Biosignals: Measurement and analysis with applications in psychology

Presentation for the EIP 2020 paper on biosignals measurement and analysis with selected applications in psychology authored by Nadica Miljković, Olga Dubljević, Bojana Bjegojević, and Nikola Milosavljević. Presentation is prepared and presented by Nadica Miljković and Olga Dubljević. Abstract (available at http://empirijskaistrazivanja.org/en/biosignals-measurement-and-analysis-with-applications-in-psychology/): Human body functioning can be directly or indirectly assessed by measurement and analysis of biosignals. These procedures commonly result in the extraction of features i.e., biomarkers that can be further used for description or prediction of various psychological functions and processes. Biomarkers serve to provide additional validity to obtained data and to address some of the issues inherent to commonly used psychological techniques, such as self-report, behavioral, and task-performance paradigm. The benefits of including the physiological approach in psychology research include in-the-moment, automatic assessment of the subjects’ reactions, and detection of reactions when no change in behavior or task performance can be observed. The most commonly used measures in psychology are heart rate (HR), heart rate variability (HRV), electroencephalogram (EEG), galvanic skin response (GSR), respiration, jaw-clenching, eye movements and blink interval (measured for example with electromyography – EMG and electrooculography – EOG). Due to the intricate nature of biosignals, measurement and analysis can be rather complex. Biosignals have commonly small signal-to-noise ratio i.e., can be vastly affected by external and internal artifacts, and persons’ physiological response(s) are compound in nature and can be influenced by a relatively large number of factors which can make feature extraction diligent or even impossible. Therefore, appropriate procedures for measurement and analysis must be carefully considered and precisely followed. For example, simple electrophysiology measurement can be affected by numerous factors, like skin-electrode impedance, electrode placement, physiological cross-talk (e.g., interference with other physiological signals), cable movements, power hum, etc. To design appropriate protocols for biosignal application in psychology, close collaboration between biomedical engineers and psychologists is a prerequisite for successful scientific study. We present an overview of biosignal-based assessment procedures with selected examples from applications in psychology. Additionally, we discuss how these biomarkers reflect changes in the sympathetic and parasympathetic nervous system activation, and how they should be used in psychological research. A possible implementation of biomarkers in studies assessing emotional and cognitive load will be presented