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Osten, P.

Publications and source records attributed to Osten, P..

3 recordsLinked to original sources

Distinct Cortical-Thalamic-Striatal Circuits Through the Parafascicular Nucleus

The thalamic parafascicular nucleus (PF), an excitatory input to the basal ganglia, is targeted with deep-brain-stimulation to alleviate a range of neuropsychiatric symptoms. Furthermore, PF lesions disrupt the execution of correct motor actions in uncertain environments. Nevertheless, the circuitry of the PF and its contribution to action selection are poorly understood. We find that, in mice, PF forms the densest subcortical projection to the striatum. This projection arises from transcriptionally- and physiologically-distinct classes of PF neurons that are also reciprocally connected with functionally-distinct cortical regions, differentially innervate striatum neurons, and are not synaptically connected in PF. Thus, mouse PF contains heterogeneous neurons that are organized into parallel and independent associative, limbic, and motor circuits. Furthermore, these subcircuits share motifs of cortical-PF-cortical and cortical-PF-striatum organization that allow each PF subregion, via its precise connectivity with cortex, to coordinate diverse inputs to striatum.

neuroscience

Radial glial lineage progression and differential intermediate progenitor amplification underlie striatal compartments and circuit organization

The circuitry of the striatum is characterized by two organizational plans: the division into striosome and matrix compartments, thought to mediate evaluation and action, and the direct and indirect pathways, thought to promote or suppress behavior. The developmental origins of and relationships between these organizations are unknown, leaving a conceptual gap in understanding the cortico-basal ganglia system. Through genetic fate mapping, we demonstrate that striosome-matrix compartmentalization arises from a lineage program embedded in lateral ganglionic eminence radial glial progenitors mediating neurogenesis through two distinct types of intermediate progenitors (IPs). The early phase of this program produces striosomal spiny projection neurons (SPNs) through fate-restricted apical IPs (aIPSs) with limited capacity; the late phase produces matrix SPNs through fate-restricted basal IPs (bIPMs) with expanded capacity. Remarkably, direct and indirect pathway SPNs arise within both aIPS and bIPM pools, suggesting that striosome-matrix architecture is the fundamental organizational plan of basal ganglia circuitry organization.

neuroscience

A High Resolution Whole Brain Imaging Using Oblique Light Sheet Tomography

Present light sheet fluorescence microscopes lack the wherewithal to image the whole brain (large tissues) with uniform illumination/detection parameters and high enough resolution to provide an understanding of the various aspects of neuroanatomy. To overcome this, we developed an oblique version of the light sheet microscope (Oblique Light Sheet Tomography, OLST) that includes a high magnification objective and serial sectioning, for volumetric imaging of the whole mouse brain at high spatial resolution at constant illumination/detection. We developed a novel gelatin based re-embedding procedure that makes the cleared brain rigid so that it can sectioned using our integrated microtome. Here, we characterize OLST and show that it can be used to observe dendritic morphology, spines and follow axons over a few mm in the mouse brain.

neuroscience