Project Details
Projekt
State-Dependent Neuronal Variability in Primate PFC During Numerical Judgment
Applicant
Professor Dr. Andreas Nieder
Subject Area
Cognitive, Systems and Behavioural Neurobiology
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 437610067
Humans and animals share a fundamental, non-symbolic number system that enables both the perception of quantity and the production of specific numbers of self-generated actions. This capacity is critical not only for formal mathematical reasoning but also for adaptive behavior in natural environments. In the first funding phase, we uncovered neuronal mechanisms in the primate brain that link perceived numbers to the number of self-generated actions. Building on these findings, the current project aims to investigate a largely understudied but essential feature of higher cognition: the role of trial-to-trial variability in prefrontal cortex (PFC) neuronal activity during numerical decision-making. Rather than representing mere noise, we hypothesize that this variability enables cognitive flexibility by supporting dynamic coding strategies and adaptive network states. Although neural variability in the PFC is well-documented, its specific computational function in shaping numerical judgments and behavioral adaptability remains unclear. To address this, we will study rhesus macaques (Macaca mulatta) performing behaviorally demanding delayed-response tasks that require numerical estimation, working memory, and volitional motor output. These include a complex motor counting task developed during the first funding phase. We will combine behavioral analysis with high-resolution neuronal recordings to examine how both spontaneous and experimentally modulated variability in PFC activity influences task performance. In particular, we will assess the contribution of neuromodulatory systems, such as dopamine, to variability-driven flexibility. By linking neuronal variability to cognitive function, this project will shed new light on the mechanisms enabling adaptive numerical cognition. Comparative analyses across species within the Research Unit will further elucidate shared and divergent strategies for behavioral flexibility. Our primate model serves as a crucial bridge between human cognitive neuroscience and mechanistic studies in rodents, leveraging interdisciplinary collaboration to advance our understanding of prefrontal cortex function.
DFG Programme
Research Units
