A systematic breakdown of stimulus-response associations

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Stimulus-response (S-R) learning comprises at least two different associations. A stimulus is associated to the action made in response to it (e.g., left finger press) and to the task in which the S-R event takes place (usually the classification of a stimulus as belonging to a category). Our previous work demonstrated that stimulus-classification (S-C) and stimulus-action (S-A) associations have independent effects on behaviour, that repetition learning strengthens both S-C and S-A associations, but S-C associations have more durable effects across time. However, such associations are interdependently processed (S-C-A learning), when participants receive rewards that exceed their expectations. We have also shown that S-R associations are formed not only when learning occurs through implementation but also through mere instruction. In this project we aim to break down the processes that underlie learning of both instructed and implemented S-R associations. In part A, we aim to elaborate whether mere instructions also result in the creation of independent S-C and S-A associations and whether these associations resemble those created via implementation regarding durability and stability. In part B, we propose an investigation of top-down influences on S-R learning components. Part B1 investigates whether retrieval of instructed and implemented S-R associations depends on the context in which they are learnt and on the context in which they are retrieved. Part B2 aims at assessing the impact of reward when implementing or instructing S-R associations. There we break down the impact of each parameter known to lead to the build-up of reward expectation, on implemented and instructed S-C-A associations and question which of these components are driven by dopaminergic modulations. Consequently, this part will define which parts of S-R learning are truly dopamine-driven. Finally, since reward value may often depend on social settings, we enquire on the effect of prosocial reward on the acquisition of S-R associations both when they are merely instructed and trained. We expect that the results will significantly further our understanding of association-driven learning.