Data from: Control of entropy in neural models of environmental state

Humans and animals construct internal models of their environment in order
to select appropriate courses of action. The representation of uncertainty
about the current state of the environment is a key feature of these
models that controls the rate of learning as well as directly affecting
choice behaviour. To maintain flexibility, given that uncertainty
naturally decreases over time, most theoretical inference models include a
dedicated mechanism to drive up model uncertainty. Here we probe the
long-standing hypothesis that noradrenaline is involved in determining the
entropy, and thus flexibility, of neural models. Pupil diameter, which
indexes neuromodulatory state including noradrenaline release, predicted
increases (but not decreases) in entropy in a neural state model encoded
in human medial orbitofrontal cortex, as measured using multivariate
functional MRI. Activity in anterior cingulate cortex predicted pupil
diameter. These results provide evidence for top-down, neuromodulatory
control of entropy in neural state models.