The scientists, led by Wen-Biao Gan, PhD, associate professor of physiology and neuroscience at NYU School of Medicine, discovered that a delicate balancing act occurs in the brain where neuronal connections are continually being formed, eliminated, and maintained. This feat allows the brain to integrate new information without jeopardizing already established memories, the new study suggests.
Using a powerful optical imaging technique called two-photon microscopy, Dr. Gan and colleagues at The Helen and Martin Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, viewed the precise changes that take place at synapses, the junctions where nerve cells communicate, in the wake of learning a new task or being exposed to a novel situation. New knowledge, explains Dr. Gan, prompts alterations in the dendritic spines, the knobby protrusions along the branching ends of nerve cells. With learning, spines are gained and others lost.
“We’ve known for a long time that the brain remodels after learning,” says Dr. Gan “Our studies show that the brain does this in two ways: by adding a tiny fraction of new connections to the brain’s neural circuitry and eliminating old ones.”
Dr. Gan and his associates tracked changes in the brains of mice before and after experiencing a new stimulus (a string of beads hung at different places along the cage) or learning a new task (running on an accelerated spinning wheel). To open a window to the brain, the team shaved away the skull over the animals’ cortex in which the nerve dendrites were lit up by fluorescent proteins. Then, using a two-photon microscope, they snapped photos of the dendrites after the animals learned to stay on the running wheel or encountered the newly positioned beads. The team began photographing the mice when they were a month old and followed them through adulthood.
When the team compared the photos across the months, they observed new spines emerging in response to the beads’ placement or learning to run on the wheel. They saw, too, that as the mice became improved at spinning the wheel, a minute fraction of new spines continued to persist. The researchers also noted that at the same time as these new and lasting spines were created, a corresponding number of older spines that had been formed early in the animals’ development before the experiment began, disappeared.
Despite the rise and fall of dendritic spines, the animals’ brain circuitry remained overwhelmingly secure. A mouse neuron can carry ten thousand spines on its dendrites. Over months, about 100 spines were either gained or lost on each nerve cell after exposure to new experience while the majority of existing spines are maintained.
The study gives a clue as to how it is possible for humans, who have hundreds of thousands of spines on one neuron, to live each day, constantly experiencing and learning new things, without losing existing memories. “The brain is a dynamic and stable organ,” says Dr. Gan.
The authors of the new study are Dr. Gan and two postdoctoral fellows in his laboratory, Dr. Guang Yang and Dr. Feng Pan.
The study was supported by grants from the National Institutes of Health, a Dart Foundation Fellowship and an Ellison/AFAR Postdoctoral fellowship.About NYU Langone Medical Center
Dorie Klissas | Newswise Science News
Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology
Pan-European study on “Smart Engineering”
30.03.2017 | IPH - Institut für Integrierte Produktion Hannover gGmbH
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
30.03.2017 | Health and Medicine
30.03.2017 | Health and Medicine
30.03.2017 | Medical Engineering