Past work has made conflicting proposals about the mechanisms underlying instructed reinforcement learning (RL)specifically,that prefrontal cortex, representing instruction, either biases, attenuates, or overrides learning signals in the brain. Weleverage the sensitivity of pattern-similarity analysis of fMRI data to distinguish between the qualitative features of theseaccounts. Participants learn the value of six novel stimuli after receiving false information that one is of high value. Wetrack markers of value learning in visual cortex during a value-independent perceptual judgement task presented betweenintervals of RL. We predict that with learning, the correlation between activation patterns for similarly valued stimuli willincrease. To characterize influences on learning, we examine how the rate at and direction in which these patterns changein similarity will be influenced by explicit instruction about stimulus value. This work will help us identify the principlecognitive and neural mechanisms underlying instructed RL.