As we age, most people report some issues with their memory. But why is this the case? According to researchers from the Georgia Institute of Technology it could all be down to ‘clutter’.
As a result of their findings, the researchers concluded that older people may have problems remembering important details because their brains subconsciously remember all kinds of irrelevant details. This makes them less confident in the memories they do have.
To arrive at this conclusion, the Georgia team used EEG sensors to look at the brain activity of two groups of people. From this they observed that older participants spent longer trying to recall details, as they tried to extract them from a space cluttered with both relevant and irrelevant information. This led to less confidence in the accuracy of their memories, even when their recollections proved to be correct.
As part of the study, older adults aged 60 and above and a group of college students were shown images of everyday objects while their brain activity was monitored via EEG sensors. Each of the images was accompanied by a specific colour and scene. The participants were instructed to focus on one, while ignoring the other. After an hour they were asked questions about the images.
The researchers found that neither of the age groups found it easy to remember the things they’d been advised to ignore, although both age groups performed well when asked to remember the object and the colour or scene they’d been asked to focus on. However, when they were asked whether they were sure about what they remembered, the people in the older group were more likely to hesitate, and become unsure about their recollection.
Differences in brain activity between the two groups were also noted. The brains of the older adults appeared to be spending a greater amount of time and effort in reconstructing their memories. The older group seemed to spend longer going back in time trying to piece together what they’d seen. Furthermore, some of what they were told to ignore seemed to be stuck in their minds too.
The college students were quicker to remember details, and also used less brain activity to arrive at the answer. Their memories were kept relatively clutter-free due to the fact that they never stored the information they were told to ignore. This made them far more confident than the older group when it came to remembering the relevant details.
This ‘cluttering’ of the brain is likely to be one of the reasons why older people become more susceptible to manipulation and scams, particularly those where the victims are persuaded that a conversation has already taken place, when it hadn’t happened at all.
The study was published online in the journal Neuropsychologia.