Blocking of associative learning by explicit descriptions

“Blocking of associative learning by explicit descriptions”

People given written descriptions often learn and decide differently from those learning from experience, even in formally identical tasks.
This paper presents two experiments detailing how telling participants about the value of one stimulus impacts a keystone learning effect – blocking.
The paper investigates if descriptions can be used to effectively block future trial-by-trial learning. Participants were presented with coloured shape stimuli and asked if those shapes caused reward.
Experiment 1 found both standard, trial-by-trial experienced blocking and the novel effect of described blocking of future trial-by-trial learning.
Experiment 2 investigated the conditions that promote described blocking by manipulating the training that occurred prior to exposure to the description.
In the Pre-training Present group, participants exposed to a training set of compound and elemental stimuli produced more pronounced blocking than the Pre-training Absent group, which had no such training.
These results show that explicit descriptions about causal relations can block learning from subsequent experience, providing a new extension of associative learning toward the verbal domain.

These two experiments provide a pair of clear, incentivised, pre-registered, demonstrations of the power of description to block future experience in a mixed description-plus-experience environment.
In the real world, people continuously navigate a complex environment where prior experience meets what they are told by external sources—from encountering road signs whilst driving to reading the news about current events.
Our results, that descriptions can effectively block future learning, suggest associative learning methodologies may be insightful in understanding these complex, mixed-information environments.
Classic phenomena such as blocking could extend into many of the complex real-world environments in which directly learnt information interacts with written or verbal information.