Our Quest
How does the brain change with age? More specifically, how do neural circuits — the networks of interconnected neurons that serve as the building blocks of brain function — adapt or decline over time?
The Jang Lab investigates how aging affects the brain’s ability to maintain balance in essential physiological processes and behaviors, with a particular focus on neural circuits. We are especially interested in the circuits that regulate thirst and fluid homeostasis, critical functions that become increasingly vulnerable in aging. Disruptions in these systems can lead to dehydration, frailty, poor health outcomes, and even mortality in older adults.
Our Approach
We combine molecular genetics, functional neural recording, behavioral analysis, and physiology to uncover how aging reshapes neural circuitry and homeostatic regulation. By studying these processes across multiple levels — from single neurons to whole-animal behavior and physiology — we aim to reveal the mechanisms that drive age-related decline.
Current Research Directions
1. How does thirst motivation change during normal aging?
Using thirst as a model, we study how motivation declines with advancing age at behavioral and neural circuit levels. We employ functional recording tools such as fiber photometry to monitor the activity of genetically defined neurons in awake animals and use optogenetic and chemogenetic manipulations to test novel interventions for age-related behavioral and physiological decline.
Relevant Publications:
Jang, H., Behne Sharma., A., Dan, U., Wong, J.H., Knight, Z.A. Garrison, J.L. (2024) Dysregulation of the fluid homeostasis system by aging. bioRxiv (in revision) doi.org/10.1101/2024.09.26.615271 (Link)
Ly, T., Oh, J.A., Sivakumar, N., Shehata, S., La Santa Medina, N., Huang, H., Liu, Z., Fang, W., Barnes, C., Dundar, N., Jarvie, B., Ravi, A., Barnhill, O.K., Li, C., Lee, G.R., Choi, J., Jang, H., Knight, Z.A. (2023) Sequential appetite suppression by oral and visceral feedback to the brainstem. Nature 624, 130–137. doi: 10.1038/s41586-023-06758-2, PMID: 37993711 (Link)
2. How does reproductive aging affect thirst circuitry?
Risks for cognitive impairment, cardiovascular disease, and metabolic disorders rise substantially in postmenopausal women. Our research investigates how reproductive aging in females influences thirst and fluid balance at both the behavioral and neural circuit levels, using an accelerated ovarian aging model.
Manuscript in preparation
3. How does aging disrupt neural control of fluid balance in nematodes?
We study how aging alters neural circuits that maintain hydration and fluid balance, focusing on water- and osmolality-sensing neurons in the nematode Caenorhabditis elegans. Leveraging its short lifespan, transparency, and powerful genetic tools, we combine neural recordings, optogenetics, and high-throughput behavioral assays to probe circuit function changes and test interventions in aged animals.
Relevant Publications:
Chen, Y., Jang, H., Spratt, P.W.E., Kosar S., Taylor. D.E., Essner, R.A., Bai, L., Leib, D.E., Kuo, T.-W., Lin, Y.-C., Patel, M., Subkhangulova, A., Kato, S., Feinberg, E.H., Bender, K.J., Knight, Z.A., Garrison, J.L. (2020) Soma-Targeted Imaging of Neural Circuits by Ribosome Tethering. Neuron 107(3);454-469. doi: 10.1016/j.neuron.2020.05.005, PMID:32574560 (Link)
Jang, H., Levy, S., Flavell, S.W., Mende, F., Latham, R., Zimmer M., Bargmann, C.I. (2017) Dissection of neuronal gap junction circuits that regulate social behavior in Caenorhabditis elegans. Proc Natl Acad Sci U S A 114(7):E1263-e1272. doi:10.1073/pnas.1621274114, PMID:28143932 (Link)
Long-Term Vision
Our goal is to advance fundamental understanding of how aging alters the brain and ultimately behavior and physiology at the organismal level and to develop strategies that promote resilience and healthy aging. By uncovering the neural and molecular basis of functional decline, we aim to inform new approaches to prevent dehydration-related complications and motivational decline and improve quality of life in late life.
Recruitment
The Jang Lab is recruiting motivated and passionate researchers at all levels, including part-time undergraduates, post-baccalaureate students, graduate students, and postdoctoral fellows, from diverse academic backgrounds in the biological sciences, neuroscience, veterinary medicine, and engineering. Interested applicants are encouraged to email a cover letter and CV to hjang@iastate.edu
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Last updated: September 2025