- Subtle memory loss commonly occurs as we age.
- Much of aging cognitive changes are due to the changes in areas of the brain, such as the hippocampus.
- A new study found that the memory loss transition may occur in middle age.
- Researchers found older adult memory loss may be caused by reactivation of the hippocampus.
As we age, it is not uncommon to experience subtle cognitive changes, such as forgetfulness and subtle memory loss.
Now a new study published in the journal Cerebral Cortex reports that memory loss may begin earlier in life than we think. Researchers also shed light on why memory loss occurs in the first place.
For this study, researchers recruited 60 adults between the ages of 18 and 74. Study participants were all shown various pictures of objects and scenes associated with specific faces.
After a 5-minute rest period, participants were asked to take part in a memory test to measure how well they could pick the right object or scene associated with each face.
During the memory test, participants also underwent an MRI scan to view how their hippocampus worked during the test.
“This ability to remember pairs of items — similar to putting a name to a face — is largely controlled by the intactness of the hippocampus,” Ian McDonough, PhD, associate professor of psychology at Binghamton University and co-lead author of this study, told Medical News Today.
“This brain region binds or combines arbitrary pieces of information together and serves as the basis for most of our memories. Thus, this was a task that could help us better understand how the function and size of the hippocampus differs between young, middle, and older age,” McDonough explained.
At the study’s conclusion, researchers discovered that young adult participants (ages 20-30) and middle-aged participants (ages 50-63) experienced a large decline in memory accuracy, suggesting middle age may be the true memory transition point.
Additionally, when comparing how young adults versus older adults (ages 63-74) accessed their memories, scientists found that when young participants remembered things incorrectly, it was due to their brains not activating the original memory patterns.
However, when older adults made memory mistakes, their brains showed an increased reactivation of those memory patterns and their hippocampus.
“This was the most surprising finding of the study,” McDonough said. “Hippocampal reactivation in young adults is usually a sign that a vivid (and accurate) memory is being retrieved. In older adults, the same pattern of hippocampal reactivation that should be associated with good memories, are instead associated with less accurate memories.”
“This is important because it means the hippocampus is changing fundamental aspects about what it is doing in old age compared with young age,” he continued. ”We can’t simply assume that older adults’ brains do the same thing as young adults but ‘less’ of it. Instead, it is dynamically changing in ways that we still don’t fully understand.”
MNT had the opportunity to speak with Manisha Parulekar, MD, co-director for the Center for Memory Loss and Brain Health at Hackensack University Medical Center in New Jersey, who commented that this study is further validation that cognitive decline often starts developing long before symptoms appear.
“We often see patients in their 70s or 80s, when memory issues are prominent,” Parulekar, who was not involved in this study, explained. “This study confirms that the neurological shifts leading to memory loss may begin much earlier, showing a significant drop in memory accuracy by the time people reach their 50s.”
“What stood out to me most was why older and middle-aged brains are making mistakes. The researchers looked at three phases of memory: Learning the information, resting, and then trying to recall it. They found that the aging brain isn’t just ‘powering down’ or failing to activate. The aging brain remains highly active, but it starts to ‘misbind’ information. In young adults, high brain activity means a crisp, accurate memory.“
– Manisha Parulekar, MD
“But in older adults, that same high activity jumbles details together,” she added. “An older adult might confidently pair a familiar face with a landscape that was originally paired with a completely different category of image, like a coffee cup.“
“The researchers proved these specific errors weren’t simply caused by brain shrinkage but by a fundamental shift in how the brain’s memory center communicates with itself,” she concluded.
Andrew Tarulli, MD, a neurologist and chairman of neurology at Atlantic Health Overlook Medical Center in Summit, NJ, who likewise was not involved in this study, said he sees this study as an early step in developing a
“It is not yet ready for clinical use, but with further development this fMRI-based technique could supplement the techniques that we use today to evaluate patients with memory concerns,” Tarulli said.
“It is important to learn about the early stages of memory loss so that we can identify new therapies that could be employed earlier in the course of disease, which could slow or prevent clinical decline,” he pointed out.
“It would be interesting to retest patients and see how functional connectivity in the hippocampus changes with aging,” Tarulli added. “The hippocampus is not the sole structure involved in memory processing, and fMRI investigation of other areas of the cerebral cortex would also be valuable.”
For those who want to slow down and possibly prevent memory loss at any age, Zack Ramilevich, MD, a neurologist at Marcus Neuroscience Institute, part of Baptist Health South Florida, said there is no guaranteed way to prevent memory loss or dementia.
However, Ramilevich also advised that there are many things people can do throughout adulthood that support overall brain health, such as:
“I would also encourage people to know their numbers and work with their healthcare provider to control high blood pressure, diabetes, and cholesterol because what is good for the heart is generally good for the brain,” Ramilevich, who was not involved in this study, continued.
“Sleep is another important piece. Adults should aim for consistent, adequate sleep, and conditions such as sleep apnea should not be ignored,” he advised.
Finally, Dung Trinh, MD, an internist at MemorialCare Medical Group and chief medical officer of the Healthy Brain Clinic in Irvine, CA — who likewise was not involved in this study — urged people to not to wait until memory problems become severe before paying attention to brain health.
“Many of the things that protect cardiovascular health also appear to support brain health,” Trinh explained. “I would also encourage people to pay attention to change over time, rather than occasional forgetfulness.“
“Everyone forgets a name or misplaces something. What concerns us more is a persistent decline from a person’s previous level of functioning,” he emphasized. “For example, repeatedly forgetting important conversations, getting lost in familiar places, difficulty managing medications or finances, or family members noticing a meaningful change.”
“If that is happening, it is worth discussing with a primary-care physician. Evaluation can include cognitive testing, medication review, assessment of sleep and mood, laboratory testing for potentially reversible causes, and, when appropriate, referral for more specialized evaluation,” said Trinh.