Why Do We Forget? - Understanding the Phenomenon of Forgetfulness

This article explores the different theories and explanations behind forgetfulness, including decay theory, interference theory, and representation theory. It also discusses the role of the hippocampus, age, cognitive performance, and education levels in forgetfulness. Additionally, it highlights how forgetfulness can be advantageous and even an evolutionary trait.

Running head: Why do we forget?
Why Do We Forget?
Name of the Student
Name of the University
Author Note

1Why do we forget?
Why Do We Forget?
Memory is a mental faculty that allows the storage, encoding and retrieval of
information (gathered from learning, experiences, and sensory stimuli) [1]. Based on the type
of information stored, memory can be of different types: sensory, short term, long term,
episodic, topographic, declarative, procedural, prospective and retrospective memory. The
brain centers mainly considered to be responsible for the formation of memories include the
hippocampus, amygdale, striatum and mammilary bodies [2; 3]. Forgetting is the failure or
the inability to retrieve or remember one’s memories. Various theories and explanations exist
that explains the phenomenon of forgetfulness.
Decay Theory:
According to this theory, our memory slowly decays with time, slowly fading, for not
having being accessed over time [4]. This phenomenon can be compared to messages written
in the sand, where every wave of the ocean slowly erodes the message away, until noting of
the message ultimately remains.
Interference Theory:
This theory posits that memories can be made less accessible due to interference from
similar memories or information, which was acquired before or after the formation of the said
memory. This suggests one memory can be influenced by another similar, but possibly
stronger memory [5]. In the context of the previous analogy, this phenomenon can be
understood as the message written in the sand becoming undecipherable, after someone else
writes another message on top of it. Thus the original message gets overwritten and
inaccessible, in other words, forgotten [6].

2Why do we forget?
Interference of memories can also be differentiated into two types: proactive interference and
retroactive interference. Proactive interference occurs when the formation or retrieval of new
memories are impeded or prevented by an older memory. Retroactive memory occurs when
previously learned memories cannot be retrieved due to a new memory [5].
Representation theory:
This theory suggests that the decay theory and interference theories are not mutually
exclusive, and both are vital to understand forgetfulness. The theory is based upon how
memories are represented in our minds, pointing out that the main reason for forgetfulness
depends on the nature of the memory formed initially. Studies suggested that memory can be
related to two types of representations in our mind: recollection and familiarity. Familiarity is
a type of representation of memories where the specific details or the contexts are not
remembered, often seen in cases of familiar faces where the person would seem very familiar,
but hard to recollect the name. In comparison, recollection is another representation of
memories that have contexts and specific details, such as names [2].
Role of Hippocampus:
Studies show that the two types of memory representations (discussed above) behave
differently and also look different in the brain. Each of this representation has differential
dependencies on the hippocampus (a brain center vital in the process of memory formation).
Memories represented by recollections, inside the hippocampus are comparatively resistant to
interference from each other. Their forgetting is mainly due to decay. In comparison,
memories represented by familiarity are mainly supported by the extrahippocampal structures
and are prone to interference. So in the previously used analogy, a person who looks familiar
is a message prone to be overwritten by another message over time, while recollections of a
particular event would just fade away with time [3].

3Why do we forget?
Inability to store information:
Due to failures to encode information, it might not enter the long term memory, which
would make it susceptible to be forgotten [1]. Encoding failure can also cause incorrect
encoding of information which can cause the memory to be misrepresented and thus also
make it prone for decay or interference [7]. The analogy would be the message tried to be
written on a concrete surface instead of the sea beach, but with the same equipments, making
it impossible for the message to be etched in the first place or an incorrect message is being
written.
Motivated forgetfulness:
At times forgetting certain memories might be actively sought after, like that of
disturbing or traumatic memories. The motivated forgetfulness can be of two types:
conscious forgetting and unconscious forgetting. The former involves a conscious effort in
the attempt to forget or cause interference to a certain memory, while unconscious
forgetfulness refers to the involuntary and unconscious process that leads to the decay or
interference of the memory [8].
Accelerated Long Term Forgetting:
This refers to an abnormal forgetting in a span of hours or weeks, despite the memory
being normally acquired. The memories are encoded and retained normally for up to 30
minutes, but are then forgotten abnormally at a quick pace. This phenomenon was first
reported among people with epilepsy, especially, temporal lobe epilepsy. Further studies
termed the phenomenon as long term amnesia [9; 10; 11].
Age:

