No support for dual process accounts of human affective learning in simple Pavlovian conditioning

Abstract

Dual process accounts of affective learning state that the learning of likes and dislikes reflects a learning mechanism that is distinct from the one reflected in expectancy learning, the learning of signal relationships, and has different empirical characteristics. Affective learning, for example, is said not to be affected by: (a) extinction training; (b) occasion setting; (c) cue competition; and (d) awareness of the CS‐US contingencies. These predictions were tested in a series of experiments that employed simple Pavlovian conditioning procedures. Neutral visual pictures of geometric shapes, or tactile conditional stimuli (CS) were paired with aversive electrotactile unconditional stimuli (US). Dependent measures were physiological (skin conductance, blink startle modulation) or verbal (US expectancy, on‐line and off‐line ratings of CS pleasantness). Different combinations of these dependent measures were employed across different experiments in an attempt to assess affective and expectancy learning simultaneously. Changes in CS pleasantness as indexed by ratings or blink startle modulation were readily observed. However, contrary to the predictions from dual‐process accounts, results indicated that acquired CS unpleasantness is subject to extinction, occasion setting, cue competition, and not found in absence of CS‐US contingency awareness.

Notes

Throughout the manuscript we use the term “affective learning” as a descriptive term to address the empirical phenomenon that the valence of a CS can change if it is paired with an emotionally salient US. The term “evaluative learning” was avoided as it is often used synonymously with a dual process account of affective learning.

Correspondence should be addressed to Dr Ottmar V. Lipp, School of Psychology, The University of Queensland, QLD, 4072, Australia; e‐mail: [email protected]

Grants A10027218, A79600404, and 00/ARCS051 from the Australian Research Council supported this work. The present paper was conceptualised during two Special Interest Meetings on the Acquisition of Affect sponsored by the Fund for Scientific Research–Flanders (Belgium), LeLignely, Belgium, May 2001 and 2002.