Real-time audio processing of real-life soundscapes for EEG analysis: ERPs based on natural sound onsets

Abstract

With smartphone-based mobile electroencephalography (EEG), we can investigate sound perception beyond the lab. To understand sound perception in the real world, we need to relate naturally occurring sounds to EEG data. For this, EEG and audio information need to be synchronized precisely, only then it is possible to capture fast and transient evoked neural responses and relate them to individual sounds. We have developed Android applications (AFEx and Record-a) that allow for the concurrent acquisition of EEG data and audio features, i.e., sound onsets, average signal power (RMS) and power spectral density (PSD) on smartphone. In this paper, we evaluate these apps by computing event-related potentials (ERPs) evoked by everyday sounds. One participant listened to piano notes (played live by a pianist) and to a home-office soundscape. Timing tests showed that the temporal precision of the system is very good. We calculated ERPs to sound onsets and observed the typical P1-N1-P2 complex of auditory processing. Furthermore, we show how to relate information on loudness (RMS) and spectra (PSD) to brain activity. In future studies, we can use this system to study sound processing in everyday life.

Investigating the attentional focus to workplace-related soundscapes in a complex audio-visual-motor task using EEG

“…We showed that meaningful EEG responses can be measured in a complex soundscape. In a following step, we suggest to use smartphone-based technology that enables the simultaneous recording of EEG and audio features in a data protected way (Blum, Hölle, Bleichner, & Debener, 2021; Hölle, Blum, Kissner, Debener, & Bleichner, 2021), and apply it to the operating room. This way, responses to naturally occurring sounds can be measured.…”

CameraEEG: Synchronized Recording of Video with Electroencephalogram data on an Android Application

“…Unlike previous natural recording applications that seem to use multiple apps or complex setups to present/record external stimuli and EEG [2], [33], our app records them using a single mobile application with EEG device specific libraries. This setup makes it easy to reshape for specific applications and adding on additional modules and decreases the load on the mobile in comparison to using multiple applications simultaneously.…”

“…Mobile apps are applications that run on a smartphone for a specific task and recently numerous are being developed for cognitive applications. AFEx and Record-a are two apps developed for understanding sound perception in a real-world situation [2]. Multi-app framework integrated data acquisition (smarting app), BCI processing on SCALA (Signal Processing and CLassification on Android), and stimulus presentation (Stimulus Android app) on an android smartphone [5].…”