Suelynn Ren

Program: Neurosciences

Current advisor: Adam Kepecs, PhD

Undergraduate university: McGill University

Research summary
The identification of distinct cell types in frontal cortex is essential to realize a mechanistic understanding of cognitive function. Pyramidal neurons in layer 5 constitute the main output to subcortex and project outside of the cortico-thalamic system to distribute information to specialized structures, but a blueprint for the different output pathways is lacking. Here, we set out to understand the architectural logic of subcortical projection cell types in the rat orbitofrontal cortex. We used a combination of viral tracing, single-cell resolution projection mapping and RNA sequencing to comprehensively map subcortical outputs and established correspondence across these different modalities. At a single neuron resolution, we characterize the connectivity of ~450,000 neurons and demonstrate that most neurons project to a single subcortical target, representing a dedicated line. These connectivity-defined projection neurons preferentially reside in intermediate sublayers beyond the classical layer 5a and 5b distinction, and express unique sets of genes, including transcription factors and surface receptors. Taken together, subcortical projection neurons in orbitofrontal cortex represent distinct neuronal cell types and partitioned streams of information, an architecture that hints at dissociable, parallel processes in economic decision making.


Graduate publications