Scientists discover how we compress memories
Scientists from the University of Texas at Austin discovered how our brains compress our memories and how it affects people with Alzheimer’s and schizophrenia.
Compressing thoughts helps us play memories in fast forward—like how we can remember events in day or plan a day in just five minutes.
The newly discovered mechanism, which compresses information needed for memory retrieval, imagination or planning and encodes it on a brain wave frequency that’s separate from the one used for recording real-time experiences, is described in a cover article in the Jan. 20 print edition of the journal Neuron.
Brain cells share different kinds of information with one another using a variety of different brain waves, analogous to the way radio stations broadcast on different frequencies. Laura Colgin, an assistant professor of neuroscience, Chenguang Zheng, a postdoctoral researcher, and their colleagues found that one of these frequencies allows us to play back memories — or envision future activities — in fast forward.
Mental compression turns out to be similar to what happens in a computer when you compress a file. Just like digital compression, when you replay a mental memory or imagine an upcoming sequence of events, these thoughts will have less of the rich detail found in the source material. The finding has implications for medicine as well as for criminal justice and other areas where memory reliability can be at issue.
Colgin notes that the research could also explain why people with schizophrenia who are experiencing disrupted gamma rhythms have a hard time distinguishing between imagined and real experiences.
“Maybe they are transmitting their own imagined thoughts on the wrong frequency, the one usually reserved for things that are really happening,” says Colgin. “That could have terrible consequences.”
Next, the researchers plan to use animals with neurological disorders similar to autism spectrum disorders and Alzheimer’s disease in humans to better understand what role this mechanism plays and explore ways to counteract it.
