Navigation Links
Learning causes structural changes in affected neurons
Date:2/3/2011

When a laboratory rat learns how to reach for and grab a food pellet a pretty complex and unnatural act for a rodent the acquired knowledge significantly alters the structure of the specific brain cells involved, which sprout a whopping 22 percent more dendritic spines connecting them to other motor neurons.

The finding, published in the journal Proceedings of the National Academy of Sciences by Mark H. Tuszynski, MD, PhD, professor of neurosciences and colleagues at the University of California, San Diego School of Medicine, underscores the brain's remarkable ability to physically change as it learns (not just in rats, but presumably in humans too), but also reveals that the effect is surprisingly restricted to the network of neurons actually involved in the learning.

"I think it's fair to say that in the past it was generally believed that a whole cortical region would change when learning occurred in that region, that a large group of neurons would show a fairly modest change in overall structure," said Tuszynski, who is also director of the Center for Neural Repair at the UC San Diego and a neurologist at the Veterans Affairs San Diego Health System.

"Our findings show that this is not the case. Instead, a very small number of neurons specifically activated by learning show an expansion of structure that's both surprisingly extensive there's a dramatic increase in the size and complexity of the affected neurons and yet highly restricted to a small subset of cells. And all of this structural plasticity is occurring in the context of normal learning, which highlights just how changeable the adult brain is as a part of its normal biology."

Tuszynski said the new work improves science's basic understanding of how the brain learns. "This tells us that learning may be mediated by relatively few cells, but that these few cells exhibit a substantial or extensive change in structure." Notably, the impacted cells in the rat study were not clustered together, but widely distributed over the motor cortex of the rat brain, suggesting that learned behaviors create expansive networks of distant cells.

Whether these new connections and changes are permanent is the subject of continuing research. For a rat, reaching for and grasping food is a learned behavior that takes time and repetition to master, not unlike a person learning to ride a bike or play the piano. If the behavior isn't regularly practiced, it becomes rusty, though it may be later resumed and remembered.

"This seems to be a 'hard-wired' form of memory," said Tuszynski. "We were curious whether we could find evidence of hard-wiring as part of learning in animal brains. We designed this study and our original hypothesis seems to be confirmed.

"Whether this physically represents the formation of long-term memory is hard to say" Tuszynski said, explaining that the data are correlative. "The rats learn, and we know that the learning is mediated by the small set of cells we studied. We know that adjacent cells in the cortex, which are not required to learn the new task, do not show the structural change. So presumably the structural change is occurring only in the learning neurons, and the learning would likely not occur without the structural change."

He added that in order to determine whether the structural change is necessary for the learning to occur, scientists would need to block the expansion in spines and then observe a failure to learn. "Yet the inference is quite strong that structural change is necessary for the learning to occur."

Tuszynski said it remains to be seen how the brain changes in other types of learning, such as language-based knowledge or arithmetic-type learning.

"Types of memory that require much repetition for learning and that don't fade away easily likely use this modification of (dendritic) structure to accomplish the learning," he said. "Other forms of memory that are not so hard to establish and which fade more rapidly may not involve such extensive structural changes. These are concepts that will be pursued in future studies."


'/>"/>

Contact: Scott LaFee
slafee@ucsd.edu
619-543-6163
University of California - San Diego
Source:Eurekalert  

Related medicine news :

1. Better learning through handwriting
2. Learning the language of bacteria
3. Nicotine exposure in pregnant rats puts offspring at risk for learning disabilities
4. U of M researchers find learning in the visual brain
5. Children with high blood pressure more likely to have learning disabilities
6. Sleep Appears to Aid Learning
7. Could learning self-control be enjoyable?
8. Clinical trials can be improved by managing the learning curve
9. Adiposity hormone, leptin, regulates food intake by influencing learning and memory
10. MIT researchers find that Sirtuin1 may boost memory and learning ability
11. Antioxidants may help prevent malaria complicaton that leads to learning impairment
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Learning causes structural changes in affected neurons
(Date:4/25/2017)... ... April 25, 2017 , ... ProRehab Physical Therapy ... the preferred physical therapy provider for Derby City CrossFit, effective immediately. , In ... as quickly and effectively as possible, ProRehab’s sports physical therapists will work with ...
(Date:4/25/2017)... ... , ... A stressful work environment can hurt the physical and emotional health ... in the workplace. The goal of Clearview Resolution Services has always been to help ... Resolution Services will be shutting down the office early on Fridays. The Clearview team ...
(Date:4/25/2017)... Boulder, CO (PRWEB) , ... April 25, 2017 ... ... Law and Liberty attempts to compare student test score performance for the 2015-16 ... one of the state’s voucher programs. Though it highlights important patterns in student ...
(Date:4/25/2017)... ... April 25, 2017 , ... Lake Park Dental is now accepting new ... in Lutz, FL. With the help of this highly-effective, yet convenient system, patients ... complications, more discretion and less pain. , Drs. Sarah Jockin, Nicole Morganti, Sara ...
(Date:4/25/2017)... ... 25, 2017 , ... As pharmaceutical companies are held to ... process innovation in drug formulation and manufacturing. CoreRx offers its clients more ... in support of their development and manufacturing goals. , The company was ...
Breaking Medicine News(10 mins):
(Date:4/20/2017)... 2017  AbbVie (NYSE: ABBV), a global biopharmaceutical ... chronic hepatitis C virus (HCV) infected patients with ... compensated cirrhosis (Child-Pugh A) achieved sustained virologic response ... its investigational, pan-genotypic regimen of glecaprevir/pibrentasvir (G/P). These ... 12 weeks of G/P treatment without ribavirin. Patients ...
(Date:4/19/2017)... Medical Corporation (TSX: CRH) (NYSE MKT: CRHM) (the "Company"), announces that it ... 2017 at the Sheraton Hotel in Toronto, Ontario ... the Company is scheduled to present on Tuesday, May 2 at ... Chairman of the Board, Tony Holler will also attend ... For more details ...
(Date:4/19/2017)... , April 19, 2017 Global Prostate ... report on the prostate cancer therapeutics market analyzes ... market. Increasing prevalence of prostate cancer, launch of ... the development of new drugs & therapeutic biological ... drug due to lesser side effects are some ...
Breaking Medicine Technology: