Nadira Yusif Rodriguez

All Publications

• Visual Simulation Is Supported by Sequential Monitoring in the Lateral Prefrontal Cortex JOURNAL OF COGNITIVE NEUROSCIENCE Ahuja, A., Yusif Rodriguez, N., Sheinberg, D. L., Desrochers, T. M. 2026; 38 (7): 1297-1306

  Abstract

  Visual simulation-a process that allows us to create complex internal models of the world-is essential for the completion of daily tasks, such as our morning commute. We can mentally track our progress along the route and make adjustments on the fly, all internally. Previous work has shown that complex visual simulations are supported by visuomotor regions across humans and nonhuman primates, but relatively little is known of the cognitive processes involved. We hypothesized that neural areas involved in sequential monitoring (i.e., keeping track of the state or step in an ordered series) are selectively active during visual simulation. A monotonic increase (ramping) in lateral prefrontal cortex (LPFC) activity has been previously shown to be necessary for executing nonmotor sequences. Therefore, to test the hypothesis, we examined LPFC activity in humans and a macaque monkey using fMRI while they performed a visual simulation task, "Planko." We found LPFC ramping across species that was specific to the visual simulation condition. These findings suggest that visual simulation tasks are supported by sequence monitoring regions across species, providing a foundation for understanding this complex and universal cognitive process.

  View details for DOI 10.1162/JOCN.a.2584

  View details for Web of Science ID 001806959900014

  View details for PubMedID 41790120

• Monkey Lateral Prefrontal Cortex Subregions Differentiate between Perceptual Exposure to Visual Stimuli. Journal of cognitive neuroscience Leaman, K., Rodriguez, N. Y., Ahuja, A., Basu, D., McKim, T. H., Desrochers, T. M. 2025; 37 (4): 802-814

  Abstract

  Each day, humans must parse visual stimuli with varying amounts of perceptual experience, ranging from incredibly familiar to entirely new. Even when choosing a novel to buy at a bookstore, one sees covers they have repeatedly experienced intermixed with recently released titles. Visual exposure to stimuli has distinct neural correlates in the lateral prefrontal cortex (LPFC) of nonhuman primates. However, it is currently unknown if this function may be localized to specific subregions within LPFC. Specifically, we aimed to determine whether the posterior fundus of Area 46 (p46f), an area that responds to deviations from learned sequences, also responds to less frequently presented stimuli outside of the sequential context. We compare responses in p46f to the adjacent subregion, posterior ventral area 46 (p46v), which we propose may be more likely to show exposure-dependent responses due to its proximity to novelty-responsive regions. To test whether p46f or p46v represent perceptual exposure, we performed awake fMRI on three male monkeys as they observed visual stimuli that varied in their number of daily presentations. Here, we show that p46v, but not p46f, shows preferential activation to stimuli with low perceptual exposure, further localizing exposure-dependent effects in monkey LPFC. These results align with previous research that has found novelty responses in ventral LPFC and are consistent with the proposal that p46f performs a sequence-specific function. Furthermore, they expand on our knowledge of the specific role of LPFC subregions and localize perceptual exposure processing within this broader brain region.

  View details for DOI 10.1162/jocn_a_02291

  View details for PubMedID 39785668