Contextual modulations of value and decision making
How does the context in which a decision is taken influence the decision variables that capture attention and the choices that are made?
The way in which the value of an option is assessed may depend not only on its intrinsic rewarding properties but also on the immediate and long-term context of available alternatives against which it is assessed. Such factors may also influence the decision variables that come to command attention in complex environments.
We have recently found that the medial part of the orbitofrontal cortex (OFC) is critical to allow animals to appropriately compare the available options and to make rational decisions in the face of distracting alternatives. Unlike lesions to lateral OFC, damage to medial OFC does not affect stimulus-outcome learning. Instead, animals become poor at making decisions when the values of the available options are close together. This was particularly marked when the second best option was markedly better than the worst one or when all three options had a high value. Such a pattern of impairments suggests that the medial OFC is critical to focus attention on the relevant information in a complex environment.
Current research focuses on:
- Electrochemical studies of relative value
- FMRI and lesion studies of the brain structures involved in comparisons between relevant decision variables during decision making
Selected Key Papers
- Noonan MF, Walton ME, Behrens TE, Sallet J, Buckley MJ, Rushworth MF (2010). Separate value comparison and learning mechanisms in macaque medial and lateral orbitofrontal cortex. Proceedings of the National Academy of Sciences, 107(47): 20547-20552