http://www.benjamintsaunders.com/home daily 1.0 2021-05-30 http://www.benjamintsaunders.com/lab-cover-page-test daily 0.75 2017-06-19 http://www.benjamintsaunders.com/research daily 0.75 2021-05-30 https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58bf4112e58c62f7844210fa/1488929067605/ Research Here I will condition cues to optogenetic VTA DA stimulation and track cue-evoked calcium activity in axons in the nucleus accumbens and dorsolateral striatum across training. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58be1d186a496390295d0d8a/1488855201820/Website+Research+image3.png Research Fiber photometry allows for the measurement of calcium signaling, as a proxy for neural activity, via genetically-encoded calcium indicators (GCaMP6). Here photometry was combined with optogenetic manipulation of the same neurons, during Pavlovian conditioning. Saunders et al., in prep. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58be163659cc6866d2231895/1488854732600/ Research Imaging calcium fluorescence using miniature microscopes makes it possible to assess single neuron activity in freely moving animals. Shown is an unprocessed movie of GABAergic neurons in the midbrain of a mouse engaged in cocaine-related behaviors. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58bf4e612e69cfc931187024/1488932582736/Website+Research+image6.png Research Heterogeneous DA neuron activity will be further explored with projection-defined imaging studies. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58be1aa6bebafbf4b3d995b6/1488931701039/Website+Research+image4.png Research Current technology requires tethering to a data acquisition source, but new microscopes are under development that will allow for wireless recordings, which I will use in the future for imaging in rats. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58bdf86eebbd1a862aa7e2b8/1488844935565/ Research Neurons releasing dopamine arise from deep in the brain and project to a variety of regions, including the striatum, where their signaling influences reward-related processes. Shown is a cartoon of dopamine neurons in the rat brain, but the primary circuits are similar in humans. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58bdd7602994cad02a74614f/1497993733656/ Research Heterogeneous cue-evoked motivational signals from distinct dopamine (DA) neuron projections. Ventral striatal dopamine neurons promote "attraction" to conditioned cues (CS), while dorsal striatal dopamine neurons promote movement. Dopamine neuron terminals in the striatum are visualized here in green. Saunders et al., in prep (2016 SFN Poster). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58bf0ffd37c581850ed7b64a/1488917011446/High+Zoom+Combined.jpg Research http://www.benjamintsaunders.com/about daily 0.75 2018-06-25 https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/57a775899f745640fd601171/1470592434470/ About https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/57a776706a4963e386704c03/1470592634592/ About https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/57891583c534a59362a682b5/1468619154696/ About https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58be010444024341e9579a7f/1488990875733/mPFC+Purple+DAPI.jpg About http://www.benjamintsaunders.com/gallery daily 0.75 2017-03-11 https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c04fd7d1758ee4ddded9e7/1489255310506/ Gallery Image of the ventral tegmental area in the midbrain. Neurons (blue) were co-transfected with viruses containing GCaMP6f (green) and ChrimsonR-tdTomato (red). In this preparation, they overlap with neurons stained for tyrosine hydroxylase (white). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c055cc8419c2bd8ffb8d79/1489257472730/ Gallery Whole brain coronal section image containing the midbrain. Dopaminergic neurons are shown with a stain for tyrosine hydroxylase (red). Neurons in the substantia nigra expressing ChR2-eYFP (green) from a infusion of a retrograde virus in the dorsal striatum. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0443644024364325c1ecf/1489250087621/ Gallery Midbrain neurons (blue). ChR2-eYFP expression (green) is restricted to tyrosine hydroxylase containing neurons (red), producing a mostly yellow overlay. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c04b14db29d64f400cf97b/1489250271421/ctb7_CortexDSProjections_647.jpg Gallery Neurons in the dorsal prefrontal cortex (pink), retrogradely labeled with cholera toxin from the dorsal striatum. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c046d09de4bbc4172528d9/1489250320726/ Gallery Lateral orbitofrontal cortex neurons expressing ChR2-eYFP (green). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c052e72994caf6c0a898ee/1489257484241/OFC20xbrighter.jpg Gallery Orbitofrontal cortex neurons (dark blue) expressing ArchT3.0-eYFP (light blue). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c04769725e2582ddcb80f0/1489257734980/ Gallery Whole brain coronal section image. Axon terminals from neurons in the substantia nigra in the dorsal striatum (green, left side). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c046f65016e10ae1bcbcce/1489252673945/ Gallery Neurons in the medial prefrontal cortex (purple) expressing GCaMPgf (green). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0561f37c581ad43105f7f/1489254733423/ Gallery Dorsal striatum image. Neurons (light blue) surrounded by axon terminals expressing ChR2-eYFP (yellow). Neurons co-labeled for c-fos (pink) were activated by an experimental manipulation. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c053a09de4bbc873feb7b1/1489257531120/ Gallery Image of the medial ventral tegmental area. Dopaminergic neurons, expressing tyrosine hydroxylase (pink), co-express ChR2-eYFP (light blue) in this preparation. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c043e1b8a79b05f46224e1/1489254542298/ Gallery 3-color image of the dorsal striatum. Neurons (blue) are surrounded by axon terminals expressing ChR2-eYFP (green). In this preparation, they co-localize with terminals stained for tyrosine hydroxylase (red), producing a mostly yellow overlay. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c04729d2b8578f530c2e31/1489254557595/ Gallery Dorsomedial striatum image. Neurons (yellow) surrounded by Arch-T3.0-eYFP expressing axon terminals (pink) projecting from the orbitofrontal cortex. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0555837c581ad431051db/1489254916938/ Gallery Nucleus accumbens core image. Neurons (blue) surrounded by axon terminals expressing ChR2-eYFP (green) that overlap with terminals stained for tyrosine hydroxylase (red). https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0469d725e2582ddcb7286/1489250213742/ Gallery Neurons in the substantia nigra stained for tyrosine hydroxylase (red), expressing ChR2-eYFP from a retrograde viruse injected in the dorsal striatum. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0478b5016e10ae1bcc837/1489254584358/ Gallery Axonal fibers expressing ChR2-eYFP (green) traversing anterior midbrain. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0436329687fdfb7c60ec9/1489249430721/Ben1-VTA_40x.jpg Gallery Midbrain neurons expressing ChR2-eYFP (40x confocal image) https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0533359cc688deedcecd6/1489255722001/ Gallery Whole brain coronal section image. Axon terminals from neurons in the orbitofrontal cortex expressing ChR2-eYFP (green) in the thalamus and basolateral amygdala. https://static1.squarespace.com/static/5509bba2e4b06a37a307de4f/t/58c0569a3a0411f38cb56227/1489000211125/GCaMP%26Chrimson.jpg Gallery http://www.benjamintsaunders.com/lab-test-page daily 0.75 2017-05-07 http://www.benjamintsaunders.com/new-page daily 0.75 2017-06-19