Summary: New research shows that we can distinguish between accurate memories and those filled with general knowledge. A study revealed that when memories are based on ‘prototypical’ information, our confidence in them decreases. This awareness helps us accurately assess the reliability of our recollections. These findings have significant implications for the credibility of eyewitness accounts in legal cases.
Key Facts:
- We can differentiate between accurate memories and those filled with general knowledge.
- Confidence in memory declines when it includes more ‘prototypical’ information.
- This self-awareness aids in assessing the reliability of our recollections, crucial for legal eyewitness accounts.
Source: University of Birmingham
How much trust should we put in our memories? New research shows we have a good awareness of when we are recalling events accurately – and when our brain is filling in gaps with general knowledge.
Memories are a blend of recalled details and ‘prototypical’ information, but a study at the University of Birmingham has shown that when prototypes appear more prominent, we become less confident in the recollection.
This means that we are able to distinguish between these two types of memory, and accurately assess how reliable our memories are. The results are published in Communications Psychology.
“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 to only retain the unique elements – some roadworks, perhaps, or a near-miss. The rest of the details are filled in from pre-existing knowledge.
“We wanted to find out well people were able to recognise these generic or ‘prototypical’ memories, and how far they were able to trust their recollections.”
In the study, just over 200 participants completed a series of experiments in which they were asked to look at objects in different ‘non-matching’ colours. For example a blue apple. After completing a simple maths task as a distraction, they were asked to remember the colour and then pick it out from a colour bar to test how precisely they were able to recall the shade.
Finally, they were asked to rate how confident they were of the accuracy of their answer by selecting from ‘sure’, ‘unsure’, or ‘guess’.
The group used unsupervised machine learning to pick out patterns from the responses. This enabled the researchers to spot the generic, or ‘prototypical’ shades that people tended to opt for when they were unsure of their accurate recollection of the colour.
The results showed that participants’ confidence in their colour selections tended to decline when the colours 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 have implications for eyewitness accounts in legal cases, where confidence in the accuracy of recollection is key.
Dr Griffiths added: “When it comes to facial recognition, we know that people struggle to distinguish accurate memories from prototypes. We know less about how recollection of events can also be biased, but that is equally important when making decisions about how much to trust an individual’s recollection.
“Our research shows 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.”
About this memory and neuroscience research news
Author: Beck Lockwood
Source: University of Birmingham
Contact: Beck Lockwood – University of Birmingham
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Metacognitive awareness of memory distortion during recall” by Ben Griffiths et al. Communications Psychology
Abstract
Metacognitive awareness of memory distortion during recall
When we recall a past event, we reconstruct the event based on a combination of episodic details and semantic knowledge (e.g., prototypes). Though prototypes can impair the veracity of recall, it remains unclear whether we are metacognitively aware of the distortions they introduce.
To address this, we conducted six experiments in which participants learned object-colour/object-location pairs and subsequently recalled the colour/location when cued with the object.
Leveraging unsupervised machine learning algorithms, we extracted participant-specific prototypes and embedded responses in two-dimensional space to quantify prototype-based distortions in individual memory traces.
Our findings reveal robust and conceptually replicable evidence to suggest that prototype-based distortion is accompanied by a reduction in self-reported confidence – an implicit measure of metacognitive awareness.
Critically, we find evidence to suggest that it is prototype-based distortion of a memory trace that undermines confidence, rather than a lack of confidence biasing reconstruction towards the use of prototypes.
Collectively, these findings suggest that we possess metacognitive awareness of distortions embedded in our memories.
