Positive serial dependence effects in rating food images for appeal and calories

Poster Presentation 43.420: Monday, May 22, 2023, 8:30 am – 12:30 pm, Pavilion
Session: Visual Working Memory: Serial dependence

David Alais1 (), Thomas Carlson1; 1University of Sydney

Many studies have shown that recent perceptual history can bias present perception, known as serial dependence. We examined this phenomenon for sequences of food images that participants rated for either ‘appeal’ or ‘calories’ and found strong positive dependencies. A large sample in an online experiment (n>300) made 450 ratings of food images (150 stimuli, randomly presented three times), rating appeal and calories in separate counterbalanced blocks. A first analysis based on the previous trial’s rating showed that for both appeal and calories there were clear assimilations towards the preceding trial’s rating which were well described by a difference of Gaussian model. The amplitude of the serial effect for appeal was roughly twice that for calories. For food appeal, the serial effect was greater in males than females. There were no sex differences for calorie ratings. These serial analyses were based on previous response, which emphasises perceptual decision. A second analysis based on the previous stimulus (using the mean of all ratings of that image) was conducted. Only the serial effect for calories was significant on the stimulus analysis, possibly indicating a perceptual effect of caloric value of food. Various demographic data and scales were recorded before the experiment and two correlations survived multiple comparisons. For appeal ratings, males showed greater amplitude of serial effect with increasing tiredness. For calorie ratings, all subjects showed greater serial bandwidth with increasing BMI.