Contradictory Behavioral Biases Result from the Influence of Past Stimuli on Perception
Figure 5
A schematic explanation of the Interval Bias as resulting from the effect of history.
Using the same notation of Fig. 1. The horizontal dashed line represents M, the memory trace which estimates the value of the mean stimulus in the block. The value of this trace is not the global mean and is expected to vary between trials. The vertical arrow presents the contraction of the first stimulus towards the memory trace. The arrow is red when this contraction impairs performance, since it increases the probability of an incorrect response. The arrow is white when this contraction is beneficial to performance. A–D: exemplar trials from the Reference protocol; A: a Ref1, trial; B: a Ref1,
trial; C: a Ref2,
trial; D: a Ref2,
trial; E–H: exemplar trials from the Reference-Lower protocol; E: an easy Ref1 trial; F: a difficult Ref1 trial; G: an easy Ref2 trial; H: a difficult Ref2 trial. Overall, in the Reference-Lower protocol performance is expected to be higher in Ref2 trials, and in the Reference protocol performance is expected to be higher in Ref1 trials.