Haijiang Cai, Ph.D.

Associate Professor
Haijiang Cai, Ph.D.

Office: Rm 427 Gould-Simpson
Mailing Address:
Department of Neuroscience
University of Arizona
GS 611, 1040 E. 4th St. PO Box 210077
Tucson, AZ 85721-0077


B.S. USTC, 2001; Ph.D. USC, 2007; Postdoc, Caltech, 2008-2015.


We are studying neural circuit mechanisms of animal behaviors in health and disease, with a focus on understanding how the neural circuits regulate eating and emotional behaviors such as fear, anxiety, and depression.

We use multidisciplinary approaches including transgenic mice, optogenetics, chemogenetics, in vivo calcium imaging, various behavioral assays, brain slice electrophysiology, virus and non-virus based neuronal tracing, stereotaxic injection and surgery,  immunohistology and microscopy imaging.

1. Interactions of the eating and emotion neural circuits. One fascinating and important phenomenon (or problem) in neuroscience is that many neuronal disorder are co-morbid. For example, most eating disorder patients also have emotional disorders such as depression and anxiety. However, little is known about the neurobiology underlying eating disorders, even less is known about their relationship with emotional disorders. Recently, we have identified a specific population of neurons in the central extended amygdala (CEA), a region known for emotion control, that play important roles in regulating eating behaviors. This result has opened a unique door to understanding the interactions of eating and emotion at the circuits level. [Arizona Public Media: Episode 194: Researching eating disorders with lab mice]

Eating Emotion Gif Description

2. Brain circuits for gut-brain communication.  Satiation signals such as CCK are released in the gastrointestinal tract (GI tract) during a meal. They activate the vagus nerves to reach the central brain nucleus tractus solitarius (NTS), and then to the parabrachial nucleus (PBN). PBN sends information further to CEA and other nucleus to stop eating. Other anorexigenic signals including visceral malaise and bitter tastant, are also using similar pathways to reach the brain regions to mediate various behavioral responses. Interestingly, CEA neurons represent the first inhibitory relay in this pathway. Therefore, functional circuits mapping using c-Fos cannot go further downstream of this pathway directly. The genetic identification of CEA neurons provided us a fascinating tool to investigate the gut-brain communication in a specific way and to determine the downstream brain regions after CEA.

3. Eating and emotion circuits in energy balance, metabolism, and obesity.  More and more evidences suggest that the neural circuits regulate emotion and acute eating behaviors also contribute to the long term homeostasis of energy balance, metabolism, and body weight. Do CEA neural circuits also regulate obesity, a more and more serious global health problem in modern society? The neurons in the hypothalamic nuclei, including lateral hypothalamus, arcuate nucleus, and paraventricular hypothalamic nucleus, have been well demonstrated to be involved in acute eating regulation and long term energy homeostasis. What is the relationship of the CEA eating circuits to the circuits in the hypothalamic nuclei?

SELECTED PUBLICATIONS (click here for the complete list)

