FRIDAY, July 28, 2006 (HealthDay News) -- Experiments where volunteers took an amnesia-inducing drug have brought new insight into how humans form memories.
The two-session study examined the ability of people to remember words, faces, landscapes, and abstract pictures. The study was conducted by researchers at Carnegie Mellon University and the University of Pittsburgh.
In one session, the study participants performed a memory exercise after they'd received an injection of a saline placebo. In the other session, they were given the drug midazolam, which is used to relieve anxiety during surgical procedures. The drug also causes short-term "anterograde" amnesia, the most common form of amnesia.
The study found that the drug hindered recollection, a process in which people retrieve contextual details (in this case, the study event) involved in the experience of studying information. But the drug did not affect the familiarity process, in which people recognize something that seems sufficiently familiar. They do this without using recollection.
The study authors noted that this same pattern is found in anterograde amnesia patients, who are unable to form new associations. This severely limits the accuracy of their recognition judgments.
"This helps us understand the general functions of memory. It helps us relate, for example, the memory declines seen in old age to those seen in patients with hippocampal damage," study lead author Lynne Reder, a professor of psychology and Carnegie Mellon, said in a prepared statement.
The study was published in the July issue of the journal Psychological Science.
More information
The U.S. National Library of Medicine has more about memory loss.
