Ancient rules of memory

Abstract

The first kiss, the smell of mother's cooking or the vision of a beautiful landscape; memories such as these are etched firmly into our brains for recall in vivid detail, even decades later. Memories and experience influence our decisions throughout life, both consciously and subconsciously—in a sense, our memories make us what we are. Yet, understanding how information is encoded in our brains and how memories are maintained, both at the conceptual and molecular levels, remains one of the greatest challenges in the life sciences. Through decades of research, biologists have answered many fundamental questions about the brain, and more recent work has revealed the identity of several crucial molecules involved in the storage and retrieval of information. This has at last begun to shed light on the major scientific puzzle: how do we form and maintain long‐term memories? ![][1] The field of neurobiology had made relatively little progress toward understanding memory since the Canadian psychologist Donald Hebb (1904–1985) introduced the idea of synaptic plasticity nearly 60 years ago (Hebb, 1949). Hebb explained the establishment of memory by changes in the number and strength of synaptic connections between neurons. According to his theory, synapses respond to stimulation by neurotransmitters in a cumulative manner, and repeated stimulation—for example, by learning—leads to ever‐stronger connections between specific neurons until they become permanent. Over time, neuroscientists accepted Hebb's idea of synaptic plasticity, despite a lack of direct molecular evidence. In fact, it was not until recently that scientists—in large part Eric Kandel at Columbia University in New York, NY, USA—discovered several biochemical mechanisms that now support Hebb's idea. Kandel himself won the Nobel Prize for medicine in 2000 for his discovery that the syntheses of different proteins relate to short‐term and long‐term memory in the sea slug Aplysia . The foundations for this work and … [1]: /embed/graphic-1.gif