  1. Schnapp WI, Kim J, Wang Y, Timilsena S, Fang C, Cai H. Development of activity-based anorexia requires PKC-δ neurons in two central extended amygdala nuclei. Cell Rep. 2024 Mar 26;43(3):113933. doi: 10.1016/j.celrep.2024.113933. Epub 2024 Mar 8. PubMed PMID: 38460131.
    News & Media: UA News
  2. Sanchez MR, Wang Y, Cho TS, Schnapp WI, Schmit MB, Fang C, Cai H. Dissecting a disynaptic central amygdala-parasubthalamic nucleus neural circuit that mediates cholecystokinin-induced eating suppression. Mol Metab. 2022 Jan 20;58:101443. doi: 10.1016/j.molmet.2022.101443. [Epub ahead of print] PubMed PMID: 35066159.
    News & Media: UA News | Daily Wildcat / Arizona Public Media (AZPM) | Arizona PBS | KVOA News 4 Tucson | ScienceDaily | EurekAlert! | Neuroscience News | Brainerd Dispatch | Times Now |
  3. Zhang-Molina C, Schmit MB, Cai H. Neural Circuit Mechanism Underlying the Feeding Controlled by Insula-Central Amygdala Pathway. iScience. 2020 Apr 5;23(4):101033. doi: 10.1016/j.isci.2020.101033. [Epub ahead of print] PubMed PMID: 32311583; PubMed Central PMCID: PMC7168768.
  4. Wang Y, Kim J, Schmit MB, Cho TS, Fang C, Cai HA bed nucleus of stria terminalis microcircuit regulating inflammation-associated modulation of feeding. Nat Commun. 2019 Jun 24;10(1):2769. doi: 10.1038/s41467-019-10715-x. PubMed PMID: 31235690.
    News & MediaUA News | Daily Wildcat | Brain & Behavior Research Foundation News | KGUN-TV 9 News | Arizona Public Media (AZPM) | ScienceDaily | EurekAlert!Neuroscience News | Daily Mail | Genetic Engineering & Biotechnology News
  5. Cai H, Haubensak W, Anthony TE, Anderson DJ. Central amygdala PKC-δ(+) neurons mediate the influence of multiple anorexigenic signals. Nat Neurosci. 2014 Sep;17(9):1240-8. doi: 10.1038/nn.3767. Epub 2014 Jul 27. PubMed PMID: 25064852; PubMed Central PMCID: PMC4146747.
    News & Media: New York Times: A mouse switch turns off appetite | BBC: Brain cells can suppress appetite, study in mice shows
  6. Haubensak W, Kunwar PS*, Cai H*, Ciocchi S*, Wall NR, Ponnusamy R, Biag J, Dong HW, Deisseroth K, Callaway EM, Fanselow MS, Lüthi A, Anderson DJ. Genetic dissection of an amygdala microcircuit that gates conditioned fear. Nature. 2010 Nov 11;468(7321):270-6. doi: 10.1038/nature09553. PubMed PMID: 21068836; PubMed Central PMCID: PMC3597095.  *equal contribution
  7. Cai H, Reim K, Varoqueaux F, Tapechum S, Hill K, Sørensen JB, Brose N, Chow RH. Complexin II plays a positive role in Ca2+-triggered exocytosis by facilitating vesicle priming. Proc Natl Acad Sci U S A. 2008 Dec 9;105(49):19538-43. doi: 10.1073/pnas.0810232105. Epub 2008 Nov 25. PubMed PMID: 19033464; PubMed Central PMCID: PMC2614796.


  • NROS 418 (Spring): Fundamental Principles in Systems Neuroscience
  • NROS 418 Online (Fall, 2022 & 2023): Fundamental Principles in Systems Neuroscience
  • NROS 435 (Fall): Complex Behavioral, Cognitive and Emotional Disorders
  • NRSC 560 (Spring): Systems Neuroscience. Neuroscience GIDP, Course Coordinator: Andrew Fuglevand.


  • Matthew Schmit, Graduate Student, Neuroscience GIDP
  • Wesley Schnapp, Graduate Student, Neuroscience GIDP
  • Masa Miscevic, Graduate Student, Physiological Sciences GIDP
  • Shivani Mann, Postdoc
  • Marco Conteras, Research Scientist
  • Anna Fang, Research Specialist
  • Ananya Nigam, Undergraduate Student
  • Hannah Vu, Undergraduate Student
  • Cassidy Johnson, Undergraduate Student
  • Sayujya Timilsena, Undergraduate Student
  • Elise Bouchal, Undergraduate Student
  • Vivianna Pederson, Undergraduate Student
  • Emma Stewart-Nava, Undergraduate Student

     Former members

  • Postdocs: Yong Wang (2016-2018), Marina Rodriguez Sanchez (2021)
  • Graduate Students: Andrew Tubbs (2016 rotation), Hannah Dollish (2017 rotation), Gowri Somasekhar (2020 rotation), Emily McDonald (2022 rotation)
  • Technicians: JungMin Kim (2016-2018), Ross Mansouri-Rad (2017-2018), Mauricio Serna (2021)
  • Undergraduate Students: John Kim (2016), Alison Kath (2016), Tiffany Cho (2017-2019), Tahia Hanseen (2018-2020), Kevin Vo (2018-2020), Mayra Rivera (2019-2021), Gizem Ozturk (2020-2021), Veena Raghuraman (2021)
  • High School Students: Makenna Anderson (2017-2018)

Cai lab, 2018