Effects of Hinoki (Japanese cypress) essential oil olfactory stimulation on prefrontal cortex activity and autonomic nervous activity: a crossover trial

Effects of Hinoki (Japanese cypress) essential oil olfactory stimulation on prefrontal cortex activity and autonomic nervous activity: a crossover trial - Effects of Hinoki (Japanese cypress) essential oil olfactory stimulation on prefrontal cortex activity and autonomic nervous activity: a crossover trial

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000059634

Enrollment

Registered

2025-11-04

Start date

2025-11-04

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy person

Interventions

Olfactory stimulation with essential oil extracted from Japanese cypress (Hinoki) wood (90 s) -&gt

Rest period -&gt

Control: No odor (air, 90 s) Control: No odor (air, 90 s) -&gt

Olfactory stimulation with essential oil extracted from Japanese cypress (Hinoki) wood (90 s)

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Healthy person

Exclusion criteria

Exclusion criteria: 1) History of allergy to Hinoki (Japanese cypress) wood or Hinoki essential oil. 2) Respiratory conditions such as asthma, chronic rhinitis, or seasonal allergic rhinitis (hay fever), by self-report or prior physician diagnosis. 3) Currently receiving treatment for any disease at a medical institution. 4) Current smoking habit. 5) History or diagnosis of cardiac arrhythmia. 6) Menstruation on the test day (female participants only).

Design outcomes

Primary

Measure	Time frame
1) Prefrontal activity using near-infrared time-resolved spectroscopy 2) Sympathetic and parasympathetic nervous activity as indicated by heart rate variability 3) Heart rate	—

Secondary

Measure	Time frame
1) Profile of Mood State (POMS2 short form) 2) Modified semantic differential method 3) Kwansei Gakuin (KG) daily life questionnaire 4) Tokai University daily life survey 5) Type A tendency distinction table 6) Patient Health Qeustionnaire-9 4) Trait Anxiety of State-Trait Anxiety Inventory	—

Countries

Japan

Contacts

Public ContactHarumi Ikei

Chiba University Center for Environment, Health and Field Sciences

hikei@chiba-u.jp04-7137-8184

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026