Navigation Links
Area deep within the brain found to play role in sensory perception
Date:9/23/2007

The ventrolateral nucleus (VL) of the thalamus is connected to the cerebellum and motor cortex and therefore thought to be involved in motor function. A new study to be published in Annals of Neurology, the official journal of the American Neurological Association, found that the VL also plays a role in sensory processing and that damage to this area leads to functional and neural changes. The journal is available online via Wiley InterScience at http://www.interscience.wiley.com/journal/ana.

Investigations of the human VL have been limited to date, due to a lack of tools available to examine its function and the fact that lesions that occur in this region tend to be larger and therefore affect more than one nucleus of the thalamus. Thalamic nuclei are dense clumps of nerve cells found where the fibers from sensory systems terminate in the thalamus. Led by Tony Ro, of Rice University in Houston, TX, researchers conducted a series of behavioral and neuroimaging studies on a patient who had suffered a stroke affecting only the right VL, a rare occurrence. She had reported changes to her sensory abilities, such as bumping into the left sides of doorways or veering right when driving as a result of decreased sensations on the affected (left) side, but was otherwise normal. The patient was tested using visual and tactile stimuli and also underwent diffusion tensor imaging (DTI) scans, an imaging method that uses a magnetic resonance imaging (MRI) scanner to visualize the neuron fibers and connectivity in the brain. Experiments were conducted one, three and six years following the patients stroke.

In the years following her stroke, the patient experienced a dramatic change in her sensory perception: when she heard certain sounds, she felt tingling and other sensations in the left side of her body, especially her left arm. The results suggest that the VL lesion resulted in a significant amount of functional and neural reorganization that influenced sensory perception. For the first year and a half after her stroke, the patient demonstrated what is termed anti-extinction, in which she detected sensations significantly more on the impacted side when she was also stimulated on the unaffected side. The authors speculate that this may have reflected the initial stages of reorganization taking place in her brain. At that time, she also developed tactile sensations induced by sound, (sound-touch synesthesia), which may have been due to even further weakened pathways between the thalamus and cortex, a finding which was also suggested by the DTI results. The synesthesia persisted, and was still present six years following her stroke. Regardless of the exact neural mechanisms, this phenomenon of brain-damage induced feelings of sound suggests that other forms of synesthesia, in which reportedly neurologically normal individuals feel, taste or see something qualitatively different than the actual sensory input, may be due to cross-wiring in the brain, especially subcortically, the authors suggest. The results support previous studies suggesting that acquired forms of synesthesia may appear after months or years following brain damage.

The authors note that in addition to demonstrating a previously unknown role for the VL in sensory processing, the results suggest that connections between the thalamus and other brain areas may be important for the ability of the nervous system to change in terms of sensory processing following brain damage. Our results suggest that local disruption of the thalamus causes large-scaled changes in remotely connected regions of the brain, perhaps including excitatory connections between auditory and somatosensory cortex leading to the patients synesthesia, they state.

They add that the synesthesia may also have been caused by altered connections within the thalamus that help the processing of sensory information from the body to the brain when normal processing is impaired. The authors conclude that this case study provides tremendous insight into the consequences of VL thalamic brain damage and in the future plan to use other behavioral and neuroimaging methods to shed light on this phenomenon.


'/>"/>

Contact: Amy Molnar
amolnar@wiley.com
John Wiley & Sons, Inc.
Source:Eurekalert

Related medicine news :

1. Alcohol within the body
2. Resistant tumors could be treated with the discovery of a new molecule within cancer cells
3. World SARS-free within weeks
4. Molecular Computer Developed To perform Calculations From Within Human Body
5. Foot and Mouth Disease within Control
6. Innovative Movies Show Real-Time Immune-Cell Activity within Tumors
7. Mental Health Risks Vary Within the U.S. Black Population
8. Ancient Worm Disease Could Be Eradicated Within Two Years, UN Agency Reports
9. HIV/AIDS- Possible Cure From Within
10. Simple Test to Predict People Who may Develop Dementia Within Six Years
11. New Device Developed to Eliminate Superbugs Within Minutes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/2/2016)... (PRWEB) , ... December 02, 2016 , ... For over twenty-four years, Doctors on ... to help personal injury victims find high quality medical care. When the company started ... area. Fast forward to present day and the now ten-page directory features a vast ...
(Date:12/2/2016)... ... December 02, 2016 , ... Center for Autism and Related Disorders (CARD) Portland ... autism spectrum disorder (ASD) and other developmental disabilities. The group, which is being launched ... other caregivers the opportunity to share stories and advice, seek help, and continue their ...
(Date:12/2/2016)... (PRWEB) , ... December 02, 2016 , ... ... inspirational interview of two ostomy patients, standing as living proof that attitude and ... from digestive diseases and issues that spike around the holidays. This campaign will ...
(Date:12/2/2016)... Delaware (PRWEB) , ... December 02, 2016 , ... ... released a new version of its SaaS LIMS, CloudLIMS Lite. CloudLIMS Lite helps ... sample entry through labeling, storing, shipping and disposal. The new version is a ...
(Date:12/2/2016)... ... December 02, 2016 , ... Rijuven Corp launches rejiva ( http://www.rejiva.com ... and night. No other wearable health technology on the market can deliver all that ... poeple more meaningful insights about their health than the usual heart rate and steps ...
Breaking Medicine News(10 mins):
(Date:12/2/2016)... Dec. 2, 2016  The Addiction Treatment Advisory ... of Managed Care Pharmacy (AMCP), has released detailed ... address the opioid addiction crisis, including through improved ... ATAG,s newly released paper, "The Role ... Naloxone," addresses many issues around gaps and barriers ...
(Date:12/2/2016)...  Maxor National Pharmacy Services, LLC ("Maxor"), today announced that ... The combination of Texas -based Maxor Specialty ... bring together both company,s clinical expertise and high-touch patient service ... specialty pharmacy. About Maxor ... , , ...
(Date:12/2/2016)... -- CVS Health Corporation (NYSE: CVS ) ... December 15, 2016, beginning at 8:00 a.m. (ET). Senior members ... in-depth review of the company,s strategies to drive long-term ... discuss 2017 earnings guidance during the event. ... be broadcast simultaneously on the Investor Relations portion of ...
Breaking Medicine Technology: