Citation

Berditchevskaia A, Cazé RD, Schultz SR. Sci. Rep. 2016; 6: e27389.

Affiliation

Department of Bioengineering and Centre for Neurotechnology, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK.

Copyright

(Copyright © 2016, Nature Publishing Group)

DOI

10.1038/srep27389

PMID

27272438

Abstract

In recent years, simple GO/NOGO behavioural tasks have become popular due to the relative ease with which they can be combined with technologies such as in vivo multiphoton imaging. To date, it has been assumed that behavioural performance can be captured by the average performance across a session, however this neglects the effect of motivation on behaviour within individual sessions. We investigated the effect of motivation on mice performing a GO/NOGO visual discrimination task. Performance within a session tended to follow a stereotypical trajectory on a Receiver Operating Characteristic (ROC) chart, beginning with an over-motivated state with many false positives, and transitioning through a more or less optimal regime to end with a low hit rate after satiation. Our observations are reproduced by a new model, the Motivated Actor-Critic, introduced here. Our results suggest that standard measures of discriminability, obtained by averaging across a session, may significantly underestimate behavioural performance.

Language: en