As you grow older, the ability to remember something — perhaps a small detail, perhaps someone’s name, perhaps where you parked the car — starts to dim. Your memory just ain’t what it used to be. This course of aging is well known, but a new health breakthrough may have uncovered why it has to be this way. It’s all about “new” information.
Our aging brains are unable to process information as “new,” because the pathways leading to the “hippocampus” become degraded over time. The hippocampus is where the brain stores memories. As a result, our brains cannot accurately “file” new information. Confusion results.
This is what researchers found using brain imaging techniques to see what happens with age. There is a reduced ability of that hippocampus to do its job. And older memories can interfere with new ones much more so than for younger people. It also helps explain why reminiscing is common — because older memories are easier to recall than what happened last week.
It came from a study of 40 young college students and adults aged 60 to 80. All viewed pictures of everyday objects, such as pineapples and tractors, classifying them as either “indoor” or “outdoor.” Some pictures were similar, while others were very different. Would people’s brains be able to view them as familiar?
For an older person, the pictures had to be very distinct for them to correctly classify them as new. If they were similar, an older person had struggles deciding whether each was old or new. The more similar the pictures were, the more the older person’s hippocampus struggled to do this. Further examinations showed that older people simply had far more trouble distinguishing between similar items., wondering if they had seen it before or not.
This “similar’ idea is key, as this is linked to the “perforant pathway,” which directs input from the brain into the hippocampus. The more degraded the pathway, the less likely the hippocampus is to store similar memories as distinct from old memories. This is a big step toward uncovering the reasons behind age-related memory loss. And the researchers hope it will help extend into a greater understanding of dementia — even treatment.