title: Shedding light on photosensitive behaviour in brown planaria (Dugesia Tigrina).
abstract: The planarian flatworm is one of the simplest animals to develop two eyecups that enable them to detect the presence and direction of light, which they typically avoid. In this study we assessed responses of planaria to different intensities of light. We found that they exhibited a graded, sigmoidal, photonegative response to light intensity. A two-octave increase in luminance (on the upward slope of the sigmoid) corresponded to a 9% increase in the speed planaria travelled to avoid light.
authors.affiliation: Division of Biomedical Sciences, St Georges, University of London, Cranmer Terrace, London SW17 0RE, UK.
authors.forename: Colin
authors.initials: C
authors.lastname: Davidson
authors.forename: Jose
authors.initials: J
authors.lastname: Prados
authors.forename: Claire L
authors.initials: CL
authors.lastname: Gibson
authors.forename: Andrew M J
authors.initials: AM
authors.lastname: Young
authors.forename: Darrel
authors.initials: D
authors.lastname: Barnes
authors.forename: Rachel
authors.initials: R
authors.lastname: Sherlock
authors.forename: Claire V
authors.initials: CV
authors.lastname: Hutchinson
mesh_terms: D000818:Animals; D001362:Avoidance Learning; D008027:Light; D009949:Orientation; D010932:Planarians; D011930:Reaction Time