Full Title: Positron tomographic emission study of olfactory induced emotional recall in veterans with and without combat-related posttraumatic stress disorder.

OBJECTIVE: Memory for odors is often associated with highly emotional experiences, and odors have long been noted by clinicians to be precipitants of trauma symptoms in posttraumatic stress disorder (PTSD). Primitive brain systems involved in fear responsivity and survival also mediate smell, including the olfactory cortex and amygdala. The purpose of this study was to measure neural correlates of olfaction in PTSD. METHODS: We exposed male combat veterans with PTSD (N = 8) and without PTSD (N = 8) to a set of smells, including diesel (related to traumatic memories of combat), and three other types of smells: odorless air, vanilla/coconut, and hydrogen sulfide (H2S) (respectively, a neutral, positive, and negative hedonic nontraumatic smell) in conjunction with PET imaging of cerebral blood flow and assessment of psychophysiological and behavioral symptoms. All subjects also underwent a baseline of olfactory acuity. RESULTS: PTSD patients rated diesel as unpleasant and distressing, resulting in increased PTSD symptoms and anxiety in PTSD versus combat controls. Exposure to diesel resulted in an increase in regional blood flow (rCBF) in amygdala, insula, medial prefrontal cortex, and anterior cingulate cortex, and decreased rCBF in lateral prefrontal cortex in PTSD in comparison to combat controls. Combat controls showed less rCBF changes on any smell, and did not show amygdala activation upon diesel exposure. CONCLUSIONS: These data support the hypothesis that in PTSD trauma-related smells can serve as strong emotional reminders. The findings indicate the involvement of a neural circuitry that shares olfactory elements and memory processing regions when exposed to trauma-related stimuli.

Psychopharmacol Bull. 2007;40(1):8-30.Related Articles, Links Vermetten E, Schmahl C, Southwick SM, Bremner JD. University Medical Center, Utrecht, The Netherlands. e.vermetten@umcutrecht.nl

BACKGROUND: Pediatric oncology patients commonly use complementary and alternative medicine (CAM), yet approximately only 50% of these patients discuss CAM with their oncologist. OBJECTIVE: The aim of this study is to assess barriers to CAM communication in pediatric oncology. DESIGN/METHODS: A 33-question survey was sent via electronic mail to 358 pediatric oncologists in the United States. RESULTS: Ninety pediatric oncologists completed the survey. Ninety-nine percent of pediatric oncologists think it is important to know what CAM therapies their patients use. However, less than half of pediatric oncologists routinely ask their patients about CAM. This is primarily because of a lack of time and knowledge. Many physicians think some forms of CAM may improve quality of life, such as massage (74%) and yoga (57%). Over half of physicians thought that dietary supplements, herbal medicine, special diets, vitamins, and chiropractic might be harmful to patients. CONCLUSIONS: Pediatric oncologists believe it is important to know which CAM therapies their patients use; however, they are not asking about them owing to lack of time and knowledge. To improve communication about CAM, increased physician education is needed. In addition, physicians should identify patients using potentially harmful CAM therapies. Furthermore, CAM research in pediatric oncology should focus on those modalities physicians believe may improve patient quality of life.

J Pediatr Hematol Oncol. 2009 Mar;31(3):177-82. Roth M, Lin J, Kim M, Moody K. Department of Pediatrics, Children's Hospital at Montefiore, Bronx, NY 10467, USA. mroth@montefiore.org