What is Memory Bias?
Memory is a very complex phenomenon and it is not surprising that certain things affect how well we remember things. These are called ‘memory biases’ and they may impair or enhance the recall of a memory, for example affecting the chances of a memory being recalled at all or the amount of time it takes for you to recall that memory - or they may even alter the content of what’s remembered.
Types of Memory BiasA wide variety of memory biases have been recorded. These include:
- Humour effect – things we find humorous are more easily remembered, possibly because humour requires increased cognitive processing time to understand it or because it is linked with emotional arousal.
- Generation effect – information that is self-generated is remembered best.
- Levelling and sharpening – this occurs when memory is distorted due to loss of certain details over time, while simultaneously displaying the selective recollection or sharpening of certain other details which take on an exaggerated significance in relation to the information that is lost.
- Choice-supportive bias – this bias leads you to remember your chosen options as being better than rejected options.
- Hindsight bias – a similar phenomenon which leads you to see all past events as predictable and something you “knew all along”.
- Misattribution/Source Confusion – confusing the source of a memory so that it is attributed to something else; for example, claiming to have witnessed an event personally when it was actually seen on the TV. In other cases, the information of the memory is retained but the source of it is forgotten.
- Context effect – memories are easier to retrieve when you are in the same context; eg. studies show that work-related memories are recalled faster and more accurately in the workplace than at home.
- Positivity effect – older adults tend to favour positive information over the negative, in their memories.
- Picture-superiority effect – in many cases, concepts are better remembered if they are presented in picture form than in word form.
- Infantile amnesia – this leads you to retain very few memories before the age of 2 years.
- Rosy retrospection – the classic “rose-tinted memory” – this leads you to remember the past as having been better than it really was.
- Spacing effect – this describes the way that information is better retained if it has been exposed to you repeatedly over a period of time.
- Tip of tongue phenomenon- when you are able to recall parts of an item but unable to recollect all the details. This is believed to be due to “blocking” where multiple, similar memories are being retrieved at the same time and they interfere with each other.
- Consistency bias – this occurs when you incorrectly remember you past attitudes and behaviour as similar to your present ones.
- Reminiscence bump – this leads you to recall more personal events from adolescence and early adulthood than from other lifetime periods.
- Zeigarnik effect – when you remember interrupted or uncompleted tasks better than completed ones.
- Serial position effect – this causes you to remember the first and last items of a list more easily than items in the middle of the list.
- Telescoping effect – when someone shows the tendency to displace recent events backward in time so that recent events appear to be more remote.
- Cryptomnesia – this occurs when memory is confused with imagination, often because the person has no subjective experience of the memory.
While we are all subject to memory biases to some extent, it is good to be aware of them and to realise that memories are not as reliable as we think they are.