部門公開セミナー

日 時 2013年06月26日 16:00~17:00
場 所 生理研1階セミナー室
演 者 Ethan Bromberg-Martin(Laboratory of Sensorimotor Research, National Eye Institute, NIH)
演 題 Neural circuits for information seeking
要 旨

Humans and animals can be strongly motivated to seek advance information about future rewards. This motivation is likely to be supported by a pathway including lateral habenula neurons (LHb) and midbrain dopamine neurons (DA), which transmits a phasic reward signal reflecting the subjective value of getting information. This raises two major questions. (1) What neural signals does the brain use to compute the value of getting information? (2) Once it is computed, how is this value sent to the LHb-DA pathway to motivate behavior?

As a first step toward answering these questions, I will show that some LHb neurons receive a new type of tonic, sustained signal that anticipates the time of getting information about uncertain future rewards. This tonic signal could help to compute the value of getting information and to generate the phasic signal when information is received. I will also show preliminary evidence that the tonic and phasic information signals could be sent to the LHb-DA pathway by an output nucleus of the basal ganglia, and that these signals are enhanced by conditions that enhance information seeking behavior. These data suggest a possible role for the basal ganglia in computing the value of information and using it to motivate behavior.

(Selected publications) Bromberg-Martin ES, Hikosaka O. Lateral habenula neurons signal errors in the prediction of reward information. Nature Neuroscience (2011), Vol. 14, no. 9, pp. 1209-1216.

Bromberg-Martin ES, Hikosaka O. Midbrain dopamine neurons signal preference for advance information about upcoming rewards. Neuron (2009) Vol. 63, no. 1, pp. 119-126.

連絡先 橘 吉寿 生体システム研究部門 内線 7774