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Dawn M. Blitz

Biographical Information

Generating an appropriate behavior requires that neural circuits alter their output in response to changes in the internal (e.g. hungry vs. sated, stressed vs. calm) and external (e.g. food or predator nearby) environment. Changes in circuit output result largely from sensory input and input from other regions of the central nervous system (CNS). These inputs commonly converge onto descending modulatory projection neurons, which then integrate the incoming information and in turn alter the intrinsic properties of individual neurons and the strength of connections among circuit neurons. We aim to identify mechanisms of integration at the level of descending inputs and determine how the resulting activity in the projection neurons enables the selection and generation of a specific motor circuit output, specific muscle activity and ultimately an appropriate behavior.

In order to achieve this goal we are using a model system, the crustacean stomatogastric nervous system in the Jonah crab, Cancer borealis. While the circuits underlying rhythmic behaviors across species have many similarities, the model system we use is unusually accessible due to the small number of neurons and their large size, enabling detailed cellular-level studies of systems-level questions. Using electrophysiological techniques (current-, voltage-, and dynamic clamp recording methods, extracellular nerve recordings, intracellular recordings from identified neuron cell bodies, axons and muscle fibers; single cell photoablation) and anatomical techniques (immunocytochemistry, nerve back-fills, single neuron dye-fills, epi-fluorescence and confocal microscopy) we can take advantage of this small system to address our questions.

Selected Publications

• Snyder RR, Blitz DM (2022) Multiple intrinsic membrane properties are modulated in a switch from single- to dual-network activity. J Neurophysiol, 128:1181-1198.
• Fahoum, S-RH, Blitz DM (2021) Neuronal switching between single- and dual-network activity via modulation of intrinsic membrane properties. J Neurosci, 41: 7848-7863.
• Blitz DM, Christie AE, Cook A, Dickinson PS, Nusbaum MP (2019) Similarities and differences in circuit responses to applied Gly¹-SIFamide and peptidergic (Gly¹-SIFamide) neuron stimulation. J Neurophysiol, 120:952-972. (Cover)
• Nusbaum MP, Blitz DM, Marder E (2017) Functional consequences of neuropeptide/small molecule cotransmission. Nat Rev Neurosci, 18(7):389-403.
• White RS, Spencer RM, Nusbaum MP, Blitz DM (2017) State-dependent sensorimotor gating in a rhythmic motor system. J Neurophysiol, 118:2806-2818.
• Blitz DM (2017) Circuit feedback increases activity level of a circuit input through interactions with intrinsic properties. J Neurophysiol, 118:949-963.
• Blitz DM, Pritchard AE, Latimer JK, Wakefield AT (2017) Muscles innervated by a single motor neuron exhibit divergent synaptic properties on multiple time scales. J Exp Biol, 220:1233-1244.
• Spencer RM, Blitz DM (2016) Network feedback regulates motor output across a range of modulatory neuron activity. J Neurophysiol 115(6):3249-3263.
• Swallie SE, Monti AM, Blitz DM (2015) Anatomical organization of multiple modulatory inputs in a rhythmic motor system. PLoS ONE 10:e0142956.

Courses Taught

• BIO 161: Human Physiology
• BIO 305: Human Physiology
• BIO 400: Capstone Seminar in Neural Plasticity
• BIO 491: Seminar in Biology: Neural Control of Movement and other topics
• BIO 710: Seminar in Biology: Neural Plasticity; Endocannbinoid Signaling in the Nervous System; and other topics