Evaluation of the hypothesis that phasic dopamine constitutes a cached-value signal
Name:
Publisher version
View Source
Access full-text PDFOpen Access
View Source
Check access options
Check access options
Date
2018Journal
Neurobiology of Learning and MemoryPublisher
Elsevier Inc.Type
Article
Metadata
Show full item recordAbstract
The phasic dopamine error signal is currently argued to be synonymous with the prediction error in Sutton and Barto (1987, 1998) model-free reinforcement learning algorithm (Schultz et al., 1997). This theory argues that phasic dopamine reflects a cached-value signal that endows reward-predictive cues with the scalar value inherent in reward. Such an interpretation does not envision a role for dopamine in more complex cognitive representations between events which underlie many forms of associative learning, restricting the role dopamine can play in learning. The cached-value hypothesis of dopamine makes three concrete predictions about when a phasic dopamine response should be seen and what types of learning this signal should be able to promote. We discuss these predictions in light of recent evidence which we believe provide particularly strong tests of their validity. In doing so, we find that while the phasic dopamine signal conforms to a cached-value account in some circumstances, other evidence demonstrate that this signal is not restricted to a model-free cached-value reinforcement learning signal. In light of this evidence, we argue that the phasic dopamine signal functions more generally to signal violations of expectancies to drive real-world associations between events. © 2017Keyword
model-free reinforcement learning algorithmphasic dopamine signal
Conditioning (Psychology)
Dopamine
Reward
Identifier to cite or link to this item
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039556743&doi=10.1016%2fj.nlm.2017.12.002&partnerID=40&md5=6d437789206a4e3a7054433ed0ece475; http://hdl.handle.net/10713/8781ae974a485f413a2113503eed53cd6c53
10.1016/j.nlm.2017.12.002