title: Effects of CS-US interval modification on diminution of the unconditioned response in electrodermal classical conditioning.
abstract: The purpose of this experiment was to study whether interstimulus interval (ISI) modification differentially affects the amplitude of the unconditioned response (UR amp.). Seventy-five volunteer subjects received discrimination training with an interval between conditioned stimulus (CS) and unconditioned stimulus (US; aversive white noise) of 8 s. After the discrimination training phase, subjects exhibiting discriminative control were randomized into three groups that differed according to the ISI, of 1, 5 or 8 s. The subjects of each group were then tested with five presentations of CS + /US. The results demonstrate that the UR showed a greater amplitude when an ISI of 8 s was used than with ISIs of 1 or 5 s. No significant differences were found between the UR amp. of the 1- and 5-s ISI groups. These findings are discussed as a result of a hypothetical experimentally induced blend of the anticipatory CRs with the UR.
authors.affiliation: Departamento de Psicología, Universidad de La Coruña, Spain. jlmarc@udc.es
authors.forename: J L
authors.initials: JL
authors.lastname: Marcos
authors.forename: J
authors.initials: J
authors.lastname: Redondo
mesh_terms: D000328:Adult; D001767:Blinking / Q000502:physiology; D003214:Conditioning, Classical / Q000502:physiology*; D005260:Female; D005712:Galvanic Skin Response; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D011897:Random Allocation; D013997:Time Factors