The continuous acquisition, processing and consolidation of information are quintessential brain activities of fundamental importance to our everyday experiences and survival. Neuronal synapses play critical roles in these activities by functioning as information conduits to systematically wire the estimated 100 billion neurons into functional neuronal networks in our brain. Synaptic malfunction or failure causing abnormal alterations and/or destruction of neuronal networks are critical processes involved in neurodevelopmental and neurodegenerative disorders. Focusing on synapses and the neuronal networks they support, our research aims to identify mechanisms contributing to neuronal network formation and dysfunction. In doing so, we hope to unravel the biological principles that govern the emergence of brain function during development and its decline during aging and neurodegeneration.