Auditory Stimuli Coding by Postsynaptic Potential and Local Field Potential Features

Abstract

The relation between physical stimuli and neurophysiological responses, such as action potentials (spikes) and Local Field Potentials (LFP), has recently been experimented in order to explain how neurons encode auditory information. However, none of these experiments presented analyses with postsynaptic potentials (PSPs). In the present study, we have estimated information values between auditory stimuli and amplitudes/latencies of PSPs and LFPs in anesthetized rats in vivo. To obtain these values, a new method of information estimation was used. This method produced more accurate estimates than those obtained by using the traditional binning method; a fact that was corroborated by simulated data. The traditional binning method could not certainly impart such accuracy even when adjusted by quadratic extrapolation. We found that the information obtained from LFP amplitude variation was significantly greater than the information obtained from PSP amplitude variation. This confirms the fact that LFP reflects the action of many PSPs. Results have shown that the auditory cortex codes more information of stimuli frequency with slow oscillations in groups of neurons than it does with slow oscillations in neurons separately.

Estimation of Directed Information to Processes Assuming Continuous Values with CTW Algorithm

“…Discretization methods are often used in the estimation of mutual information between two continuous-valued random variables [13]. Even though the discretization may lead to biased estimates [14], they are very appealing due to its simplicity.…”

Estimation of Transfer Entropy between Discrete and Continuous Random Processes

“…Ross estimator has been indicated as more efficient than popular binning estimator, even when binning is applied with bias correction [26]. In order to understand Ross estimator, consider the identity [20] …”

Earliest Experience of a Relatively Rare Sound But Not a Frequent Sound Causes Long-Term Changes in the Adult Auditory Cortex

“…We next performed extracellular recordings in the mouse before ECO (P7-P12) from the ACX SPNs and L4 simultaneously with custom-made staggered electrodes arrays (4 Â 4 arrays x-y spacing 125 mm, 8 in SPN and 8 in L4, 400 or 600 mm apart in-depth, Microprobes for Life Sciences). Raw LFPs have been used extensively in the literature to support responses (Liu et al, 2015;De Assis et al, 2016), especially to refer to local synaptic activity in multiple species (Kafaligonul et al, 2018;Sołyga and Barkat, 2019) and multiple brain areas (Galindo-Leon and Liu, 2010;Kafaligonul et al, 2018). Sound-evoked LFPs (see Materials and Methods) simultaneously obtained from SP (!800 mm; P8-P9, N = 3 mice, responsive/total sites: 28 of 44 (63.63%) and P10-P11, N = 4 mice, responsive/total sites: 44 of 72 (61.11%) and L4 (300-350 mm, P8-P9, N = 3 mice: responsive/ total sites: 27 of 44 (61.36%) and P10-P11, N = 4 mice: responsive/total sites: 52 of 72 (72.22%) locations) before ECO showed significant sound-driven activity (Fig.…”