Randy Buckner is fascinated by how we form memories and retrieve them. He decided to become a “mind reader” to capture the fleeting process we take for granted when we hear a song or read a book and then can recall the melody or the story hours later.

In the late 1990s, Buckner improved an imaging method so researchers could peer into a living brain and observe a memory materializing in a few seconds. Prior approaches could only detect events that occurred during a 30- to 90-second interval, making it impossible to see more ephemeral memory creations and recollections.

His invention, event-related functional magnetic resonance imaging (fMRI), now routinely used by neuroscientists, revolutionized the study of human memory and other mental activities. Today, Buckner continues to adapt new imaging methods and behavioral tests to study brain regions implicated in normal memory. He also investigates memory deficits in the healthy elderly and in those afflicted with Alzheimer’s disease.

To do a memory study, Buckner might ask a subject to memorize a list of words while his or her brain is scanned by an fMRI device. Later, outside of the device, he tests the individual’s ability to remember each word. MRI scanners produce a large magnetic field that moves hydrogen atoms in a certain direction in the tissue. As the atoms return to their original position, they release radio waves that are then converted to images. The pictures reveal blood flow to stimulated areas in the brain, such as those used to memorize the words.

One of Buckner’s most significant findings using this approach was the identification of specific regions of the brain, in the frontal and temporal lobes, that can predict if someone will remember a word. After analysis of the brain images and performance of many subjects, Buckner was able to determine from the brain patterns observed during memorization if a subject would remember certain words. Essentially, he was able to read their minds.

The frontal lobes sit at the front of the brain, with the left lobe implicated in verbal activity and the right lobe in nonverbal activity. The temporal lobes are above each ear and are involved in the processing of sound, speech, and images and in memory.

Buckner continues to analyze in great detail the frontal lobe brain regions used during memory. Some of his research has shown that as more frontal lobe areas are recruited, memory performance improves. Training people to use multiple frontal lobe regions may enhance memory, he says.

Buckner additionally studies memory loss in healthy seniors and memory dysfunction in Alzheimer’s patients. A question for neuroscientists studying age and memory has been whether memory changes that occur during normal aging build up, leading to some severity of impairment and then to Alzheimer’s disease.

Buckner’s research suggests that memory loss in normal aging and memory loss in Alzheimer’s are different. His has found what he calls distinct cascades, or patterns, in the brain in aging and in Alzheimer’s. In normal aging, he sees major changes in white matter, a network of cable-like extensions from nerve cells that connect different regions of the brain’s gray matter, which is composed of nerve cell bodies. The cables seem to help synchronize activity in different brain regions. If they are impaired, coordination suffers.

In Alzheimer’s, changes occur in the white matter (toward the posterior of the brain), but cells also are dying in the temporal lobes, leading to significant memory losses.

One goal of Buckner’s research is to detect Alzheimer’s disease in the brains of elderly people before they develop symptoms. If there were a way to see early disease, clinicians and investigators would be able to monitor the effects of interventions that might either delay or prevent the patient’s decline

Buckner recently started using a new molecular marker, developed by researchers at the University of Pittsburgh in 2005, that can identify the biomolecule amyloid in a living brain. Amyloid is the major constituent of plaques, a hallmark of the pathology in the brains of Alzheimer’s disease patients. Before, scientists and clinicians only saw plaques in brain tissue from autopsies of Alzheimer’s patients.

Using the amyloid marker, Buckner has found that some elderly people, particularly the highly educated, can have plaques in their brains but remain asymptomatic for Alzheimer’s. Buckner also has found that healthy elderly people can draw on reserves to overcome the damage their brains experience during their lifetime. He is trying to understand the compensatory brain mechanisms both these groups use. Replicating such strategies might improve memory function in the healthy elderly or defer disease in those with the amyloid marker, he says.

Brain-imaging advances are finally allowing neuroscientists to distinguish, for the first time, the aging brain from the Alzheimer’s brain, Buckner says. In the past, when researchers studied memory in normal aging, they probably had in their samples people whose early Alzheimer’s disease was undetected, confounding the results.

With all of the new methods to study normal memory, and aging and Alzheimer’s brains, Bucker hopes that in the future, as more of us continue live into our 90s, we will be able to do so with our memories intact.