Are all memories created equal? It is almost certain that different people have different brain capabilities for different things. One of these differences must be in memory. But most of the differences in memory capabilities that we see in everyday life do not seem to be due to differences in the brains we are born with, but to differences in how well we use the brains we are born with.
Our brains are perhaps somewhat like our muscles: everybody is born with different amounts of muscle. And this is perhaps mostly true of the muscle that is your heart. So it is likely that some people have bigger, stronger hearts than others do at birth.
But it is also true that many people can take whatever amount of heart they are born with – large or smallâ€”and train themselves up from couch potato to marathon runner. The dissimilarities we find in everyday memory probably are similar.
They are probably still mostly based on how much we exercise what we have, not how much memory we are born with. This is not to diminish the fact that different people may be born with different memory abilities.
Genetically Based Differences
We know or suspect that there are genetically-based differences in brains. Some of the proof comes from identical twins. Identical twins are almost exactly similar in their genetic composition. And identical twins show remarkably similar intelligence and memory abilities, even when they have been separated at birth and reared by different parents, in different atmospheres.
They even show outstandingly similar patterns of how those intellectual capabilities develop childhood and adolescence. These similarities suggest that there is a genetic program for intelligence and memory that partly decides the intelligence and memory that we have in later life.
At the brain level, less is actually known about actual individual differences in the brain, and even less is known about individual differences in nerve cell connections. But these also certainly exist.
For instance, an area of the cortex of the brain – the gray matter – is the first stop for information coming from the eyes. This area of the brain is clearly important in vision. Species with good vision have more of it; species that lose their vision lose this brain region.
On the average, in humans, this brain region is three to four times larger than it is in monkeys – some reflection of our superior brain power, we would hope. But we also know that in some people, this area can be three times larger than it is in other people.
Lifestyle Affects Memory Performance
Why does how we live from day to day affect our memory performance? Very simply, memory is part of who we are. It does not subsist in a protected “black box” in our heads; rather, memory is a fundamental aspect of our physical and mental functioning.
Therefore, we may see an impact on our memory ability if we are not taking care of ourselves – for instance, not getting adequate rest, or feeling very anxious. Many people are unaware that their lifestyle choices matter until they become concerned about how well they are remembering. But when they realize how those choices affect memory, they are motivated to change them.
How do these features of daily life affect our memory? In general, poor lifestyle options compromise our memory potential by making it harder for us to focus our attention. Since attention is one of the most sensitive aspects of our intellectual functioning, it is quite susceptible to influence from the ups and downs of everyday living.
Attention is central to memory, and we must be able to attend to information in order to obtain it. Factors in our lifestyle, for that reason, can make it harder for us to focus on information and obtain it efficiently.