Advanced Medical Scientist-Programm 2021

Thema: "How senses work together: Cross-modal integration and plasticity in the adult mouse visual cortex"

Zusammenfassung:
Animals and humans constantly receive inputs from different sensory modalities simultaneously. While previous studies assumed that multiple sensory inputs converge only in higher association areas of the brain, recent studies provide evidence for multimodal merging already at the level of primary sensory cortices. However, how cross-modal inputs in primary sensory cortices modulate sensory processing of the main sense, and how they plastically adapt after sensory loss remains unknown. Here, we will address these issues by investigating the cross-modal effects of whisker-based tactile sensation on visual processing in the primary visual cortex (Vl) of adult mice before and after vision loss. Notably, our preliminary data indicate that whisker stimulation cross-modally suppresses visually driven Vl activity. We will further examine how tactile inputs affect important attributes of vision such as visual acuity, contrast sensitivity and orientation tuning in Vl. For this, we will use cutting-edge techniques such as in vivo intrinsic and two-photon imaging. To unravel the underlying anatomic pathways, we will perform retrograde and anterograde trans-synaptic anatomical tracing. These data will be analyzed by a novel algorithm based on deep learning for 3D detection of tracer-labeled cells. Finally, we will examine plastic changes in this cross-modal interplay after vision loss (VL) in vivo using again intrinsic and two-photon imaging . We assume that VL will induce a cross-modal functional recruitment of Vl by whisker-based tactile inputs. Our study will extend our understanding about cross-modal integration and will provide mechanistic insights into cross-modal plasticity after sensory loss in adult mice