By John Salak –
The hard reality is that an awful lot of people will experience some form of memory loss, especially as they age. These lapses aren’t always—or even usually—caused by cognitive diseases like Alzheimer’s. Rather, most memory issues are a natural function of aging with various lifestyle considerations potentially adding to the issues.
Problems, in fact, start earlier than many assume. The Centers for Disease Control and Prevention reports that 10 percent of people over 40 experience some memory loss, while another well-reported study claims that 40 percent of people 65 and older are likely to lose some memory function.
This seemingly inevitable decline begs the question of whether people can trust what they do remember. Apparently, they can, at least according to a British research team.
The University of Birmingham reports that people generally a have a good awareness of when they are recalling events accurately—and when their brain is filling in gaps with general knowledge.
It is not unusual for memories to be a blend of recalled details and ‘prototypical’ information, but the university’s research revealed that when prototypes appear more prominent, people become less confident in the recollection. The results demonstrate that people are able to distinguish between these two types of memory. More importantly, they can accurately assess how reliable their memories are.
“We rely on our memories, particularly when they are of a one-off event, for example, a birthday dinner,” explained lead author Dr. Ben Griffiths. “But events that occur regularly, such as your commute to work, are streamlined by the brain only to retain the unique elements—some roadworks, perhaps, or a near-miss. The rest of the details are filled in from pre-existing knowledge.”
The researchers wanted to determine how well people recognize these generic or ‘prototypical’ memories. In addition, they sought to discover how far people were able to trust their recollections.”
The university’s effort involved more than 200 participants completing a series of experiments in which they were asked to look at objects in different non-matching colors.
The process required them to complete a simple math task as a distraction, then remember the related color and then pick it out from a color bar to test how precisely they were able to recall the shade. The final aspect involved the participants rating how confident they were of the accuracy of their answer by selecting from ‘sure’, ‘unsure’, or ‘guess’.
The results showed that participants’ confidence in their color selections tended to decline when the colors were closer to shades identified as prototypical by the machine learning algorithm. This suggests that we are aware of the likely degree to which prototypes are filling in gaps in our memory and can factor in that knowledge when we are asked to assess the accuracy of our recollection.
The findings could have implications for eyewitness accounts in legal cases, where confidence in the accuracy of recollection is key, Griffins explained.
“When it comes to facial recognition, we know that people struggle to distinguish accurate memories from prototypes. We know less about how the recollection of events can also be biased, but that is equally important when making decisions about how much to trust an individual’s recollection,” he said.
The results are significant because they show “that people are actually quite good at knowing when their accounts are reliable and when they are influenced by their brain filling in gaps with generic information,” Griffins concluded.
