October 11, 2012
False Memories Implanted In your Brain
It sounds like something from a sci fi movie. You discover that your memories aren’t real – they have been implanted in your brain by someone who doesn’t want you to know the truth about your past. Your loving family never existed. The town that you grew up in was just a figment of your imagination.
You have a while to wait before you will be forced to commit horrible crimes and then have your memory altered so that you cannot confess to them under torture. However, scientists have taken a step toward creating artificial memories.
Ben Strowbridge and Robert Hyde at Case Western Reserve University School of Medicine have been able to create artificial short-term memories in rat brain tissue.
In an experiment, the researchers activated neural pathways in slices of rat brains, choosing between one of four input pathways. A memory of which input pathway was activated was retained by neural circuits in the hippocampus, the part of the brain associated with the transfer of information between short-term and long-term memory. These induced memories lasted for more than ten seconds.
The researchers were able to tell which pathways in the hippocampus were stimulated by looking at how brain cell activity changed.
If they activated different pathways in a sequence, the hippocampus retained a memory of the sequence and was able to differentiate between different sequences, showing that neural circuits n the hippocampus store information about context.
In previous studies of monkeys given short-term memory tasks, memory-related changes in activity in the monkeys’ brains lasted between five and ten seconds.
Strowbridge and Hyde were studying how declarative memories are formed. Declarative memories are memories of facts, such as what you had for breakfast, the name of the capital of Spain or the date of your parent’s wedding anniversary. They are called declarative memories because they involve facts that can be put into words.
Declarative memories differ from procedural memories, which are memories of how to perform physical activities like walking, driving, playing the guitar or catching a ball.
The researchers hope that studies like theirs will help scientists to understand how to prevent memory decline with age and how memory is affected by neurodegenerative diseases, such as Alzheimer’s disease and Parkinson’s disease.
As life expectancy increases and our population ages, learning how to prevent age-related memory problems becomes increasingly important. In the near future, people will have to work longer, and they will have to be capable of performing difficult mental tasks beyond the age at which their parents would have retired. Societies will not be able to fund the care for huge numbers of elderly people who are unable to care for themselves because of the inability to form or retain memories.
Studies have shown that aerobic exercise increases the volume of the hippocampus in elderly people, that memory training improves memory ability and hippocampal function in people with mild cognitive decline and that green tea prevents age-related changes to the hippocampus in rats.
The volume of the hippocampus is greatly reduced in people with Alzheimer’s disease.
By learning how memories are made and how memory ability can be improved, scientists can help us to remain self-sufficient as we grow older.
Then, some of us can learn how to alter other people’s memories so we can take over the world.
Image Credit: Photos.com