title: Overshadowing and stimulus duration.
abstract: In 3 experiments, the authors investigated the effect of stimulus duration on overshadowing. Experiments 1 and 2 examined responding to a target conditioned stimulus (CS1) when it was conditioned in compound with a coterminating overshadowing stimulus (CS2) that was longer, shorter, or of the same duration (the long, short, and matched groups, respectively). Equal overshadowing of conditioning to CS1 was obtained in all 3 conditions relative to a control group conditioned to the light alone. There were, however, differences in responding to CS2 as a function of its absolute duration. Experiment 3 examined the contribution of the food-food interval/CS onset-food interval ratio to these findings. In Experiments 1 and 2, the ratio differed for the overshadowing CS but not for the target CS. In Experiment 3, this arrangement was reversed, but the pattern of results remained the same. The implications of these findings for trial-based and real-time models of conditioning are discussed.
authors.affiliation: Division of Psychology, School of Biology and Psychology, Newcastle University, UK. domhnall.jennings@ncl.ac.uk
authors.forename: Dómhnall J
authors.initials: DJ
authors.lastname: Jennings
authors.forename: Charlotte
authors.initials: C
authors.lastname: Bonardi
authors.forename: Kimberly
authors.initials: K
authors.lastname: Kirkpatrick
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001245:Association Learning; D001288:Attention; D003214:Conditioning, Classical; D003463:Cues; D008297:Male; D010775:Photic Stimulation; D051381:Rats; D011930:Reaction Time; D013998:Time Perception