On the Science Front
Undated (AP) _ Here is a summary of scientific developments:
CHICAGO (AP) - An experimental technique for instilling unconscious memories in people suffering from a form of amnesia offers hope for teaching them complex new knowledge, a researcher says.
The technique was used to help an amnesiac woman learn enough about computers to get a job, said Daniel Schacter, assistant psychology professor at the University of Toronto.
Schacter and colleague Elizabeth Glisky taught the 32-year-old woman her new skill, transferring information from cards to a computer, by training what Schacter calls ″implicit memory.″
That is information that amnesics and normal people draw on unconciously, Schacter explained Sunday at the annual meeting of the American Association for the Advancement of Science.
Memory problems are usually defined as deficits in explicit memory, and ″even our most severely amnesic patients can perform fairly well on tests of implicit memory,″ Schacter said.
Schacter’s work focused on ″anterograde″ amnesia, in which the victim has difficulty recalling information presented since the onset of the illness.
The problem is frequent after severe head injuries, and ″many, many thousands″ of people have some degree of it following such injuries, encephalitis, ruptured blood vessels in the brain or other causes, Schacter said.
In the better-known form of the disease, ″retrograde″ amnesia, the sufferer has trouble recalling events before the disease.
CHICAGO (AP) - AIDS patients could be quarantined with electronic monitors used to confine parolees to their homes, says a manufacturer of the devices.
The devices could also be used to prevent brain-impaired people from becoming lost, David Hunter, president of BI Inc. of Boulder, Colo., said at the annual meeting of the American Association for the Advancement of Science.
At a symposium on new uses of technology against crime, Hunter said the monitors are in limited use now to tell law enforcement officials when inmates paroled on condition they stay home have strayed farther than allowed.
The monitoring system incorporates a small radio transmitter strapped to the ankle of the person being monitored, a radio receiver in the home, and a telephone link to a computer that will sound an alarm if the person being monitored leaves home.
The device does not physically restrain the person being monitored. It is designed to trigger an alarm if the wearer attempts to remove the transmitter from his or her ankle.
Hunter said using the device to quarantine acquired immune deficiency syndrome sufferers or victims of brain ailments such as Alzheimer’s disease could draw objections from civil liberties groups.
CHICAGO (AP) - A new technique called chromosome mapping could be the first step toward deciphering the human genetic code, a biologist says.
″We’re learning things already that we couldn’t have anticipated,″ Charles Cantor of Columbia University in New York said Monday at the annual meeting of the American Association for the Advancement of Science.
The mapping provides a rough guide to the location of various genes on the 23 pairs of human chromosomes, Cantor said.
″It looks thus far like the human genome (the full complement of genes) is a mosaic, sort of striped,″ Cantor said. ″It’s too early to know what this means, but we were very surprised to see any molecular pattern.″
Cantor speculated that the pattern, in which certain bands on the chromosomes are festooned with molecules called methyl groups and other bands are not, could indicate which genes are universally expressed in the body and which govern specialized functions in certain classes of cells.
The genes carrying the methyl groups may be the specialized genes and the genes without methyl groups may be more generally important, Cantor said.
The entire human genetic code, if it were written out, would fill 200 volumes each the size of the Manhattan telephone book, said Cantor.
Such a ″book of man″ could help researchers understand and perhaps develop new treatments for many genetic diseases, he said.
Chromosome mapping separates chromosomes, the fibrous structures that carry genes, into ordered fragments, each of which has a length of several hundred thousand nucleotides, Cantor said.
Nucleotides are the fundamental building blocks of genes. The entire human genetic code is carried in genes organized into strings made up of about 3 billion nucleotides.
The order of the building blocks, which come in different forms, is the code that carries hereditary information.