Scientists from the Universtiy Of Indiana have reported that they have found the first evidence that animals can recreate memory events. This discovery can help create new drugs to treat Alzheimer’s disease. The study, led by Professor Jonathon Crystal, has recently appeared in the journal of Current Biology.
“The reason we are interested in the memory of animals is not just to understand them but also to develop new memory models that match the types of memory that occur in medical cases, such as Alzheimer’s disease,” said Crystal.
“We are interested in episodic memory, and this plays an important role because it deteriorates in Alzheimer’s disease and aging in general,” said Danielle Panoz-Brown, a Ph.D. student at the University of Indiana and the lead author of the study.
To analyze this type of memory in animals, the researchers spent almost a year working with 13 rats
Scientists trained rats to memorize a list of 12 different odors. They were then placed in an “arena” with different odors and received rewards when they identified the penultimate smell or the fourth smell at the tail of the list.
The team changed the number of smells on the list before each test, in order to confirm that they were identified based on the position on the list, proving that the animals relied on their ability to remember the entire list in order. Areas of different patterns were used to communicate with the rats looking for the two options.
After training, the animals could successfully complete their job in 87% of the time in all experiments. The results are strong evidence that animals use memory episodes.
Other experiments confirmed that the memory of the rats was long-lasting and resistant to the “interference” of other memories, both marking episodic memory. The scientists also carried out tests that temporarily inhibited the activity of the hippocampus – the episodic memory spot in the brain – to confirm that rodents used this part of the brain.