The contribution of NMDA and AMPA receptors to persistent firing in the dorsolateral prefrontal cortex in working memory

In this dataset we compared the contribution of NMDA and AMPA receptors to persistent firing in the dorsolateral prefrontal cortex (dlPFC) of male macaque monkeys performing a delayed saccade to a memorized spatial location. We used iontophoresis to eject small amounts of glutamate receptor antagonists (APV for blocking NMDA-Rs, CNQX for blocking AMPA-Rs), aiming to perturb but not abolish neuronal activity. We found that both AMPA-Rs and NMDA-Rs contributed to persistent activity. Blockers of the NMDA-Rs decreased persistent firing associated with the memory of the neuron’s preferred spatial location but had comparatively little effect on the representation of the anti-preferred location. They therefore decreased the information conveyed by persistent firing about the memorized location. In contrast, AMPA-R blockers decreased activity elicited by the memory of both the preferred and anti-preferred location, with a smaller effect on the information conveyed by persistent activity. Our results provide new insights into the contribution of AMPA-Rs and NMDA-Rs to persistent activity during working memory tasks.