Journal Article

Temporal whitening by power-law adaptation in neocortical neurons

Naud, Richard, Pozzorini, Christian, Mensi, Skander, Gerstner, Wulfram

2013

Overview

Using a combination of computational modeling and electrophysiological recordings, the authors show that the dynamics of spike-frequency adaptation have the effect of temporally decorrelating incoming signals. This decorrelation makes for more energy-efficient information transfer in the CNS. Spike-frequency adaptation (SFA) is widespread in the CNS, but its function remains unclear. In neocortical pyramidal neurons, adaptation manifests itself by an increase in the firing threshold and by adaptation currents triggered after each spike. Combining electrophysiological recordings in mice with modeling, we found that these adaptation processes lasted for more than 20 s and decayed over multiple timescales according to a power law. The power-law decay associated with adaptation mirrored and canceled the temporal correlations of input current received in vivo at the somata of layer 2/3 somatosensory pyramidal neurons. These findings suggest that, in the cortex, SFA causes temporal decorrelation of output spikes (temporal whitening), an energy-efficient coding procedure that, at high signal-to-noise ratio, improves the information transfer.

• Publisher: Nature Publishing Group US,Nature Publishing Group
• Subject: 631/378/116/2395 / Action Potentials - physiology / Adaptation / Adaptation (Physiology) / Adaptation, Physiological - physiology / Animal Genetics and Genomics / Animals / Animals, Newborn / Behavioral Sciences / Biological Techniques / Biomedicine / Biophysics / Codes / Electric Stimulation / In Vitro Techniques / Mice / Mice, Inbred C57BL / Models, Neurological / Models, Structural / Neocortex / Neocortex - cytology / Neurobiology / Neurons / Neurosciences / Patch-Clamp Techniques / Physiological aspects / Pyramidal Cells - physiology / Signal to noise ratio / Threshold (Perception)