched to natural stimulus power (Fig. 7c). Indeed, both curves decreased as a power law with exponents αbehaviour and αstim that were not significantly different from one another (Fig. 7c, inset). This matching ensures that behavioural sensitivity is greatest for stimulus frequencies that tend to occur most frequently in the natural environment418.

Bottom Line: However, the mechanisms by which such efficient processing is achieved, and the consequences for perception and behaviour remain poorly understood.Specifically, these channels allow for the high-pass filtering of sensory input, thereby removing temporal correlations or, equivalently, whitening frequency response power.Our results thus demonstrate a novel mechanism by which the nervous system can implement efficient processing and perception of natural sensory input that is likely to be shared across systems and species.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, McGill University, 3655 Sir William Osler, Montreal, Quebec, Canada H3G 1Y6.

ABSTRACT
It is commonly assumed that neural systems efficiently process natural sensory input. However, the mechanisms by which such efficient processing is achieved, and the consequences for perception and behaviour remain poorly understood. Here we show that small conductance calcium-activated potassium (SK) channels enable efficient neural processing and perception of natural stimuli. Specifically, these channels allow for the high-pass filtering of sensory input, thereby removing temporal correlations or, equivalently, whitening frequency response power. Varying the degree of adaptation through pharmacological manipulation of SK channels reduced efficiency of coding of natural stimuli, which in turn gave rise to predictable changes in behavioural responses that were no longer matched to natural stimulus statistics. Our results thus demonstrate a novel mechanism by which the nervous system can implement efficient processing and perception of natural sensory input that is likely to be shared across systems and species.

No MeSH data available.