Our brains change as we age, and connections between the different parts of the brain become less efficient. This explains why learning new things is more challenging for older people, according to Pernilla Andersson's doctoral thesis in psychology at örebro University.
Our brains help us forget information we no longer need, making room for newer, more relevant knowledge that we may find more useful. As we age, this ability diminishes, and old information can instead "interfere" with our working memory when we try to learn new things. This form of memory impairment is known as proactive interference.
Pernilla Andersson researches cognitive neuroscience at örebro University, and her thesis examines what happens to the brain's structure and function resulting from such memory impairments.
Results show that older people with memory impairments have poorer communication between different regions in the brain. They also tend to have lower quality in the fibres connecting these brain regions.
"These connections are important for different brain regions to communicate with each other. When the quality is lower, it can affect how efficient and fast the communication is," explains Pernilla Andersson.
Her research also shows that changes in the hippocampus, a brain region central to memory, seem to play a critical role in how well we can manage memory impairments as we age.
"When the hippocampus shrinks, the risk of proactive interference increases in older age. The hippocampus plays an important role in noting the context in which certain information or events occur."
This knowledge provides essential pieces to the puzzle of understanding why our memory deteriorates as we age and why it is harder for older people to learn new things.
So far, there are no concrete recommendations on how to reduce the risk of memory impairments and decreased working memory in old age.
It's an area that's still quite unexplored. There's one study showing that mindfulness can have a positive effect on the ability to control proactive interference. But much more research is needed on aging."
Pernilla Andersson
It is still not fully understood what determines whether someone experiences a decline in memory function as they age.
"There's a wide variation in cognitive aging, where we've observed that some people continue to perform as if they were younger. It's an area I'd like to continue researching," says Pernilla Andersson.
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