Ouabain modulation of snail Br neuron bursting activity after the exposure to 10 mT static magnetic field revealed by Higuchi fractal dimension

Abstract

Abstract. Aim of this study was to investigate the application of normalized mean of the empirical Higuchi fractal dimension (FD) distributions, as a new approach to analyze the spontaneous bioelectrical activity of garden snail (Helix pomatia) Br neuron. The effect of ouabain on modulation of Br neuron bursting activity before and after the exposure to 10 mT static magnetic field (SMF) was observed by analyzing the following parameters: action potential (AP), interspike interval (ISI) and interbursting interval (IBI) components. Normalized mean of the empirical FD distributions were formed for the following experimental conditions: Control 1, Ouabain 1, Control 2, SMF 2, ASMF 2, Control 3, SMF 3 and Ouabain ASMF 3. Our main results have shown that ouabain without SMF induced increase in participation of AP and a decrease in participation of IBI components compared to the first control condition. However, in the presence of 10 mT SMF, ouabain-induced changes of measured parameters of Br neuron activity were less pronounced compared to the third control condition. We have shown that normalized mean of the empirical FD distributions is a useful method for detecting the changes in AP, ISI, and IBI components of complex bursting activity in altered physiological states.

On 2D generalization of Higuchi’s fractal dimension

“…This procedure is very useful in case of the non-stationary signal analysis, such as an electroencephalographic (EEG) and electrocorticographic (ECoG) signals or many other biomedical signals. Higuchi's method is applied using MATLAB software by Spasic that has been validated in some of our previous publications [20][21][22]25]. After many tests, our results confirm that the DF is relatively independent of the length of the window N, but much more dependent of the parameter k max .…”

“…Higuchi's method is frequently used for analysis of rat brain activity in time domain after injuries [20,21] and to comparing the brain complexity at the distinct brain levels during stable anesthesia induced by different anesthetics [22], also in monitoring the depth of anesthesia and sedation in human [23,24]. The changes of complex bursting neuronal activity in garden snail in altered physiological states have been detected by Higuchi's fractal dimension [25]. This method has been confirmed as very accurate, simple and fast to assess changes in the EEG, ECoG and neuronal activity in different experimental conditions.…”

Measures and Metrics of Biological Signals

“…Example 3.3.1 (Higuchi fractal dimension) In (Kesić et al, 2014) authors use Mean of the empirical HFD distribution to investigate the changes in the complexity of snail Br neuron activity after the treatment application. HFD measure allows fast computational tracking of variations in signals and in this study has been used in combination with the normalized mean of the empirical HFD distribution because the signal of Br neuron activity is non-stationary (Figure 3).…”

Mathematical Incorrectness of So-Called Higuchi‘s Fractal Dimension

“…Unfortunately, some published papers contain many inaccuracies and even mathematical nonsenses caused by insufficient mathematical foundations from which their authors deduce their conclusions -see [13,29,21,30,8] for example. A special group of incorrect papers are texts which deal with so called Higuchi's method or Higuchi's fractal dimension -see [29,20,17,23,32,2,22]. Research based on this incorrrect method was published even in physical [3], fractal [18] and chaos [1] journals.…”