Sensory expectations based on product-extrinsic food cues: An interdisciplinary review of the empirical evidence and theoretical accounts

• We summarize the various theories of expectations.
• We review the applied research about expectancy effects on people’s sensory perception of foods.
• We focus on the effect of food-extrinsic cues, namely labels and pictorial cues.
• The relevant evidence from cognitive neuroscience is also reviewed.
• We provide an additional perspective, in terms of predictive coding and Bayesian theories.

This article constitutes a state-of-the-art review of the literature on the effects of expectations on the sensory perception of food and drink by humans. In the ‘Introduction’, we summarize the theoretical models of expectations that have been put forward. In the ‘Empirical research utilizing direct methods’ section, we describe the influence that expectations created by a variety of product extrinsic cues have on sensory perception, hedonic appraisal, and intake/consumption. We critically evaluate the evidence that has emerged from both laboratory studies and real-world research conducted in the setting of the restaurant, canteen, and bar. This literature review is focused primarily on those studies that have demonstrated an effect on tasting. Crucially, this review goes beyond previous work in the area by highlighting the relevant cognitive neuroscience literature (see the section ‘Applied research through the lens of cognitive neuroscience methods’) and the postulated psychological mechanisms of expectation in terms of recent accounts of predictive coding and Bayesian decision theory (see the ‘Predictive coding and expectations’ section).