Abstract
The current research aimed to further current knowledge on the psychological processes that underpin human outcome-selective Pavlovian-instrumental transfer (PIT) effects. PIT reflects the capacity of a Pavlovian stimulus to selectively potentiate an instrumental response that predicts a common rewarding outcome. PIT effects are often suggested to reflect a relatively automatic S-O-R mechanism, where the stimulus activates the sensory properties of the outcome, which then automatically triggers associated instrumental responses. The current research tested this S-O-R account of PIT against a propositional expected utility theory, which suggests that PIT effects reflect verbalizable inferences about the probability and value of each outcome. Chapter 1 reviews the relevant literature. Chapters 2-4 then report 11 experiments that aimed to set the S-O-R and propositional theories against one another. In Chapter 2, two experiments demonstrated that PIT is sensitive to a reversal instruction (Experiment 2), but is robust against a time pressure (Experiment 1) and concurrent load (Experiment 2) manipulation. Chapter 3 details the development of a novel outcome devaluation procedure, and reports four experiments that examined the effect of both outcome devaluation and verbal instructions on PIT. These experiments demonstrated that a typical PIT procedure produces PIT effects that are insensitive to a very strong devaluation manipulation. Furthermore, PIT effects were observed for a devalued outcome even when an S-O-R mechanism was unlikely to control behaviour. Chapter 4 reports five experiments that show that PIT is highly sensitive to outcome devaluation when multiple outcomes and responses are cued on every transfer test trial. Chapter 5 therefore concludes that, on balance, the results provide converging support for the propositional expected utility theory of PIT.
Document Type
Thesis
Publication Date
2017
Recommended Citation
Seabrooke, T. (2017) Controlled and automatic processes in Pavlovian-instrumental transfer. Thesis. University of Plymouth. Retrieved from https://pearl.plymouth.ac.uk/foh-theses-other/94