EEG alpha wave responses to sounds from neighbours in high-rise wood residential buildings

This study explored electroencephalogram (EEG) alpha waves (α-EEG) in response to neighbours’ sounds in wood residential buildings. Experiments were carried out in a laboratory to collect α-EEG data in distinct acoustics scenarios. A series of impact and airborne sounds were generated using loudspeakers and subwoofers, while the participants sat comfortably in a simulated living room wearing EEG headsets. Impact sounds were those of footsteps of adults walking on floors equipped with different timber floor configurations, whereas airborne sounds were of speech and music digitally filtered to resemble the good and poor sound insulation performances of lightweight vertical partitions. The sound sources were presented both individually and in combination (e.g. footsteps combined with music or speech). Noise sensitivity and attitudes towards neighbours were introduced as non-acoustic factors. The study highlighted significantly higher α-EEG in response to footsteps heard through floors characterised by low impact sound pressure levels (SPL) and to music heard through partition walls with low sound reduction indices. The effective duration of the autocorrelation function, τe, was computed to investigate subjective preference, and significant differences between sounds heard at various SPLs were identified for speech and music. Footsteps sounds in combination with an airborne source elicited higher α-EEG when compared to single footsteps sounds. Participants with self-reported low noise-sensitivity and positive attitude towards neighbours showed significantly larger α-EEG responses when exposed to sounds from neighbours than those who had high noise-sensitivity and negative attitude towards neighbours.