Expectancy of stress-reducing aromatherapy effect and performance on a stress-sensitive cognitive task

Area of Science:

• Neuroscience
• Psychology
• Cognitive Science

Background:

• Stress negatively impacts cognitive function.
• Aromatherapy is a popular stress-reduction technique, but its efficacy and mechanisms remain unclear.
• The role of expectancy in therapeutic interventions requires further investigation.

Purpose of the Study:

• To investigate the stress-reducing effects of aromatherapy on cognitive function.
• To examine the impact of aromatherapy on go/no-go (GNG) task performance and event-related potentials (ERPs).
• To assess the influence of expectancy on aromatherapy's effectiveness.

Main Methods:

• 81 adults were randomized into three aroma groups (active, detectable placebo, undetectable placebo) and two priming subgroups (suggesting stress-reducing effects or no priming).
• Cognitive performance (GNG task), ERPs, subjective expectations, and stress ratings were measured before and after a stressor.
• Statistical analyses examined aroma and priming effects on cognitive and physiological measures.

Main Results:

• No significant aroma-specific effects on stress levels or cognitive performance were observed.
• Participants receiving a prime exhibited faster post-stress reaction times compared to the no-prime group, irrespective of the aroma experienced.
• A significant interaction in N200 amplitude indicated distinct ERP patterns between baseline and post-stress conditions based on priming, suggesting improved response inhibition and attention.

Conclusions:

• Aromatherapy did not demonstrate specific stress-reducing or cognitive-enhancing effects in this study.
• Expectancy, induced by priming, played a significant role in modulating post-stress cognitive performance, particularly in response inhibition and attention.
• These findings underscore the importance of psychological factors, such as expectancy, in the context of stress management interventions.