Analysis of EEG and ECG time series in response to olfactory and Cognitive tasks

Abstract

The human body can be viewed as a collection of distinct subsystems called organs that work together to execute a specific function. Even though a comprehensive understanding of the relationship between the structural and functional links between various organs appears impossible, unravelling the inter-organ dependence could be used as a risk predictor in many instances of pathological conditions. The purpose of this study is to comprehend the interactions between the heart and brain stimulated by the sense of smell (natural whole cinnamon, green chilli, crushed pepper, and camphor) while performing cognitive tasks. Permutation entropy was used to extract the measure of variability in the information contained in the EEG and ECG signals, which served as the basis for understanding the highly correlated behaviour of the heart and brain. As per the findings, there was a significant correlation between the recorded EEG and ECG signals under various conditions, including state of rest, presence of olfactory stimuli, cognitive task and aromatherapy. The individual's engagement during cognitive activities was found by computing the coefficient of similarity between the recorded ECG signal and, the EEG signals obtained from the right and the left frontal regions of the brain measured using the Eight-channel EEG head band. The heart rate variability (HRV) from the ECG signal and the power contained in the individual frequency regions of the EEG signal were used as indicators of cognitive task engagement and relaxation during aromatherapy. These findings may be beneficial for selecting the appropriate olfactory stimuli for maintaining a healthy mental state, whether cognitive or relaxing and sleep conditioning.