Navigation Links
Adult brain can change, study confirms

CAMBRIDGE, MA (09/05/07)--It is well established that a child's brain has a remarkable capacity for change, but controversy continues about the extent to which such plasticity exists in the adult human primary sensory cortex. Now, neuroscientists from MIT and Johns Hopkins University have used converging evidence from brain imaging and behavioral studies to show that the adult visual cortex does indeed reorganize-and that the change affects visual perception. The study appears online Sept. 5 in an advance publication of the Journal of Neuroscience.

The authors believe that as scientists find ways to use this adaptive ability, the work could have relevance to topics ranging from learning to designing interventions for improving recovery following stroke, brain injury, or visual disorders.

Animal studies conducted two decades ago and using single cell recording of neurons found that the adult animal brain can change, but shed little information about the adult human brain. In 2005, a functional magnetic resonance imaging (fMRI) study led by Professor Nancy Kanwisher at the McGovern Institute for Brain Research at MIT found evidence of plasticity in the visual cortex of adults with macular degeneration, an eye disease that deprives regions of the cortex of visual information. But another fMRI study of macular degeneration found no such evidence, and an animal study using both single cell recordings and fMRI also questioned the 20-year-old animal work.

Lead author Daniel Dilks, a postdoctoral associate in Kanwisher's lab who conducted the current work while a graduate student at Johns Hopkins in senior author Michael McCloskey's lab, jumped into the fray when he found BL, a stroke patient. BL's stroke damaged the optic radiation fibers, which transmit information from the eye to the primary visual cortex, but the cortex itself remained intact. The damage eliminated input from the upper left visual field to the corresponding region of the primary visual cortex, thereby depriving a region of cortex and creating a blind area in the upper left visual field. The researchers want to find out what happened to that deprived piece of cortex. We discovered that it took on new functional properties, and BL sees differently as a consequence of that cortical reorganization, explains Dilks.

BL had reported that things looked distorted in the lower left visual field (below his blind area). The researchers hypothesized that the distortions resulted from cortical reorganization in the deprived cortex. To isolate that distortion, they had BL fixate on a center dot while objects, such as squares, appeared in various parts of the visual field. As expected, BL saw nothing when a square appeared in his blind area. But when the square appeared just below the blind area, he perceived the square as a rectangle extending upwards into the blind area. Likewise, he saw triangles as pencil-like, and circles as cigar-like.

Subsequent fMRI studies confirmed that the visually deprived cortex (representing the upper left visual field) was responding to information coming from the lower left visual field. The deprived cortex assumed new properties, a hallmark of plasticity, and that explained the visual distortions.


Contact: Elizabeth Thomson
Massachusetts Institute of Technology

Related biology news :

1. Recent breakthroughs in common adult leukemia highlighted in New England Journal of Medicine
2. Study finds adult stem cells can replicate
3. New Finding May Aid Adult Stem Cell Collection
4. Researchers discover mechanism for multiplying adult stem cells
5. Suppressing growth hormone in early adulthood may prevent cancer
6. A new window into structural plasticity in the adult visual cortex
7. MIT researcher finds neuron growth in adult brain
8. New neurons take baby steps in the adult brain
9. Neurons generated in the adult brain learn to respond to novel stimuli
10. Adult stem cells aid recovery in animal model of cerebral palsy
11. Changes to embryos can elicit change in adult fish
Post Your Comments:
(Date:6/22/2016)... , June 22, 2016 On Monday, the ... to industry to share solutions for the Biometric Exit ... Customs and Border Protection (CBP), explains that CBP intends ... departing the United States , in ... to defeat imposters. Logo - ...
(Date:6/20/2016)... Securus Technologies, a leading provider of ... safety, investigation, corrections and monitoring announced that after ... secured the final acceptance by all three (3) ... Systems (MAS) installed. Furthermore, Securus will have contracts ... by October, 2016. MAS distinguishes between legitimate wireless ...
(Date:6/15/2016)... , June 15, 2016 ... market report titled "Gesture Recognition Market by Application Market - Global ... 2016 - 2024". According to the report, the  global ... billion in 2015 and is estimated to grow ... 48.56 billion by 2024.  Increasing application ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... San Diego, CA (PRWEB) , ... June 27, 2016 , ... ... mClinical solutions for clinical trials, announced today the Clinical Reach Virtual Patient ... and their care circle with the physician and clinical trial team. , Using the ...
(Date:6/24/2016)... TOKYO , June 24, 2016  Regular discussions on ... to take place between the two entities said Poloz. ... in Ottawa , he pointed to the ... and the federal government. ... Poloz said, "Both institutions have common economic goals, why not ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... is pleased to announce the launch of their brand, UP4™ Probiotics, into Target ... over 35 years, is proud to add Target to its list of well-respected ...
(Date:6/23/2016)... Lawrence, MA (PRWEB) , ... June 23, 2016 ... ... the Peel Plate® YM (Yeast and Mold) microbial test has received AOAC Research ... test platform of microbial tests introduced last year,” stated Bob Salter, Vice President ...
Breaking Biology Technology: