SYNAPTIC STRUCTURAL PLASTICITY: FROM MOLECULES TO COGNITIVE FUNCTIONS AND DISEASE Research in my lab centers on signal transduction networks that regulate the structural and functional plasticity of excitatory synapses. Synaptic communication between neurons within brain circuits underlies cognitive functions, and is disrupted in numerous neurodevelopmental and neuropsychiatric disorders. Most central excitatory synapses are located on dendritic spines, and spine structure is essential for normal and pathological brain function. Spine dynamics is crucial for the establishment, maintenance, and experience dependent modification of connectivity in neural circuits. Conversely, abnormal dendritic spine morphology occurs in patients with neurodegenerative, psychiatric, and neurodevelopmental disorders, including schizophrenia, autism, and Alzheimer’s disease. As spine morphology is closely associated with cognitive functions, understanding the mechanisms of regulation and dysregulation of spine plasticity is necessary to elucidate the neural bases of cognitive functions and disorders. The long-term goals of my research are: 1) to identify and characterize the molecular mechanisms that control synaptic structural plasticity. 2) to determine how they influence the development, functioning, and plasticity of brain circuits underlying cognition. 3) to uncover the molecular mechanisms underlying synaptic pathology and determine their impact on disease endophenotypes. To to achieve these objectives, we employ a multidisciplinary array of molecular, cellular, imaging, transgenic, electrophysiological, and behavioral approaches, and have assembled an outstanding team of collaborators.