Pleasant Odors for Craving

(OdorCrave Trial)

Overseen By Michael A Sayette, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Pittsburgh

Must not be taking: Psychoactive drugs

Disqualifiers: Neurological, Psychotic disorders, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 4

250 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how pleasant smells affect cigarette cravings. Researchers will compare the effects of a pleasant odor to a neutral one (referred to as "Odor Blank") on people who smoke cigarettes, to determine if pleasant smells can reduce the urge to smoke. Participants must undergo certain tests and use a smartphone app to report cravings over a week. The study seeks adult smokers who either smoke daily or occasionally but not more than 20 cigarettes a day, and who have a good sense of smell. As an unphased trial, this study offers a unique opportunity to contribute to innovative research on smoking cessation.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it does exclude those with current psychoactive drug use and drug dependence outside of nicotine or caffeine.

What prior data suggests that these olfactory cues are safe for use in this study?

Studies have shown that pleasant smells can significantly reduce the urge to smoke. For example, when people smelled something nice, their craving scores dropped by an average of 19.3 points. In comparison, when they smelled something neutral, like a blank odor, the scores fell by only 11.2 points. Although specific safety data on using pleasant smells to reduce cravings is limited, this method is considered safe because it involves only smelling scents that participants like. These studies have reported no negative effects from using pleasant smells. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using pleasant odors to help manage cigarette cravings because this approach taps into the power of our sense of smell to influence behavior. Unlike traditional methods like nicotine replacement therapies or medications, which focus on reducing nicotine dependence, this technique uses olfactory cues to disrupt craving cycles directly. By using a pleasant scent that participants find both enjoyable and intense, this method aims to provide immediate distraction and relief from cravings without reliance on chemicals or drugs. This approach offers a novel, non-invasive way to support individuals in their journey to quit smoking.

What evidence suggests that pleasant odors might be an effective treatment for cigarette craving?

This trial will compare the effects of pleasant odors with a neutral odor (odor blank) on cigarette cravings. Research has shown that pleasant smells can help reduce the urge to smoke. In one study, both pleasant and unpleasant smells lowered the desire to smoke more than a neutral smell did. Another study found that intentionally smelling a pleasant scent could temporarily lessen the craving to smoke. These findings suggest that pleasant smells might aid those trying to quit smoking by managing their cravings. Overall, the potential of pleasant odors in effectively reducing cigarette cravings is highlighted. ^{1 2 4 6 7}

Who Is on the Research Team?

Michael A Sayette, PhD

Principal Investigator

The University of Pittsburgh

Marc N Coutanche, PhD

Principal Investigator

The University of Pittsburgh

Are You a Good Fit for This Trial?

This trial is for right-handed, English-speaking adults aged 18-49 who smoke cigarettes daily (10-30 per day) or nondaily. They must weigh less than 250lbs to fit in an MRI machine safely, have a working smartphone, and an intact sense of smell. Smokers with extreme habits or other drug dependencies besides nicotine or caffeine are excluded.

Inclusion Criteria

Fluent in English

No drug dependence outside of nicotine or caffeine

I weigh 250lbs or less and can safely undergo an MRI.

Exclusion Criteria

Individuals will also be excluded if they report any allergies to the odors used in our study

Baseline CO readings will need to be consistent with our criteria for daily and nondaily smokers for participants to be considered eligible. Specifically, we plan to rule out extremely heavy smokers (nondeprived CO > 55, for whom the smoking abstinence requirement may be too extreme to allow a sensitive test of our OC manipulation) and daily smokers with a nondeprived CO reading <10 PPM as this would raise concerns that they do smoke enough to be classified as a daily smoker.

I have a current neurological or psychotic disorder.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 week

1 visit (in-person)

Baseline Assessment

Participants complete a baseline breath carbon monoxide reading, odor threshold test, and self-report measures

1 hour

1 visit (in-person)

fMRI Session

Participants undergo a 60-minute fMRI scan including structural, resting state, and task-based data collection

1 week after screening

1 visit (in-person)

Behavioral Session

Participants complete behavioral tasks to assess the impact of olfactory cues on cigarette craving

1 week after fMRI session

1 visit (in-person)

Ecological Momentary Assessment (EMA)

Participants monitor cigarette cravings over a 7-day period to evaluate the impact of olfactory cues on naturally occurring craving

7 days

Follow-up

Participants are monitored for safety and effectiveness after the main study procedures

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Odor Blank
• Pleasant Odor

Trial Overview The study tests if pleasant smells can reduce cigarette cravings more effectively than neutral odors. It involves three visits: baseline assessments, fMRI scans while exposed to smoking cues and either pleasant/neutral smells, and behavioral tests on craving responses. Participants will also track their cravings for a week using their smartphones.

