Measuring the entropy of a neuron cell from its membrane current signal

TL;DR

This study develops modified entropy measurement methods for neuron membrane currents, successfully aligning entropy peaks with ionic equilibrium potentials, enabling analysis of cellular behavior and potential applications in disease and drug effect detection.

Contribution

The paper introduces two modifications to existing entropy measures, ensuring they peak at ionic equilibrium potentials in neuron signals, validated through logistic map simulations.

Findings

Entropy peaks align with ionic equilibrium after modifications

Modified entropy measures successfully validated with logistic map

Potential to distinguish tumor from normal cells or drug effects

Abstract

The purpose of this study was to investigate how the entropy of a neuron cell can be measured using membrane ion current signals, which were recorded from neurons in the mouse medial prefrontal cortex (mPFC). The sample entropy and the Scalogram entropy were used as entropy measurement methods. It is well known that the entropy increases in the direction of the movement of the system towards the equilibrium. Therefore, in the process of the electrical activity of a living cell, the entropy is expected to reach a maximum at the moment when the membrane potential reaches the 'Nernst equilibrium potential' (or ionic equilibrium) of the ions. However, it was observed that the entropy values obtained by traditional calculations did not reach the peak at the equilibrium state of the ions. Therefore, two modifications to these measurement methods were proposed to adjust the entropy value to the maximum at the equilibrium potential of the ions. As a result of these proposed modifications, the entropy values were observed to peak around the equilibrium potential of the ions. These refined approaches were successfully validated using the Logistic map. Additionally, the entropy results were compared with Lyapunov exponents. The results show that the behaviour of living cells can be analysed using entropy measurements. The results also suggest that the method could be used to detect differences in the behaviour of tumour and normal cells, or the effects of drugs on cells.