A cortical substrate for memory-guided orienting in the rat
Jeffrey C. Erlich, Max Bialek, and Carlos D. Brody Neuron 72(2):330-343, 2011
Have you ever heard of the rat frontal eye fields?
We hadn’t either. But a literature search revealed a small but fascinating set of papers that suggested that the rat might have a frontal cortical structure homologous to the primate frontal eye field (FEF)! Why is this exciting? Because the FEF is a key element in the circuit for spatial attention & memory and for the planning/preparation and execution of orienting movements. We want to understand the neural mechanisms of these behavioral phenomena using the rat as an animal model, so the “rat FEF” might be a good place to start.
We set out to test whether this structure, which we call the frontal orienting field (FOF), was involved in
memory-guided orienting. In this task subjects are presented with an auditory cue that indicates which way they should orient to obtain a reward. However, the subjects are only allowed to respond after a delay. The task thus separates the stimulus from the response in the tradition of classic memory-guided tasks. In primates the FEF is essential for successful performance on these types of tasks. Using pharmacology and electrophysiology we demonstrated that the rat FOF is required for memory-guided orienting and that neural activity in the FOF predicts the upcoming orienting motion of the rat!
First-author Jeff Erlich is now faculty at NYU-Shanghai.