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Show The Daily Utah Chronicle, Thursday. November 18, 1976 Page Five Researchers work on computer eye TORONTO. ONT. Ardicial eye researchers at the University are working on a wearable, knapsack-size- d bMr.d ersrii w" computer nd crtnrr to detect people and objects by sending signals to electrodes placed on his brain. The research team plans to complete and begin testng the system in two years. For the past 14 months a blind volunteer with electrodes permanently implanted in the visual center of his brain has been reading braille with the aid of a large laboratory computer system. "Ye know now that we can transfer useful information through this system," says Michael G. Mladejovsky, director of the Neuroprostheses Program in the University Institute of Biomedical Engineering. "Now we are beginning to work on shrinking the whole assembly to a size that will allow experiments in mobility. We want to see how it can help a blind person interact with his environment by finding doors, steps and objects and avoiding other people " Far in the future the researchers hope the TV camera can be miniaturized and placed in a glass eye with wires connecting it to electrodes implanted in the visual cortex. Mladejovsky and Jerald R. Evans, a doctoral student in computer science, are in Toronto this week to present reports on the artificial vision project at the annual meeting of the Society of Neuroscience. They are among a dozen University scientists in fields ranging from bioengineering and computer science to anatomy and neurology participating in the meeting. The artificial vision project began in 1970 when the team began traveling around the US. and Canada performing brief electrode stimulation experiments on sighted volunteers who were undergoing brain surgery for other reasons. The purpose was to confirm 1968 British findings that electrical stimulation of the visual cortex in the back of the brain caused people to perceive dots of light or phosphenes. The research team received international notice in January 1974 when it reported that two healthy blind volunteers had been able not only to detect phosphenes but to identify letters of the alphabet through stimulation of electrodes temporarily implanted in their brains. In these experiments wires were left protruding from the patients' Professor studies The first anticancer drug-nitro- gen mustard was scalps during the tests and the entre electrode arrays were removed after three to eight days. During the summer of 1975 the program advanced with the development of a technique lcr permanent electrode implantation. Instead of coming through the scalp direct!, the wires from the electrodes terminate in a connector that is enclosed inside a special graphite material This connector object in the scalp housing is visible as a button-shape- d behind the ear. "Our progress has increased exponentially in the past year because the permanent implant gives us the experiments," opportunity to plan continuing, long-terMladejovsky says. man who had been blinded by a Craig, a decade has been wearing such a chronic a before, gunshot for 14 months. Through stimulation of his implant been able to read braille has Craig array, sentences transmitted to him by computer and identify horizontal and vertical lines scanned by a TV camera. "Over the past year we have made a detailed investigation of the parameters we need to understand in order to design a permanent visual prosthesis," Mladejovsky says. "We need to know such things as exactly how much current is necessary to produce a desired effect and whether this changes over time. "One result we have found that bodes well for the future is that the amount of electric current required to produce a particular phosphene sensation does not increase with time. This indicates that the electrodes are probably not damaging the surrounding brain tissue and body fluids are not affecting the electrodes. "Another finding is that the volunteer receives basically the same perception from a single stronger pulse of electric current that he receives from a rapid series of weaker pulses. The potential here is that the use of single pulses may allow faster transmission of information particularly from a moving scene." Evans will report to the meeting on data collected during the last eight months on the volunteer's own subjective descriptions of what he "sees." This includes data from each of the 64 electrodes on size, brightness, color, single or multiple appearance and compactness of the phosphenes produced at different levels m ld de to the patient and the side effects of these drugs are given to the first patient 34 often severe." "If we can gain a better years ago. Since then more than 1,000 scientific papers understanding of what is have been published on the involved in the subject but no one can yet process, maybe we can ways to protect explain how nitrogen design mustard and other antitumor normal cells while we kill the tumor cells." drugs actually kill cells. Most anticancer drugs And no one knows how to cells by inhibiting the from insult these killing drugs keep certain normal body cells sythesis of nucleic acids, RNA and DNA, which control along with the tumor cells. This is the problem being cell reproduction and the