We are looking for twenty women between 18 and 40 years of age to participate in a research study on perception of human pheromones in the brain. Participants should not have metal or electronic implants or devices within their body, should not have chronic upper respiratory illness or allergy to perfumes, and should not be on contraceptives. Participants will experience various odors during a functional magnetic resonance imaging (fMRI) scan, lasting approximately 20 minutes. Research participation is completely confidential. Participants will receive a voucher for a free combo meal at Cowamongus! (located in Animal & Food Sciences) as compensation for their participation. For more information about participation, or to enroll in the participant pool, please contact Dr. John McGlone at firstname.lastname@example.org or by phone at 806-834-8275, or Glenna Pirner at email@example.com. Interested participants will be emailed a questionnaire. If more than twenty participants enroll, the twenty that best match our criteria will be selected, and you will be notified of the decision via email. This study has been approved by the Human Research Protection Program at Texas Tech University.