For many of us, memory is mysterious but largely unexamined. We don't think about it unless something threatens our memory. Stroke and Alzheimer's disease are feared partially because they attack memories, which help define us.
It's different for Mike Babcock, who went half way around the world last year to learn new techniques used to study memory.
Scientists like Babcock, a professor of psychology at Montana State University, have taken the study of memory from the functional level of organs to the activation of cells in the hippocampus, which is the part of our brain most active when we are creating certain types of memories.
Babcock spent much of last year working in New Zealand with researcher Cliff Abraham. Abraham's lab is "looking at memory from a different angle than my group," says Babcock. Working with living rodents, the researchers stimulate an area of the rat's hippocampus and then record how the hippocampus functions with additional stimulation.
"He has animals that show long-term potentiation of the neural circuits thought to be involved in memory for up to a year after the original stimulation," Babcock says. "Their response to future stimulation is more efficient. They are better at responding and the response is greater each time."
Babcock's main interest is to contribute to a better understanding of why the human hippocampus is sensitive to blockage of the blood supply to the brain, as happens when a person has a stroke. If we understand how brain cells are damaged, we stand a better chance of preventing that damage.
In humans, work often is done with a person who has had a traumatic injury to the brain. By looking at what area of a human brain was damaged and how that person's ability to remember changes, the scientists validate or reject the generalizations suggested by working with animal models.
The research so far shows that during stroke, abnormally high levels of the neurotransmitter glutamate is released, initiating a cascade of events that leads to the death of nerve cells in the hippocampus.
One reason the hippocampus is hit so hard by stroke is that it is "exquisitely sensitive" to input, probably because it was designed to record what happens to us so that we can learn from our experiences, says Babcock. The hippocampus is a bit like a muscle, getting larger as it is used more.
"A study of taxi drivers in London showed they have very large hippocampi," Babcock said.
Piece by piece, Babcock and other scientists are learning how we remember. Such work may look exciting, but he describes it as "a lot of work for the occasional success."
Babcock says he is "very thankful to be in this line of work because as scientists we're constantly learning new things. The research shows that that kind of stimulation is good for the brain."
Contact: Mike Babcock (406) 994-5175