Cortical Mapping and Functional Connectivity
The development of visual perception comes from the complex interaction between neurons of different cortical areas and from the topography of the connections between cortical areas and within these areas.
In this context, the lab explores the relationship between visual perception and functional connectivity and cortical mapping in visual areas and beyond.
This research, carried out in mice performing visual discrimination behavioral tasks, involves the use of optogenetics to reversibly stimulate or inactivate different regions of the cortex.
This research also involves the use of functional imaging using calcium indicators such as GCaMP6.
In particular, they use spontaneous activity-based mapping approaches to explore functional connections through correlation approaches: Resting state mapping
Figure: Vanni et al. 2017 Journal of Neuroscience
Technological Development
Exploring functional mapping and connectivity involves the use of sensitive, specific, and resolving experimental approaches that only neurophotonics can provide.
The laboratory is also very involved in the development of these new experimental approaches in collaboration with the École Polytechnique and the startup LabeoTech: https://www.labeotech.com/.
Various projects, for example, are in progress on the development of projects and approaches allowing the simultaneous disruption and reading of the activity of neural circuits at the scale of the whole brain.
Other projects focus on the development of fully automated data collection systems.
Figure: Lim et al. 2013 Frontiers in Neuroscience
Strokes and Cortical Blindness
Although the vast majority of visual impairments are caused by ocular pathologies, a number, called cortical blindness, follow damage to the visual regions of the brain.
The development of a reliable animal model of cortical blindness will make it possible to evaluate new innovative therapeutic strategies such as those using non-invasive brain stimulation.
Figure: Balbi et al. 2017 JCBFM
Neuroprosthesis
To restore visual perception during the total loss of ocular functions, one of the strategies would consist in stimulating the cortex by taking into account the underlying cortical maps as well as the inhibition/excitation balance of the cortical networks thanks to optogenetics.
The strategy used will use computer vision to segment the visual stimuli by artificial intelligence and generate the cortical activation/inactivation sequence on the visual cortex of blind animals.
Cortical photostimulation would then be carried out using flexible OLED matrices in contact with the cortex expressing virally excitatory or inhibitory photosensitive proteins.
Figure: Balbi et al. 2017 JCBFM