Biology subjects

Mendelsohn, A.

Publications and source records attributed to Mendelsohn, A..

2 recordsLinked to original sources

bioRxiv2024

Segregated basal ganglia output pathways correspond to genetically divergent neuronal subclasses

The basal ganglia control multiple sensorimotor behaviors though anatomically segregated and topographically organized subcircuits with outputs to specific downstream circuits. However, it is unclear how the anatomical organization of basal ganglia output circuits relates to the molecular diversity of cell types. Here, we demonstrate that the major output nucleus of the basal ganglia, the substantia nigra pars reticulata (SNr) is comprised of transcriptomically distinct subclasses that reflect its distinct progenitor lineages. We show that these subclasses are topographically organized within SNr, project to distinct targets in the midbrain and hindbrain, and receive inputs from different striatal subregions. Finally, we show that these mouse subclasses are also identifiable in human SNr neurons, suggesting that the genetic organization of SNr is evolutionarily conserved. These findings provide a unifying logic for how the developmental specification of diverse SNr neurons relates to the anatomical organization of basal ganglia circuits controlling specialized downstream brain regions.

neuroscience↗

bioRxiv2019

Building a story: coherent narrative formation relies on functional connectivity in posterior cortex and frontoparietal networks

Narratives are embedded in human experience, enabling the integration and communication of large quantities of accumulated information. Despite the ubiquity of this deeply rooted ability, the neural networks involved in narrative formation are yet unclear. Building on literary and philosophical definitions of narrative, we explored brain networks that differentially coactivated while individuals were presented with either coherent or incoherent narratives. Using movie scenes presented in a functional MRI environment, either in their correct or reversed order, we found that regions in the posterior cortex and frontoparietal networks were preferentially co-activated during coherent narrative formation. Moreover, whereas coactivation patterns of posterior cortex converged across conditions over time, the frontoparietal network remained constantly higher in the coherent narrative condition. We suggest that processing and integrating accumulating information is supported by functional coupling of posterior cortical networks, whereas the frontoparietal network serves to maintain the coherence and causal relations that underpin plot comprehension.

neuroscience↗