The transitive inference task to study the neuronal correlates of memory-driven decision making: a monkey neurophysiology perspective

: A vast amount of literature agrees that rank-ordered information as A>B>C>D>E>F is mentally represented in spatially organized schemas after learning. This organization significantly influences the process of decision-making, using the acquired premises., i.e. deciding if B is higher than D is equivalent to comparing their position in this space. The implementation of non-verbal versions of the transitive inference task has provided the basis for ascertaining that different animal species explore a mental space when deciding among hierarchically organized memories. In the present work, we reviewed several studies of transitive inference that highlighted this ability in animals and the underlying cognitive processes, and developed animal models to study which are the main neural structures supporting this ability, and investigated which are the underlying neuronal mechanisms. Then we discuss how non-human primates represent an excellent model for future studies, providing ideal resources for a better understanding of the neuronal correlates of decision-making in transitive inference tasks.