Tiffany Schmidt Understanding visual circuits using electrophysiology, behavior, & anatomy in mouse models

Research Interests

Light is an important and ever-present regulator of physiology and behavior and is involved in processes as wide ranging as daily hormonal oscillations, pattern vision, sleep, attention, and circadian photoentrainment. But how are light signals relayed to the brain to mediate these complex visual behaviors? In mammals, all light information reaches the brain via projections from the retinal ganglion cells (RGCs), of which there are ~20 subtypes in the retina. Therefore, to understand how light regulates behavior, we must understand: 1) How do RGC subtypes respond to different light stimuli? 2) What are the specific cellular targets of individual RGC subtypes in the brain? and 3) What are the functional contributions of RGC subtypes to defined visual behaviors?

We study these questions by looking at the role of RGC subtypes in specific visual functions. For example, the intrinsically photosensitive retinal ganglion cells (ipRGCs), which express the photopigment melanopsin, comprise five subtypes that drive a wide range of behaviors from circadian photoentrainment to contrast sensitivity for vision. The defined and quantitative behaviors in which these cells are involved and the myriad available genetic tools for the study of this system make it an ideal one in which to study the circuitry and role of ganglion cells in visual behavior. We do this using a range of techniques from electrophysiology, neuroanatomy, and behavioral approaches in various genetic mouse models.

Selected Publications

A noncanonical inhibitory circuit dampens behavioral sensitivity to light. Sonoda T, Li JY, Hayes NW, Chan JC, Okabe Y, Belin S, Nawabi H, and Schmidt TM. Science. 2020 May 1;368(6490):527-531.

Cellular properties of intrinsically photosensitive retinal ganglion cells during postnatal development. Lucas JA and Schmidt TM. Neural Development. 2019 August 30;14:8.

Distinct ipRGC subpopulations mediate light’s acute and circadian effects on body temperature and sleep. Rupp AC, Ren M, Altimus CM, Fernandez DC, Richardson M, Turek F, Hattar S, and Schmidt TM. eLife. 2019 July 23;8:e44358.

Light-dependent pathways for dopaminergic amacrine cell development and function. Munteanu T, Noronha KJ, Leung AC, Pan S, Lucas JA, and Schmidt TM. eLife. 2018 November 7;7:e39866.

Melanopsin Phototransduction Is Repurposed by ipRGC Subtypes to Shape the Function of Distinct Visual Circuits. Sonoda T, Lee SK, Birnbaumer L, and Schmidt TM. Neuron. 2018 August 22;99(4):754-767.e4.

View all publications by Tiffany Schmidt listed in the National Library of Medicine (PubMed). Current and former IBiS students in blue.