Nonconcussion head impacts in contact sports linked to brain changes and lower test scores

Nonconcussion head impacts in contact sports linked to brain changes and lower test scores

Using a form of magnetic resonance imaging, or MRI, researchers at the Indiana University School of Medicine and the Geisel School of Medicine at Dartmouth College found significant differences in brain white matter of varsity football and hockey players compared with a group of noncontact-sport athletes following one season of competition. White matter is composed primarily of axons, the long fibers that transmit signals between neurons.

"The contact sports and noncontact-sports groups differed, and the number of times the contact sports participants were hit, and the magnitude of the hits they sustained, were correlated with changes in the white matter measures," said Thomas W. McAllister, M.D., chair of the IU Department of Psychiatry.

"In addition, there was a group of contact sports athletes who didn't do as well as predicted on tests of learning and memory at the end of the season, and we found that the amount of change in the white matter measures was greater in this group," Dr. McAllister said.

The study was conducted while Dr. McAllister was Millennium Professor of Psychiatry at Dartmouth.

"This study raises the question of whether we should look not only at concussions but also the number of times athletes receive blows to the head and the magnitude of those blows, whether or not they are diagnosed with a concussion," Dr. McAllister said.

Two groups of Dartmouth athletes were studied: 80 football and ice hockey players in the contact sports group, and 79 athletes drawn from such noncontact sports as track, crew and Nordic skiing. The football and hockey players wore helmets equipped with accelerometers, which enabled the researchers to compile the number and severity of impacts to their heads. Players who sustained a concussion during the season were not included in the analysis.

The athletes were administered a form of MRI test known as diffusion tensor imaging, which is used to measure the integrity of the white matter. They were also given the California Verbal Learning Test II, a measure of verbal learning and memory.

The study did not find "large-scale, systematic differences" in the brain scan measures at the end of the season, which the authors found "somewhat reassuring" and consistent with the fact that thousands of individuals have played contact sports for many years without developing progressive neurodegenerative disorders.

However, the results do suggest that some athletes may be more susceptible to repeated head impacts that do not involve concussions, although much more research would be necessary to determine how to identify those athletes.

More work would also be necessary to determine whether the effects of the head impacts are long-lasting or permanent, and whether they are cumulative.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.

SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc

we are focus on the following fields,and hope we can help you.

Fairchild Semiconductor Transistors Resistors Infineon Technologies Transistors AVX Resistors chip Filter saws ON Diodes Schottky Diodes Electronic News Military IC TI IC ELPIDA IC Resistor Arrays Diodes IDT IC NXP Transistors Zener Diodes Fleld Effect Transistors ROHM Resistors IC(Integrated Circuits) Capacitor Voltage Regulators Transistors Vishay resistors About US Rectifier Diodes BB IC TOSHIBA Diodes YAGEO Resistors components Fast Recovery Diodes Diodes Inc Kingbrigt LED Thick Film Resistors Renesas parts IC PANASONIC Resistors Chip Ferrite Beads Chip Inductors INTERSIL IC Switching Diodes Freescale Semiconductor Other Parts
http://www.suvsystem.com/a/8006.aspx