Educators educating Educators

Jul 21

Nobel Prize



“Learning is the means whereby we acquire new working knowledge about the world. Memory is the means whereby we retain that knowledge over time. Our abilities to learn and remember are essential to our sense of self and our ability to function effectively in daily life. Memory is the glue that holds our mental life together. As a result, we are who we are in large part because of what we have learned and what we remember from experience.

But what is memory? How does the brain capture and sustain it? Why does memory sometimes fail us? Those simple questions, of course, have exceedingly complex answers, and many biological details about the process of memory in humans and other animals remain unknown.”


Eric Kandel, Professor at Columbia University, Howard Hughes Medical Institute investigator, and winner of the 2000 Noble Prize in medicine



On the cellular level, how do we remember information?

Repeated activity, or practice, causes the synapses of the nerve cells to swell and make stronger connections. These changes are a form of cellular adaptation called synaptic plasticity. It is the process where new synapses are formed and old ones die.

Researchers have also shown that synaptic plasticity occurs more easily at certain times, such as in infancy, and more easily to particular parts of the brain during certain times. For instance, in adults it happens more easily in the hippocampus, which is the grand central station of learning.

Learning requires strengthening the affinity between neurons through a dynamic process called long-term potentiation (LTP). When the brain takes in new information, the demand causes activity between neurons.The more activity, the stronger the attraction becomes, and the easier it is for the signal to fire and make connections. This process is the fundamental principle of the retaining and retrieval of information, the neural process called learning.

The initial activity between two neurons causes the receiving neuron to reconfigure its receptors. If the firing continues, the neuron produces more building material for the synapse, and it is this strengthening of the infrastructure that allows the new information to develop as a memory.

Suppose you are learning a new vocabulary word. The first time you hear the word, circuits are created between two nerve cells. If you never practice the word again, the attraction between the two nerve cells naturally lessens, deteriorating the signal. You forget.

When I was in college in late 1960s, I was taught that the brain was immutable from birth, with a certain number of brain cells and fixed neuronal circuits. The only changes thought to occur were the lost of brain cells and a reduction of brain volume. But researchers have shown that experience and learning remodels the brain circuits. Examples of such neuronal plasticity include LTP, where memories and learning generate new circuits.

LTP begins with the initial perception of an experience generating the firing of a subset of neurons firing together. Synchronous firing makes the neurons involved more inclined to fire together again in the future, a tendency known as “potentiation,” which recreates the original experience. If the same neurons fore together often, they eventually become permanently sensitized to each other, so that if one fires, the others do so as well. This is known as LTP.

The hippocampus is embedded deep in the temporal lobe. As explained by Rita Carter in her new book The Human Brain, “experiences ‘flow through it’ constantly, and more of them are encoded in memory through LTP. Thereafter, the hippocampus is involved in retrieving most types of memories. When you recall an episode from your life, the hippocampus and the area around it are activated. During memory recall, the hippocampus is busy pulling together various facets of the memory from widely distributed areas of the brain.”

Eric Kandel, Columbia University College of Physicians and Surgeons, shared the 2000 Nobel Prize for Medicine by confirming this process of cellular change. He demonstrated that repeated activity and practice causes the synapses to swell and make new connections. Kandel showed that when people learn something, the wiring of the brain changes. He demonstrated that even acquiring simple pieces of information involves the physical alteration of the structure of the neurons participating in the process. As explained by Medina, “these physical changes result in the functional organization and reorganization of the brain. This is astonishing. The brain is constantly learning things, so the brain is constantly rewiring itself.”

Kandel Nobel Prize

Watch a 2:08 minute video as Eric Kandel discuss IN Search of Memory.



In case you get bored with the lazy days of summer and want to get a jump preparing for the coming school year, I added to Stuff4Educators a section called How to Study Better based on research from Harvard Medical School that highlights four science-backed ways towards better learning (Hint: drop the highlighter). Additionally, I posted a YouTube video under exercise from the Dana Foundation that won the Northwest Emmy award called Exercise and the Brain that explores the benefits of exercise on the brain and learning. Finally, some books that I have read this past year and found to be stimulating are listed.