How Is the Trial Designed?

Group I: Pleasant Odor Experimental Treatment 1 Intervention

Participants in this condition will sniff the olfactory cue they rate as both pleasant (\>5 on the 1-9 scale) and the most intense following cigarette cue exposure. If this odor is the same as their self-reported preferred e-cigarette flavor, we will choose the next most intense odor out of the odors rated as pleasant.

Group II: Odor Blank Experimental Treatment 1 Intervention

Participants in this condition will sniff a neutral olfactory cue (odor blank) following cigarette cue exposure.

Who Is Running the Clinical Trial?

University of Pittsburgh

Lead Sponsor

Trials

1,820

Recruited

16,360,000+

National Center for Complementary and Integrative Health (NCCIH)

Collaborator

Trials

886

Recruited

677,000+

Published Research Related to This Trial

The study involving 19 healthy participants found that a congruent visual context enhances the perception of pleasant odors, specifically increasing the perceived flowery note of a floral scent, which could have implications for olfactory therapy in patients with smell disorders.

In contrast, unpleasant odors were not influenced by visual context, and incongruent visual cues disrupted odor sampling behavior, suggesting a protective mechanism against unexpected aversive stimuli.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Visual Priming Influences Olfactomotor Response and Perceptual Experience of Smells. Manesse, C., Fournel, A., Bensafi, M., et al.[2021]

In a study involving 232 abstinent smokers, pleasant olfactory cues (OCs) were found to significantly reduce cigarette cravings compared to neutral or tobacco-related odors, with the effect lasting for at least 5 minutes.

Participants with stronger autobiographical memory systems responded better to the craving-reducing effects of pleasant OCs, suggesting that these cues could be a promising tool for smoking cessation strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pleasant olfactory cues can reduce cigarette craving. Sayette, MA., Marchetti, MA., Herz, RS., et al.[2021]

A field study near six odor-emitting plants revealed that the pleasantness of odors significantly affects community annoyance, with pleasant odors causing little to no annoyance, while neutral and unpleasant odors do lead to higher levels of annoyance.

The study established that the frequency of reported health symptoms was directly linked to odor annoyance, leading to modifications in existing guidelines for managing odor exposure in communities.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Odor frequency and odor annoyance Part II: dose-response associations and their modification by hedonic tone. Sucker, K., Both, R., Bischoff, M., et al.[2021]

In a study involving 21 women, exposure to palatable food odors for 20 minutes significantly increased both general appetite and sensory-specific appetite (SSA) without becoming satiating over time.

Food odors enhanced the desire for congruent foods (e.g., savory odors increased appetite for savory foods) while decreasing the appetite for incongruent foods, suggesting that the body prepares for specific types of food based on the odors present.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Odors: appetizing or satiating? Development of appetite during odor exposure over time. Ramaekers, MG., Boesveldt, S., Lakemond, CM., et al.[2021]

About 35% of neurons in the orbitofrontal cortex are involved in associating odors with tastes, indicating that our brain learns to connect what we smell with what we taste over time.

Neurons in this area also show decreased responses to foods we've eaten to satiety, which helps explain why we may lose interest in certain foods after eating them, while still responding to the smells of other foods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The rules of formation of the olfactory representations found in the orbitofrontal cortex olfactory areas in primates. Rolls, ET.[2019]

A study comparing acetone-exposed workers and naive controls revealed significant differences in how they perceived irritation from acetone, highlighting the influence of exposure history on irritancy judgments.

The perceived intensity of acetone's odor and individual response bias were key factors affecting reported irritancy, suggesting that both factors should be considered in evaluating chemical irritancy in workplace and experimental settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Perceived odor, irritation, and health symptoms following short-term exposure to acetone. Dalton, P., Wysocki, CJ., Brody, MJ., et al.[2019]

Exposure to both pleasant and unpleasant odors significantly reduced the urge to smoke in nicotine-deprived smokers compared to a control odor (water), suggesting that olfactory stimuli can be a useful tool for craving reduction.

Odors that did not elicit negative facial expressions were more effective in reducing the urge to smoke, indicating that the emotional response to the odor may play a role in its effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of olfactory stimuli on urge reduction in smokers. Sayette, MA., Parrott, DJ.[2019]

A brief exposure to a neutral unfamiliar odor can significantly reduce cravings for highly desired foods, as shown in a study comparing olfactory tasks to auditory tasks and control conditions.

