A lot of people think that memory works like a recording device. Memory works a little bit more like a Wikipedia page: You can go in there and change it but so can other people.

-       Elizabeth Loftus

This article will cover:

·       How does our memory operate?

·       What are false memories?

·       What causes false memories?

·       Memory and eyewitness testimony

How does our memory operate?

Memory is our ability to process information, store it and retrieve it at a later time [10]. There are three key processes involved [8]. Encoding refers to processing the incoming information. Memory storage concerns the nature of the stored memory, its duration and the capacity of the memory system. Here we can make a distinction between three types of memory, sensory, short-term (STM) and long term (LTM) [2]. Sensory memory allows us to retain sensory information after the stimuli have disappeared. STM lasts for a brief period of time (around 20 seconds) and can hold approximately 7 items at a time. LTM can theoretically store an infinite amount of information that lasts for a very long time. Researchers identified multiple types of LTM. Explicit (declarative) memory requires conscious recall of information. It can further be divided into semantic, which stores facts or episodic, which stores events and experiences. On the contrary, implicit memory is unconscious and holds information about how to perform certain tasks or motor skills. Lastly, there is memory retrieval which is the process of remembering information stored in memory [8]. Sometimes, we can remember things that did not actually happen. This phenomenon is referred to as false memory.

Source: http://www.lukemastin.com/humanmemory/types.html

What are false memories?

Contrary to popular belief, memory is malleable, relatively easy to manipulate and often unreliable [2]. False memory is a fabricated or distorted recollection of an event that we believe happened [4]. They can either be entirely false, meaning that the event did not actually occur or contain pieces of information that are inaccurate. In real life (i.e., outside of lab experiments) false memories usually concern the part of our memory system called autobiographical memory [2]. This type of memory holds information about personal events. Unfortunately, unless clear evidence is available regarding the (non)occurrence of the event, it is difficult to recognise false memory [9].

What causes false memories?

Problems can occur at any stage of the memory process, from encoding to retrieval. These can ultimately lead to the formation of a false memory [4, 5]. Researchers propose several theories as an explanation for this phenomenon.

False memories might be a result of the post-event misinformation effect [1, 7]. You can be given false information about a specific event which can ultimately lead to a creation of a completely false memory of an event that never actually happened or that you never witnessed. It can also cause the fake information to be combined with a real memory that leads to recall of the manipulated, rather than the original memory. This is related to the so-called retroactive interference where information received after the event, and thus after the formation of the memory, influences the already existing memory [7].

Moreover, faulty source monitoring (source misattribution) may also contribute to the formation of false memories [1]. This means that our brain incorrectly identifies the source of information. This is most likely to happen when two events resemble each other. You might incorrectly combine circumstances of event A with circumstances of event B to create a memory of one singular event.

Furthermore, factors such as low IQ, low working memory capacity [12] or social pressure [7] may make people more prone to constructing false memories.

Memory and eyewitness testimony

Most of the time, false memories are fairly harmless, such as remembering that you turned on the washing machine when you actually did not. However, sometimes they can have serious consequences. One of the negative consequences of false memories is their influence on the reliability of eyewitness testimonies [3]. It is crucial to be aware of the unreliability of eyewitness memories because it can sometimes go as far as wrongful convictions based on inaccurate recollections of events and identification of perpetrators [6].  

Firstly, investigators can often ask leading questions [2]. These are questions that contain the answer or information that the investigator is looking for. They might result in false recollection of an event because the eyewitness incorporates the information provided by the interviewer into their memory of the event.

Additionally, the longer the time period between the crime and the recollection, the less accurate the recall is [11]. This is because the strength of the memory naturally decreases with time and thus the person becomes more vulnerable to the effects of misinformation and more prone to creating false memories.

An additional issue with the formation of the memory of the event is the weapon-focus effect [2]. This means that when the perpetrator has a weapon, the witness is likely to hyper-focus on this central detail and ignore the peripheral details (perpetrator’s characteristics). This can result in an inaccurate recall of perpetrator’s characteristics because they have not been properly processed in the first place.

Furthermore, the other-race effect [2] can influence facial recognition accuracy. Researchers suggest that person is better able to recognise and encode faces that match their own race. This may result in the incorrect encoding of racially ambiguous persons.

Lastly, the jurors sometimes tend to make decisions based on eyewitness’ confidence in their memory. However, there is only a small to moderate correlation between memory accuracy and a person’s confidence in the accuracy of their memory [7, 11].

In conclusion,

memory is complex in terms of structure and the way it operates. Unfortunately, it is not flawless. In fact, memory is very prone to mistakes such as creating false memories. The issues concerning the ‘failures’ of our memory are related to the reliability of eyewitness testimonies. Putting too much confidence into eyewitness testimonies can sometimes have far-reaching consequences.

Extra resources:

1. Podcast episode of ‘Bad People’: https://open.spotify.com/episode/1BzUlvsqeoa9ONIaqdu5XU?si=6M8tKpqmS3OQUvAc_f7Dlg

2. Book by Dr Julia Shaw: The Memory Illusion

3. Ted Talk by Elizabeth Loftus – How reliable is your memory? https://www.youtube.com/watch?v=PB2OegI6wvI

References

1.     Baddeley, A., Eysenck, M. W., & Anderson, M. C. (2015). Chapter 16. In Memory (2nd Edition).

2. Boundless Psychology. Introduction to Memory. Retrieved on November 11, 2021 from https://courses.lumenlearning.com/boundless-psychology/chapter/introduction-to-memory/

3.     Carpenter, A. C., & Krendl, A. C. (2018). Are eyewitness accounts biased? Evaluating false memories for crimes involving in-group or out-group conflict. Social neuroscience, 13(1), 74-93. https://doi.org/10.1080/17470919.2016.1253610

4. Cherry, K. (July 2020). False Memories. Retrieved on November 11, 2021 from https://www.verywellmind.com/what-is-a-false-memory-2795193

5. Holland, K. (April 2019). False Memory: What You Need to Know. Retrieved on November 11, 2021 from https://www.healthline.com/health/false-memory#false-memory-syndrome

6.     Loftus, E. F. (2018). Eyewitness science and the legal system. Annual review of law and social science, 14, 1-10.

7.     Matlin, M. W., & Farmer, T. A. (2017). Chapter 5. In Cognition (9th Edition).

8. McLeod, S. A. (2013, August 05). Stages of memory - encoding storage and retrieval. Simply Psychology. www.simplypsychology.org/memory.html

9. Psychology Today. False Memories. Retrieved on November 11, 2021 from https://www.psychologytoday.com/us/basics/false-memories

10.  Psychology Today. Memory Center. Retrieved on November 11, 2021 from https://www.psychologytoday.com/intl/basics/memory

11.  Rose, C., & Beck, V. (2016). Eyewitness accounts: false facts, false memories, and false identification. Journal of crime and justice, 39(2), 243-263. https://doi.org/10.1080/0735648X.2014.940999

12.  Zhu, B., Chen, C., Loftus, E. F., Lin, C., He, Q., Chen, C., ... & Dong, Q. (2010). Individual differences in false memory from misinformation: Cognitive factors. Memory, 18(5), 543-555. https://doi.org/10.1080/09658211.2010.487051