title: A freezing-like posture to pictures of mutilation.
abstract: Postural sway and heart rate were recorded in young men viewing emotionally engaging pictures. It was hypothesized that they would show a human analog of "freezing" behavior (i.e., immobility and heart rate deceleration) when confronted with a sustained block of unpleasant (mutilation) images, relative to their response to pleasant/arousing (sport action) or neutral (objects) pictures. Volunteers stood on a stabilometric platform during picture viewing. Significantly reduced body sway was recorded during the unpleasant pictures, along with increased mean power frequency (indexing muscle stiffness). Heart rate during unpleasant pictures also showed the expected greater deceleration. This pattern resembles the "freezing" and "fear bradycardia" seen in many species when confronted with threatening stimuli, mediated by neural circuits that promote defensive survival.
authors.affiliation: Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Tatiana M
authors.initials: TM
authors.lastname: Azevedo
authors.forename: Eliane
authors.initials: E
authors.lastname: Volchan
authors.forename: Luiz A
authors.initials: LA
authors.lastname: Imbiriba
authors.forename: Erika C
authors.initials: EC
authors.lastname: Rodrigues
authors.forename: José M
authors.initials: JM
authors.lastname: Oliveira
authors.forename: Liliam F
authors.initials: LF
authors.lastname: Oliveira
authors.forename: Luiz G
authors.initials: LG
authors.lastname: Lutterbach
authors.forename: Claudia D
authors.initials: CD
authors.lastname: Vargas
mesh_terms: D000328:Adult; D001919:Bradycardia / Q000523:psychology; D004644:Emotions / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D011187:Posture / Q000502:physiology*