studied at the University manufacture of enzymes, he College of Pharmacy by Dr. says. But this insult does not Arthur M. Cohen, assistant directly kill the cell and its professor of biopharmaceuti-ca- l effect is limited to rapidly sciences. dividing cells such as the "Most anticancer drugs cells of tumors, bone marrow now in use don't have a very and the small intestine. "We are trying to wide safety margin," Cohen kill determine exactly how this says. "They normally to a insult level at cells a dosage tumor dividing cell sets in the which motion is that toxic below process which just cell-killin- g kills it" Cohen said. "For researchers at the clinical level, the fact that the insult results in the death of tumor cells makes the drug a useful one." "But we'd like to know enough about the killing process of the drug to limit its effects to tumor cells and protect other dividing cells in the body." "We know that if we treat an animal with nitrogen mustard at certain doses, the dividing cells of the small intestine will die within several hours. But if we pretreat with a drug called cycloheximide, the cells will not die. The nitrogen mustard will still stop replication of the cell, but somehow the response which causes the cell to die is blocked," said Cohen. Cycloheximide cannot be used clinically to prevent the side effects of anticancer drugs on the small intestine because it extremely toxic and it actually enhances the damage caused by nitrogen mustard to some other body cells, such as lymphoid cells. "The most promising course seems to be to find the exact killing mechanism m V"" y' drugs anti-canc- er - which nitrogen mustard sets in motion, them try to design ways to protect normal cells from that action," he adds. For the past two years Cohen has been working on a hypothesis that nitrogen mustard somehow sets in motion the activation of lysosomal enzymes which break down and destroy the cells. But he found that these enzymes apparently appear too late in the chain of events to be involved in the actual g process. They seem instead to be part of the body's cleaning-u- p process after the damage has been done. ( research is being supported by grants from the National Cancer Institute. A second area of research which Cohen is conducting with doctoral student Maria Pallavicina involves possible ways to increase the pj a ij rT l r5 r-- r5 J .J m CHICANO 1 p3 m m STUDENT ASSOC 1 Sub for Santa Chicano 1 Dinner 1 Thanksgiving $2.50 Donation 1 purchase tickets at Chicano Student Center J2I Vnion BUg. I 5SI-J04- 7 m Tuesday Nov. 23, 1976 00 a.m. 3:30 p m. 11 -- Newman Center 1 Poor Prize: 1327 - E. 200 S. m A TURKEY! TOMORROW EDWARD BRANDT J. Associate Director, Institute of Religion FRIDAY 11 NOON DEVOTIONAL Central Institute MM ( Ml M IK )( )l I M UK 01 November therapies for cancer by better si M MKM lN vIS In Chapel or combination drug scheduling. The two researchers are now studying the effects of drugs on the growth cycles of mammary rumors in mice through a sophisticated new NEED MONEY procedure called flow FOR cytometry. MEDICAL SCHOOL? r Air Force scholarships are available to S on students competitive basis. If you are qualified a for selected scholarship and subsequently accepted by an accredited school of medicine, the Air Force may elect to sponsor your four years of medical school under the Armed Forces Health Professions Scholarship Programs. If you have two years of college remaining, have a 3.50 GPA or higher, and will complete one full yeai of the below listed courses by the end of your junior year of school, then you may compete: two-yea- & SERVICE IS NOW LOCATED AT FOR AN APPOINTMENT ASK ABOUT OUR FREE SHUTTLE SERVICE TO AND FROM SCHOOL OR Arthur M. Cohen (right) Pallavincini Maria student inject mice and doctoral of the effect of a oi as study with an anticancer drug part tumors: of mammary drugs on the growth cycles performed by Dr. John P. Girvin of the Department of Clinical Neurological Sciences at the University of Western Ontario and Dr. Theodore S Roberts, a University oi Utah neurosurgeon. William H. Dobelle. former director of the Neuroprostheses Program who is now setting up a division of artificial organs at Columbia University, is a on the project effectiveness of single drugs 1333 EAST 33RD SO. PHONE 467-548- 9 TTnivoreitv r,hnrmnmlocrist Dr. he-rasphe- This FOREIGN & AMERICAN REPAIR W "One goal of our exper.ments is to devise an electrode array that is large enough and covers enough of the visual field with phosphenes to produce crude images of more complex cbects such as human faces," he adds. Mladejovsky says the team is now working on a larger electrode array and hopes eventually to use as many as 256 on each or side of the brain. The surgical implants for the research have been cell-killin- BICH'S SERVICE " of electrical current Drop Your Car Off At Our Other Shop Located at 302 So. 9th East pre-me- d pre-me- d English General Chemistry (including lab) Physics General Biology or Zoology Organic Chemistry (including lab) Mathematics through Analytical Geometry and Differential and Integral Calculus scholarships pay full tuition, books, fees, and S100 per month tax free. For more information without obligation Contact: Captain Dan Jones AFROTC Detachment 850. Annex 2009 U. of U. Phone 581-623- 6 Pre-me- d |