Dr. Sally A. Marik

The Rockefeller University


In her words:

In the cerebral cortex, millions of neurons integrate information from the five senses to create the organism’s perception of the world. Every neuron makes connections via their axons with thousands of other neurons across multiple locations within the cortex and throughout the brain. Mapping out exactly how these connections are maintained and altered in the adult is crucial to our understanding of the brain and its functions and dysfunctions, such as memory formation and
neurodegenerative diseases.

I visualize axons within the cortex by using a virus that delivers GFP, a green fluorescent protein that was first extracted from jellyfish. The labeled neurons and their axons can be observed with a two-photon microscope. Axons are visualized, recorded, and compared over time. Under normal conditions, axonal structure is stable, but new experiences (such as learning, trauma, or disease) alter the connections or the entire structure by creating completely new axons and removing already existing ones. This process of axon remodeling may be a key to learning and memory formation.