Specifically, the study found that smelling an odor reduced cravings for chocolate, suggesting that olfactory stimulation could be a useful strategy for managing unwanted food cravings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Olfactory stimulation curbs food cravings. Kemps, E., Tiggemann, M.[2020]

In a study with 24 healthy female participants, it was found that being satiated (full) significantly lowered the detection threshold for the food-related odor isoamyl acetate, meaning they could smell it better when full compared to when hungry.

While satiety decreased the pleasantness of the food odor, it did not affect the detection threshold for a non-food odor (n-butanol), suggesting that the state of satiety influences how we perceive food-related smells, which may play a role in controlling food intake.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Olfactory detection thresholds and pleasantness of a food-related and a non-food odour in hunger and satiety. Albrecht, J., Schreder, T., Kleemann, AM., et al.[2013]

In a study with 90 participants aged 18 to 35, exposure to pleasant scents like baby powder and chocolate led to longer viewing times of images, improved mood, and reduced hunger ratings compared to no scent.

Specific odors influenced different outcomes: chocolate scent heightened arousal, while baby powder scent was associated with fewer reported health symptoms, indicating that pleasant odors can have both general and specific effects on mood and perception.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pleasant odors and congruency: effects on approach behavior. Knasko, SC.[2019]

In a study with 29 healthy-weight females, smelling food odours that matched the taste (sweet or savoury) significantly increased appetite for similar-tasting foods compared to different-tasting or neutral foods.

The effect of food odours also extended to energy density, where odours signaling high or low energy density increased appetite for congruent food products, regardless of the participants' hunger state.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Food Odours Direct Specific Appetite. Zoon, HF., de Graaf, C., Boesveldt, S.[2022]

The study found that the perception of food odors changes based on whether a person is hungry or satiated, with both fatty and non-fat food odors being rated as less pleasant and appetent when subjects were full.

The decrease in desire (appetence) for fatty food odors was more pronounced than for non-fat food odors, indicating that alliesthesia is more sensitive to the type of food odor, and that measuring appetence is a better way to understand how internal states affect reward perception.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Alliesthesia is greater for odors of fatty foods than of non-fat foods. Plailly, J., Luangraj, N., Nicklaus, S., et al.[2016]

Olfactory priming can reactivate a preference for chocolate in sated mice, suggesting that smells can trigger cravings even after a period of abstinence from palatable foods.

This study highlights the importance of olfactory cues in the relapse of maladaptive eating habits, indicating that addressing smell-related triggers could be crucial in treating eating disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Olfactory priming reinstates extinguished chocolate-induced conditioned place preference. La Mela, I., Latagliata, EC., Patrono, E., et al.[2019]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6529945/

Pleasant Olfactory Cues Can Reduce Cigarette Craving - PMC Results indicated that exposure to pleasant or unpleasant OCs (similarly) reduced urge to smoke relative to exposure to the control OC. The drop in urge among ...

2. apa.org apa.org/news/press/releases/2019/04/decrease-cigarette-craving

Sniffing pleasant odors may decrease cigarette craving Deliberately inhaling a pleasant aroma may be enough to reduce the urge to light up, at least temporarily, and could be used as part of an effective smoking ...

3. clinicaltrials.gov clinicaltrials.gov/study/NCT04902469

Study Details | NCT04902469 | Cognitive and Affective ... The investigators aim to conduct a comprehensive analysis of craving and to test the impact of pleasant olfactory cues (OCs) on craving relief. Towards these ...

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3712336/

Effects of Olfactory Stimuli on Urge Reduction in Smokers - PMC The major finding was that sniffing hedonically evaluative (pleasant and unpleasant) odors reduced reported urge to smoke.

5. neurosciencenews.com neurosciencenews.com/olfaction-cigarette-craving-11085/

Sniffing pleasant odors may decrease cigarette craving Our research suggests that the use of pleasant odors shows promise for controlling nicotine cravings in individuals who are trying to quit smoking.

6. withpower.com withpower.com/trial/phase-8-2021-82331

Pleasant Odors for Craving (OdorCrave Trial) The research does not provide specific safety data on using pleasant odors for reducing cravings ... olfactory stimuli can be a useful tool for craving reduction.

7. reuters.com reuters.com/article/business/healthcare-pharmaceuticals/pleasant-smells-may-curb-cigarette-cravings-idUSKCN1RT24J/

Pleasant smells may curb cigarette cravings With a pleasant odor, craving scores dropped by an average 19.3 points, with a tobacco odor they dropped 11.7 points and with the blank, by 11.2 ...