Dr. Shai Sabbah Laboratory
News
Shai gives a talk at the European Retina Meeting
Shai gives a talk at the European Retina Meeting (ERM) in Helsinki about luminance encoding in the human brain.
Open Positions
We are currently recruiting highly motivated candidates for M.Sc. and Ph.D. studies
We study
neural circuits that underlie key visual functions in the retina and brain, including light adaptation and direction – and orientation-selectivity. We also study non-image-forming photoreception and the role of diverse brain pathways in mediating the effect of abnormal lighting on mood.
Our research
integrates an unparalleled array of cutting-edge techniques:
• Opto- and chemogenetics
• Functional imaging
• in vivo and in vitro electrophysiology
• Serial electron microscopy
• Behavioral analysis
Successful candidates will show solid communication skills in English, ability to work both independently and as part of a research team, strong scientific motivation, and skill in data processing. Experience in one or more of the following would be an advantage: intracranial surgeries, optogenetics, animal behavioral analysis, two-photon imaging, whole-cell and in vivo electrophysiology, and Matlab or python programing.
An application package, including a motivation letter, curriculum vitae, and names of 2-3 referees, should be sent to Dr. Shai Sabbah (shai.sabbah@mail.huji.ac.il).
What we think we do
We are interested in how animals and humans perceive the visual world and use this perceptual information to guide their behavior. Thus, by studying the structure and function of genetically distinct retinal and brain circuits, we seek to link the processing of brightness, contrast, color, and motion information to behavior.
We use mouse genetic models and combine:
- Reconstruction of neural circuits using light and electron microscopy
- in vitro and in vivo electrophysiology and functional imaging
- Optogenetic and chemogenetic manipulations of neural activity
- Behavioral analysis
For human research, we use functional magnetic resonance imaging (fMRI).
These powerful and complementary approaches allow us to reveal the operation of specific neural circuits and their role in shaping the behavior of animals and humans in unprecedented detail.
Luminance encoding in the human brain
The main pathway through which visual signals are routed to cortex includes the dorsal lateral geniculate nucleus and primary visual cortex. However, recent work has identified in the mouse a new separate pathway. This pathway includes the dorso-thalamic perihabenula and the ventromedial prefrontal cortex which plays a key role in mood regulation. In addition to […]
Retinal orientation selectivity
Orientation selective neurons, which respond to edges presented at certain orientations, have been documented in the retina and cortex. However, it is unknown whether cortical orientation selectivity is created de novo in the cortex, or instead derived from processing and integration of orientation-selective signals arriving from the retina, presumably through thalamic and collicular relay neurons. […]
Direction selectivity in the retina and brain
Visual motion tells us how objects are moving in the world, and how we are moving within that world. Our work has recently transformed the understanding of this system’s architecture in the context of the whole animal. We studied how the global geometry of retinal direction selectivity relates to optic flow induced by self-motion. By […]
Brain circuits that mediate the effects of light on mood
Light has a critical impact on mood disorders in ways we are only beginning to recognize, with the potential for the development of effective, relatively non-invasive therapies. However, until now, surprisingly little has been reported on the mechanisms underlying the effects of light on mood. We characterize a newly discovered pathway that links specialized retinal […]
Luminance-dependent modulation of retinal function
The mammalian retina maintains high sensitivity over an extraordinary range of luminance levels, ranging from starlight to bright sunlight. This is achieved by switching between the rod and cone systems, and within each system, by employing light adaptation mechanisms that preserve a contrast-invariant response. While dopamine is known to modulate retinal network activity in proportion […]