Popular Science (March 2013) reports that neuroscience has found technologies that may soon provide cures for dementia, seizures, paralysis, blindness and deafness by acting directly on the brain.
Researchers at the University of Pittsburgh have seen a 69 percent reduction in seizures over a five-year period.
Basically, seizures are stopped with an electrical jolt.
A seizure is caused by neurons that become overly excited. They issue a characteristic signature.
An electrode set on the scalp detects the signature and inserts an electrode array into the brain (an array is a miniscule device made of solid-state transmitter/receivers that acts as a kind of radar). The array emits its own electrical pulse, disrupting the over-exuberant neurons. The pulse passes through a polymer coating on the array that neutralizes the positive current. This is done to allow negatively charged anti-seizure drug molecules to drip from the electrodes and cause the positively charged neurons to calm down.
The body has a barrier protecting the brain and resistant to all but the smallest molecules, rendering most drug treatments ineffective. But the electrodes can carry minute amounts of drugs like dopamine or painkillers directly to the afflicted areas.
The arrays can be used not only for treatments of seizures but also for Parkinson’s disease, chronic pain and even drug addiction.
Dementia is an aberration that damages fundamental cognitive functions such as memory, decision-making, language and logical reasoning.
When we are paying attention or making decisions, neural signals travel back and forth between the second, third and fifth layers of the prefrontal cortex (the front of the frontal lobe, the foremost of the five lobes in each cerebral hemisphere).
An electrode array is implanted in the cortex to record the trips between the layers. Neuroscientists can analyze the neural signals slipping from layers 2/3 to 5 during the operation of the attention or decision functions and find out when they make the trips. Then the electrode array shoots out the same neural signal before it would have been have been fired naturally. Monkeys subject to testing procedures measurably improved their attention and decision-making abilities (comparing cartoon objects to the same images sent 90 seconds earlier). Even when the monkey’s thinking was impaired by a hit of cocaine, the electrical stimulation restored the accuracy of their cognitions.
Dementia appears in more areas of the brain than in layers of the prefrontal cortex, but increased understanding of dementia may allow scientists to insert the electrode arrays into other identified areas of the brain.
Other afflictions have been counteracted by activities conducted directly on the brain.
Eyesight is lost when disease injures photoreceptor cells (rods and cones) in the retinas. Rods and cones translate light into electrical signals that the brain can transmute into images.
Ganglion cells in the retina transmit the electrical signals to the optic nerve in the brain’s visual cortex (located in the occipital lobe on the other side of the brain from the prefrontal cortex).
A protein in the ganglion cells stimulates the firing of the signals. But ganglion cells aren’t working when a person is blind. How the treatment would work is that benign viruses would sails over to the retina and inserts genes into ganglion cells so that they can relay signals from the rods and cones to the visual cortex. The ganglion cells are inspired to “express” (force out) the protein into their membranes. The protein is what incites the cells to fire their neurosignals.
The procedure for administering the gene-carrying viruses will take only a few minutes and required only local anesthesia. The visual signals from the ganglion cells will be different than the brain is used to, but the brain is adept at making adjustments.
Paralysis involves the way messages pass between the brain and muscles. It can be complete or partial. It can occur on one or both sides of the body, in specific areas or be widespread. Paralysis in the lower half of the body and the legs is paraplegia. Paralysis of both the arms and the legs is quadriplegia.
The neurophysical treatment involves placing electrode arrays in the motor cortex and the somatosensory cortex. The motor cortex is located in the rear portion of the frontal lobe and does the planning, control, and execution of voluntary movements. The somatosensory cortex is located behind the central latitudinal fissure of the brain and receives impulses of the skin and subdermal structures. It then processes them into sensations of touch and taste.
Meanwhile, a microprocessor is mounted on the patient’s skull. When the patient begins to think about moving, the motor cortex issues neural commands that are picked up by the array and sent to the microprocessers, which pass them on to the exoskeleton. The exoskeleton is an external skeleton that supports and protects the body, in contrast to the internal skeleton, or endoskeleton. A primitive form of exoskeleton was metal armor. In this case it refers to a brace. The exoskeleton has a microprocessor too, which signals the leg to move. When the foot touches the ground, pressure sensors that have been lodged on the surface of the exoskeleton generate a tactile signal that heads back to the electrode array in the cortex. This creates a feedback loop between the exoskeleton and brain so that the patient can feel the ground as she moves her leg.
Through the financial support of the organization called the Walk Again Project, located in Brazil, where this research is being undertaken, a paraplegic man will deliver the opening kick at the 2014 World Cup in Sāo Paulo.
Ninety percent of people with hearing loss are helped by an electronic implant in the cochlea that acts as a kind of microphone to receive and transmit sounds. The cochlea, also called the inner ear, is shaped like a snail-shell, responds to pressure and sends electrical impulses along the auditory nerve to the brain.
But ten percent of the hearing impaired population has a loss caused by damage to the auditory nerve, which does not respond to a cochlear implant. The nerve cells, however, can be restored by embryonic stem cells.
Stem cells are exposed to growth factors (substances that cause the cells to differentiate into precursors of auditory neurons). The auditory cells derived from the stem cells are injected into the spiral ganglion at the base of the cochlea. The cells grow and reinforce the ravaged auditory nerves and connect with cells in the brain stem. The brain stem coordinates motor control signals sent from the brain to the body.
The process has so far been used on gerbils, whose range of hearing is similar to that of human beings. The gerbils selected for the experiment have damaged auditory nerves. By application of the treatment, the gerbils’ hearing has improved by about 46 percent.
Unfortunately, it may take years before the technique is tried out on humans. The benefits can extend beyond the restoration of auditory nerves, but can be applied to widespread hearing impairments to the level at which the patient can receive a cochlear implant.
Another obstacle to this treatment, of course, is the utilization of embryonic stem cells.
By use of the combined advancements in technology, brain science and medicine, we may soon have cures for dementia, seizures, paralysis, blindness, deafness, and other maladies.
Only time is needed.
By: Tom Ukinski