Memories in the making

To hear Tom Carew tell it, he’s barely worked a day in his life. For the last 30 years, the renowned scientist has been chipping away at one of life’s great mysteries: “Why do we remember some things for a few seconds and other things for a lifetime?” For this, he says, he gets paid to play.

“I don’t feel like I have a job, but I do have a strong goal to learn as much as I can,” he said. “I feel that we as academics are privileged to do what we do — making a living by using our minds.”

Carew, a Bren Professor and chair of UCI’s Department of Neurobiology and Behavior, did not start out to crack the code of learning. Growing up in Southern California, his aim was to keep surfing for as long as possible. But after earning his bachelor’s degree in psychology at Loyola University, Los Angeles, the study of brain and behavior lured him into the laboratory where he earned his master’s and doctoral degrees at California State University, Los Angeles and UC Riverside, respectively.

This was at a time when people in the field of learning and memory were creating experimental amnesia, Carew added. “It was a very exciting field for me, since it provided a window on memory processing in the brain. I was hooked.”

But for Carew, the real “eureka” came after he finished his Ph.D. in 1970.

“I realized that — having studied experimental amnesia in rats while recording from their cortex — I had a rich vocabulary about brain processes, but I really didn’t understand anything about actual mechanisms of memory. I turned to a simple invertebrate model for my post-doctoral studies and saw exciting connections. I felt that I could actually see memories in the making.”

That invertebrate model was a simple marine mollusk calledAplysia. Carew, who is now considered a pioneer in the cellular biology of learning, which combines psychology and neurobiology, began studying the sea slug’s nervous system.  Composed of 20,000 neurons — as compared to 100 billion neurons in the average human brain — the nervous system of the Aplysia lends itself to the study of biophysical and molecular changes, allowing scientists to observe how memories are encoded by tracking cellular changes that occur in specific nerve cells during memory formation.

Through innovative research at New York University and Columbia University in the 1970s and 1980s, Carew began piecing together the mystery of how memories are made. He observed how neurons change as information travels from one synapse to another, evolving from short-term memory to long-term memory. By now he was making his mark among neuroscientists. His key findings involved how these messages are related to different forms of learning at synaptic and molecular levels of analysis.

When he joined the faculty at Yale University in 1983, Carew already was a leader in the neurobiology of learning. He set about describing the relationships among the three basic forms of learning: habituation, sensitization and conditioning. He studied varying forms of neuroplasticity throughout the stages ofAplysia development and found that associative learning emerges last in development, as a product of habituation and sensitization, shedding new light on the foundations of associative learning.

Carew continued his research into mechanisms of memory while serving as the John M. Musser Professor of Psychology and chair of the Department of Psychology at Yale. He received the 1990 National Institute of Mental Health’s MERIT Award and was elected a member of the Society of Experimental Psychology. He received the 1990 Yale College Dylan Hixon Prize for Excellence in Teaching the Natural Sciences and is the author of two college-level textbooks and more than 140 articles published in leading journals. In September 2001 he was elected a fellow of the American Association for the Advancement of Science

Carew was drawn to UCI in 1999, he says, by its potential to make a mark in brain research. And for both Carew and his wife, Mary Jo, who teaches at Eastbluff Elementary School in Newport Beach, coming to UCI was like returning home. Both are native Californians.

“There is a feeling at UCI that the best is yet to come,” he says. “UCI is in an academic growth spurt and is on an exciting trajectory. It has first-rate scientists and a can-do attitude — which makes it a wonderful place to continue not having a job.”