Jan de Houwer
Professor, Ghent University

Conditioning as a higher-order cognitive phenomenon: Implications for placebo research

Contrary to the available evidence, conditioning is often conceptualized as “as a kind of low-level mechanical process in which control over a response is passed from one stimulus to another” (Rescorla, 1988, p. 152). More modern views on conditioning, however, do attribute a crucial role to cognitive processes. Most learning researchers endorse the idea that cognitive processes moderate the formation of associations between stimulus representations. More recently, it has been argued that conditioning is mediated by the non-automatic formation of propositional beliefs about the relation between stimuli. Conditioning in verbal humans has even been described as a symbolic phenomenon in which stimulus pairings function as a symbolic cue for the way in which the stimuli are related. These modern views on conditioning imply that the relevance of conditioning for placebo research is not restricted to providing a non-cognitive mechanism for the emergence of placebo effects. Instead, stimulus pairings can function in ways similar to instructions, not only in shaping expectancies about the effects of drugs but also in allowing people to build models of the way in which drugs have their effects.


Jan De Houwer is a Professor at Ghent University (Belgium) where he heads the Learning and Implicit Processes Laboratory. His research is related to the manner in which spontaneous (automatic) preferences are learned and can be measured. Regarding the learning of preferences, he focuses on the role of stimulus pairings (associative learning). With regard to the measurement of preferences, he developed new reaction time measures and examined the processes underlying various measures. Jan De Houwer (co-)authored more than 250 publications in international journals including “Psychological Bulletin” and “Behavioral and Brain Sciences”. He was co-editor of the journal “Cognition and Emotion” and is a member of the editorial board of several journals including “Journal of Experimental Psychology: General”, “Psychological Bulletin”, and “Personality and Social Psychology Review”.