Eric Kandel

Eric Richard Kandel was born in Vienna in 1929 and became one of the most influential neuroscientists of his generation. Trained as a physician and specialised in psychiatry, he devoted much of his career to a question that had preoccupied philosophers for centuries: how memory is stored. His work bridges the psychology of learning and the biology of the individual nerve cell, which is why it matters both to the history of ideas about the mind and to modern neuroscience.

His family was Jewish, and they were living in Vienna when Austria was annexed by Nazi Germany in 1938. Soon afterwards they left for the United States, and in 1939 the young Kandel settled in Brooklyn. At Harvard he studied History and Literature, writing a thesis on how three German writers had responded to National Socialism. There, under the influence of a fellow student whose parents were psychoanalysts, he became drawn to the biology of motivation and to the conscious and unconscious workings of memory. He earned his medical degree at New York University and went on to train in neurophysiology and psychiatry. He later directed the Center for Neurobiology at Columbia University.

The core of his research lies in studying learning in a simple animal, the sea slug Aplysia, whose nerve cells are accessible enough to record the activity of individual synapses. Kandel identified three basic forms of implicit learning: habituation, in which a repeated harmless stimulus gradually stops provoking a response; sensitisation, in which a harmful stimulus makes the animal react more strongly to everything; and classical conditioning, in which a neutral stimulus paired with a harmful one comes to trigger the same response. His experiments showed that these forms of learning change the strength of specific connections between neurons, and that short-term memory depends on how long those changes last. When repetition turns a temporary change into a lasting one, memory moves into the long-term stage. In this picture, neural plasticity, the persistence of a change after its cause has gone, becomes the cellular basis of memory. His findings also speak to the old debate between empiricists and rationalists: the layout of the circuit resembles something innate, while the strength of its connections reflects experience.

Kandel shared the 2000 Nobel Prize in Physiology or Medicine with Arvid Carlsson and Paul Greengard. His influence reaches beyond the laboratory. His more popular book In Search of Memory won the Los Angeles Times Book Prize for Science and Technology in 2006, and his work helped forge a firm link between psychology, psychiatry and the biology of the mind.