Relaxing effects of music and odors on physiological recovery after cognitive stress and unexpected absence of multisensory benefit

Abstract

Several studies have described, often separately, the relaxing effects of music or odor on the autonomic nervous system (ANS) activity. Only a few studies compared the presentation of these stimuli and their interaction within a same experimental protocol. Here, we examined whether relaxing music (slow‐paced classical pieces) and odor (lavender essential oil) either presented in isolation or in combination would facilitate physiological recovery after cognitive stress. We continuously recorded the electrocardiogram to assess the high‐frequency component of heart rate variability (HF‐HRV), an index of parasympathetic activity, and electrodermal activity (EDA), an index of sympathetic activity, 10 min before, during and 30 min after a cognitive stress (i.e., completing timely constrained cognitively demanding tasks) in 99 participants allocated to four recovery conditions (control N = 26, music N = 23, odor N = 24, music+odor N = 26). The stressing event triggered both a significant increase in EDA and decrease in HF‐HRV (compared to baseline). During the recovery period, the odor elicited a greater decrease in EDA compared to an odorless silent control, whereas no difference in HRV was observed. Conversely, during this period, music elicited a greater increase in HF‐HRV compared to control whereas no difference in EDA was observed. Strikingly, in the multimodal music+odor condition, no beneficial effect was observed on ANS indexes 30 min after stress. Overall, our study confirms that both olfactory and musical stimuli have relaxing effects after stress on ANS when presented separately only, which might rely on distinct neural mechanisms and autonomic pathways.

Relaxing and stimulating ambient odors influence preferences for musical tempo

“…Finally, the present study demonstrates that odors distort time perception in a situation in which participants are not aware of the presence of olfactory stimuli. This supports the idea that expectations triggered by conscious perception do not entirely account for the relaxing and stimulating effects of odors, and that prior associative-learning representations might also play a role, even though these representations are not accessed consciously (for a discussion see Baccarani et al, 2023; Baccarani, Grondin, et al, 2021). This would be especially true if one considers that olfactory neural afferences have privileged links with emotion- and memory-related brain structures such as the amygdala and hippocampus (Herz, 2016).…”

Effect of background music on STress Responses Amongst Undergraduates and Surgeons performing Simulated Surgical tasks: A randomised cross-over interventional trial (The STRAUSS Study)

“…45 Finally, relaxing music (slow-paced classical pieces) when compared to control showed greater return to baseline in high frequency HRV after a stressing event suggesting a role for music in the recovery for surgeons after stressful operations. 50 Transcranial Doppler ultrasound was rst used by Aaslid et al 51 to measure cerebral blood velocity in dynamic cerebral autoregulation research, and its application to surgeons is novel. Cerebral perfusion (i.e., MCA Vm) was signi cantly increased during task performance, with maximal increase during the midpoint of the operation, although a difference between music and control conditions was not observed.…”