Topic: unsigned reward prediction error

Signaling that an expectation has been violated is a central function of the nervous system. This signal may come in the form of a reward prediction error, which can either be signed, reflecting the value of an unexpected outcome, or unsigned, reflecting the capture of attention. The role of dorsolateral prefrontal cortex (dlPFC), known to carry both value and attention related signals, in communicating when expectations are violated is not well understood [1,2]. How are unexpected outcomes signaled in dlPFC? To address this question, we trained macaque monkeys to view displays consisting o