title: Assessment of olfactory detection thresholds in children with autism spectrum disorders using a pulse ejection system.
abstract: BACKGROUND
  Atypical responsiveness to olfactory stimuli has been reported as the strongest predictor of social impairment in children with autism spectrum disorders (ASD). However, previous laboratory-based sensory psychophysical studies that have aimed to investigate olfactory sensitivity in children with ASD have produced inconsistent results. The methodology of these studies is limited by several factors, and more sophisticated approaches are required to produce consistent results.
  
  
  METHODS
  We measured olfactory detection thresholds in children with ASD and typical development (TD) using a pulse ejection system-a newly developed methodology designed to resolve problems encountered in previous studies. The two odorants used as stimuli were isoamyl acetate and allyl caproate.
  
  
  RESULTS
  Forty-three participants took part in this study: 23 (6 females, 17 males) children with ASD and 20 with TD (6 females, 14 males). Olfactory detection thresholds of children with ASD were significantly higher than those of TD children with both isoamyl acetate (2.85 ± 0.28 vs 1.57 ± 0.15; p < 0.001) and allyl caproate ( 3.30 ± 0.23 vs 1.17 ± 0.08; p < 0.001).
  
  
  CONCLUSIONS
  We found impaired olfactory detection thresholds in children with ASD. Our results contribute to a better understanding of the olfactory abnormalities that children with ASD experience. Considering the role and effect that odors play in our daily lives, insensitivity to some odorants might have a tremendous impact on children with ASD. Future studies of olfactory processing in ASD may reveal important links between brain function, clinically relevant behavior, and treatment.
authors.affiliation: Research Center for Child Mental Development, University of Fukui, 23-3, Matsuokashimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193 Japan ; Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kumazaki
authors.affiliation: Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Muramatsu
authors.affiliation: Research Center for Child Mental Development, University of Fukui, 23-3, Matsuokashimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193 Japan.
authors.forename: Takashi X
authors.initials: TX
authors.lastname: Fujisawa
authors.affiliation: Donguri Psycho Developmental Clinic, Setagayaterasu # 1F, 4-14-5 Minamikarasuyama, Setagaya-ku, Tokyo 157-0062 Japan.
authors.forename: Masutomo
authors.initials: M
authors.lastname: Miyao
authors.affiliation: Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522 Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Matsuura
authors.affiliation: Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522 Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Okada
authors.affiliation: Research Center for Child Mental Development, University of Fukui, 23-3, Matsuokashimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193 Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Kosaka
authors.affiliation: Research Center for Child Mental Development, University of Fukui, 23-3, Matsuokashimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193 Japan.
authors.forename: Akemi
authors.initials: A
authors.lastname: Tomoda
authors.affiliation: Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Mimura
mesh_terms: D000293:Adolescent; D000336:Aerosols; D000067877:Autism Spectrum Disorder / Q000503:physiopathology* / Q000523:psychology; D002208:Caproates; D016022:Case-Control Studies; D002648:Child; D019719:Diagnostic Equipment; D004867:Equipment Design; D005260:Female; D006801:Humans; D006987:Hypesthesia / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology; D008297:Male; D009812:Odorants; D055696:Olfactory Perception / Q000502:physiology*; D000439:Pentanols; D011673:Pulsatile Flow; D012684:Sensory Thresholds / Q000502:physiology*
chemical_list: D000336:Aerosols; D002208:Caproates; D000439:Pentanols; C016972:allyl caproate; C020377:isoamyl acetate
keywords: Autism spectrum disorder; Laboratory-based studies; Olfaction; Olfactory detection threshold; Pulse ejection system