Distinct lateral prefrontal regions are organized in an anterior-posterior functional gradient

The dorsolateral prefrontal cortex (DLPFC) is composed of multiple anatomically-defined regions involved in higher-order cognitive processes, including working memory and selective attention. It is organized in an anterior-posterior global gradient, where posterior regions track changes in the environment, while anterior regions support abstract neural representations. However, whether the global gradient results from a smooth gradient that spans regions, or an overall trend emerging from the organized arrangement of functionally distinct regions is unknown. Here, we provide evidence to support the latter, by analyzing single-neuron activity along the DLPFC of non-human primates trained to perform a memory-guided saccade task with an interfering distractor. Additionally, we show that the posterior DLPFC plays a particularly important role in working memory, in sharp contrast with the lack of task-related responses in the anterior DLPFC. Our results validate the functional boundaries between anatomically-defined DLPFC regions and highlight the heterogeneity of functional properties across regions.