A photo of Diego Fernandez.

Diego Fernandez, PhD

  • Member, Division of Pediatric Ophthalmology
  • Assistant Professor, UC Department of Ophthalmology
  • Science of Light Center



I’m a neuroscience researcher studying sensory biology and circadian rhythms. Our lab is broadly interested in understanding how the body and brain encode environmental stimuli, such as daily changes in light and feeding patterns, to timely coordinate physiology and behavior.

I obtained my PhD from the University of Buenos Aires, Argentina. My work identified ischemic conditioning as a strategy to ameliorate the damage caused by ischemic retinal pathologies, such as diabetic retinopathy. My doctoral work earned local and international awards, including the POEN Award and the Eduardo Soto Award, in recognition of the best national works in ophthalmology and neuroscience, respectively. In addition, I had the honor of receiving the Ricardo Miledi Neuroscience Training Program fellowship.

Following up on my interest in studying retina-related processes, I joined the laboratory of Dr. Samer Hattar at Johns Hopkins University with the support of the Pew Latin American Postdoctoral Fellows Award. My postdoctoral work revealed that parallel retina-brain circuits mediate the direct effects of light on learning and mood in mice.

I then joined the National Institutes of Health (NIH)/National Institute of Mental Health (NIMH) as a staff scientist and then as an associate scientist, where I started a new line of research that revealed a novel link between retinal and feeding circuits that control the integration of environmental time cues to affect metabolism and behavior.

Since joining Cincinnati Children’s in 2023, I have been developing novel lines of research aimed at investigating the mechanisms that guide the assembly and maturation of circuits linking sensory and circadian systems. Information obtained from this multidisciplinary approach becomes relevant for investigating the basis of disorders linked to deleterious environmental factors, such as light pollution, thus, expanding the opportunities to develop therapeutic strategies.

Our lab embraces and promotes diversity, equity and inclusion. We base our strengths on teamwork and believe that the most efficient way to achieve goals is through the collective search and discussion of ideas and approaches.


Neuroscience sensory and circadian biology; environmentally-induced disorders

Research Areas



Daily changes in light influence mood via inhibitory networks within the thalamic perihabenular nucleus. Weil, T; Daly, KM; Castillo, HY; Thomsen, MB; Wang, H; Mercau, ME; Hattar, S; Tejeda, H; Fernandez, DC. Science Advances. 2022; 8:eabn3567.

Light Has Diverse Spatiotemporal Molecular Changes in the Mouse Suprachiasmatic Nucleus. Duy, PQ; Komal, R; Richardson, ME S; Hahm, KS; Fernandez, DC; Hattar, S. Journal of Biological Rhythms. 2020; 35:576-587.

Retinal innervation tunes circuits that drive nonphotic entrainment to food. Fernandez, DC; Komal, R; Langel, J; Ma, J; Duy, PQ; Penzo, MA; Zhao, H; Hattar, S. Nature. 2020; 581:194-198.

Non-invasive Strategies for Chronic Manipulation of DREADD-controlled Neuronal Activity. Zhan, J; Komal, R; Keenan, WT; Hattar, S; Fernandez, DC. Jove-Journal of Visualized Experiments. 2019.