Brain signals from the paralyzed or injured captured b...( stretch while other sensors in the ski...),Health

stretch, while other sensors in the skin respond to stretch and pressure. When an individual is paralyzed by injury or disease, neural signals from these sensors cannot reach the brain, and thus cannot be used to control motor responses. Paralysis also keeps neural signals originating in the motor regions of the brain from reaching the muscles.

The work of Weber and his colleagues shows that it is possible to extract feedback information from the body's natural sensors that could then be used to control a prosthetic device, allowing an individual to regain some command and control of his or her own movements.

A sterile surgical procedure is used to implant arrays of 36 microelectrodes into the dorsal root ganglion, part of the spinal nerve that contains the nerve cell bodies that house these natural sensors. Historically, it was difficult to record from these sensors because their cell bodies are located in this difficult-to-reach nerve bundle entering the spinal cord.

The wires from the microelectrode array are led out through the skin to a small electrical conductor. The procedure allows simultaneous recordings from many sensory nerves during normal motor activities such as walking. A digital camera tracks the position of the leg, and a mathematical analysis relates the sensory activity to leg movement. The investigators found that fewer than 10 neurons are needed to accurately predict the path of the leg. This finding is encouraging because it suggests that a small number of neurons could provide the feedback signals needed to control a prosthetic device.

Other investigators are developing wireless devices for recording neural activity. Groups from Brown University in Providence, R.I., and the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., have both developed wireless implantable devices that use advanced microelectronic technology that eliminates the shortfalls of currently available neural recording systems.

Accor
'"/>

Contact: Dawn McCoy
dawn@sfn.org
202-462-6688
Society for Neuroscience
10-Nov-2003

Page: 1 2 3 4 5
Related medicine news :

1. Brain activity prior to treatment flags vulnerability to antidepressant side effects
2. Brain imaging study may hold clues to onset of schizophrenia in people at high risk
3. Brain imaging reveals secrets of love, fear and betrayal
4. Brain imaging studies investigate pain reduction by hypnosis
5. Brain tumor with dismal prognosis in infants can be cured in older children
6. Brain-scanning technologies need standards, according to Stanford researcher
7. Brain activity of men and women during hostile or impulsive acts differs less on nicotine
8. Brain synapse formation linked to proteins, Stanford study finds
9. Brain tumor treatment can vary greatly, according to new JAMA study
10. Brain region identified that controls collecting behavior
11. Brain imaging reveals new language circuits