title: The development of sensitivity to biological motion in noise.
abstract: We investigated developmental changes in sensitivity to biological motion by asking 6-year-olds, 9-year-olds, and adults (twenty-four in each group) to discriminate point-light biological motion displays depicting one of a variety of human movements from scrambled versions of the same displays. When tested without noise dots, participants at all ages performed near ceiling levels and no differences in accuracy were found among the three age groups. Age differences emerged in the second task, in which we used a staircase procedure to determine threshold values of the number of noise dots that could be tolerated in producing a percentage correct value corresponding to a d' value of 1.4. Sensitivity to biological motion improved linearly with age (p < 0.01), with 6-year-olds performing significantly more poorly than adults. This immature performance contrasts with adult-like accuracy by 4 years of age for sensitivity to global motion (Parrish et al, 2005 Vision Research 45 827-837). The comparison implies an immaturity at 6 years of age in the neural networks involved specifically in the processing of biological motion, networks that may include the superior temporal sulcus (STS).
authors.affiliation: Department of Psychology, Neuroscience & Behaviour, McMaster University, 1280 Main St West, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Alejo
authors.initials: A
authors.lastname: Freire
authors.forename: Terri L
authors.initials: TL
authors.lastname: Lewis
authors.forename: Daphne
authors.initials: D
authors.lastname: Maurer
authors.forename: Randolph
authors.initials: R
authors.lastname: Blake
mesh_terms: D000328:Adult; D000367:Age Factors; D000375:Aging / Q000502:physiology*; D002648:Child; D002657:Child Development; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D009039:Motion Perception; D010775:Photic Stimulation / Q000379:methods; D011581:Psychological Tests; D012684:Sensory Thresholds