BMI SEMINAR // Guillermina Lopez-Bendito - Thalamic spontaneous activity in cortical sensory maps development and plasticity

During decades, it has been observed in humans and animal models that the brain has an extraordinary capability for adaptation after sensory loss. For example, it is well known that congenitally blind humans have a smaller visual cortex and expanded spared cortical areas, such as the somatosensory tactile. The mechanisms behind these observations were unknown. By the combination of calcium imaging, cellular and molecular biology and mouse genetics, this study demonstrates the existence of spontaneous waves of calcium activity that communicate in the thalamus distinct sensory systems, visual, auditory and somatosensory. These waves of information of neural activity maintain sensory systems in homeostasis and allow a normal development of sensory cortical areas. However, after a peripheral sensory loss, these waves of calcium activity in the thalamus are modified triggering gene expression changes and ultimately changes in cortical areas size all of which occurs in an experience-independent fashion. I will also recapitulate our recent findings demonstrating the role of these embryonic thalamic waves in controlling the development of cortical sensory maps.