title: No bridge too high: infants decide whether to cross based on the probability of falling not the severity of the potential fall.
abstract: Do infants, like adults, consider both the probability of falling and the severity of a potential fall when deciding whether to cross a bridge? Crawling and walking infants were encouraged to cross bridges varying in width over a small drop-off, a large drop-off, or no drop-off. Bridge width affects the probability of falling, whereas drop-off height affects the severity of the potential fall. For both crawlers and walkers, decisions about crossing bridges depended only on the probability of falling: As bridge width decreased, attempts to cross decreased, and gait modifications and exploration increased, but behaviors did not differ between small and large drop-off conditions. Similarly, decisions about descent depended on the probability of falling: Infants backed or crawled into the small drop-off, but avoided the large drop-off. With no drop-off, infants ran straight across. Results indicate that experienced crawlers and walkers accurately perceive affordances for locomotion, but they do not yet consider the severity of a potential fall when making decisions for action.
authors.affiliation: Department of Psychology, New York University, USA.
authors.forename: Kari S
authors.initials: KS
authors.lastname: Kretch
authors.forename: Karen E
authors.initials: KE
authors.lastname: Adolph
mesh_terms: D001288:Attention; D003657:Decision Making; D005260:Female; D006801:Humans; D007223:Infant; D018730:Infant Behavior; D008124:Locomotion; D008297:Male; D012309:Risk-Taking; D013028:Space Perception