4Why do we forget?
Age is a significant factor related to memory. Some studies have proposed that with
advancing age, the forgetfulness increases, and information are converted to long term
memory more slowly. Also the rate of forgetfulness among older adults was linked to the
type of information they needed to remember. It was found that complex visual scenes were
more prone to be forgotten after a delay of 4 weeks among older adults, compared to their
younger counterparts. In studies, it was found that the source memories were the primary
problem for older adults, which increased the probability of the information to be forgotten.
This shows that with progressing age, the performance of the memory can slowly decrease,
and facilitate forgetfulness [12; 13].
General Cognitive Performance and Educational Background:
A positive correlation has been found between the intellectual performance of people
and memory. This implies that the intellectual function plays an important role in the
formation of memories, and that people with higher IQ tend to remember things better and
lower IQ increases the propensity to forget things. Tests show that people with higher IQ
were able to make more associations and better organization of information, thereby allowing
the information to be remembered. Similarly, it was also found that people with higher level
education can remember more information [14; 15]. Thus cognitive dysfunctions, and a lack
of education can increase the chances of forgetting information.
Forgetfulness is Advantageous:
Studies have also indicated that forgetfulness can have practical benefits for
individuals and might even by a product of the natural selection. Understanding how
forgetfulness can be advantageous, can help us comprehend why we forget information, and
how it is evolutionarily significant [16; 17; 18].

5Why do we forget?
1. Helping us survive trauma and painful experiences:
Memories of traumatic and painful experiences can cause stress, which in turn can
affect the physical and psychological wellbeing of people. With time these memories
however decays and diminishes in its details, making it inaccessible progressively, thereby
leading towards the memory being forgotten [19].
Specific neurotransmitters in our brain called the cannabinoid neurotransmitters play a
key role in the dampening the effects of the memories and focusing more on the present. The
system of cannabinoid transmitted increases the sensory experience and prevents the
intrusions or interferences from memories. The presence of this neurotransmitter further
proves that phenomenon of forgetfulness have been structurally woven into our
neuroanatomy through the system of the cannabinoid neurotransmitters, and thus is an
evolutionary trait [20].
2. Selective Memory:
For practical purposes, our memory is selective to decide which memories to save and
which ones to forget. In our day to day life, not everything that we see is remembered, and
fine details of events are generally missed, until a person consciously focuses on that detail.
Due to this we are unable to recall small details that skip our observation. Overall, we
remember the jest or an abstract form of the information, which is generally enough to give
us an understanding of it. Selective memory allows us an easy way to remember a wider
array of events, without overwhelming us with too much information. Studies have shown
that remembering too much details or specifics of an event can slow down the processing of
information to the point of incapacitating the natural thinking process [21]. This have been
seen in cases of people who have the ability to remember every bit of information they
encounter (also known as Mnemonist), as studied in the book, The Mind of a Mnemonist.

6Why do we forget?
Even though the Mnemonist are able to recall exact refries of words, numbers or images
presented to them to test their memory, in exact order, they also find it difficult to get rid of
trivial information, preventing them to focus on important or relevant information [22].
3. Memory enhancement:
Forgetting some old and outdated information can also allow the recollection of new
and relevant information. For example old passwords, pin codes, which are replaced are no
longer needed to be remembered, and are replaced with the newer information, which takes
its place. Even when learning a new language, it is useful to suppress the memories of the
native language, which can interfere with the learning of the new one. This is especially so in
case of two completely different languages with different grammar and structure [17; 18].
Conclusion:
Memory is a mental faculty that is associated with the storage and retrieval of
information of past experiences and events, and can be of different types based on the
information being stored. The process involves specific brain centers such as the
hippocampus and amygdale, which takes a central role in how we remember and forget
things. Different theories explain how memories might be lost or forgotten, and include decay
theory, interference theory and representation theory. Other factors that are associated with
forgetfulness are the functions of the hippocampus, inability to store information properly,
motivated forgetfulness, accelerated long term forgetting, as well as age, cognitive
performance and education levels of a person. Forgetting can also be seen as an evolutionary
trait that helps the survivors of traumatic or painful experiences forget the incident and
moving forward, it helps in the relevant memories to be better accessible, allows memories to
be more selective and also enhances relevant memories.

7Why do we forget?
References:
1. Hinton, Geoffrey E., and James A. Anderson, eds. Parallel models of associative
memory: updated edition. Psychology press, 2014.
2. Ortony, Andrew, and David E. Rumelhart. "The Representation of Knowledge in
Memory 1." Schooling and the acquisition of knowledge. Routledge, 2017. 99-135.
3. Koenig, Katherine A., et al. "The role of the thalamus and hippocampus in episodic
memory performance in patients with multiple sclerosis." Multiple Sclerosis
Journal (2018): 1352458518760716.
4. Ricker, Timothy J., Evie Vergauwe, and Nelson Cowan. "Decay theory of immediate
memory: From Brown (1958) to today (2014)." The Quarterly Journal of
Experimental Psychology 69.10 (2016): 1969-1995.
5. Anderson, John R., and Gordon H. Bower. Human associative memory. Psychology
press, 2014.
6. Bouton, Mark E. "Context, time, and memory retrieval in the interference paradigms
of Pavlovian learning." Psychological bulletin 114.1 (1993): 80.
7. Ferrarelli, Leslie K. "Active forgetfulness." Sci. Signal. 9.433 (2016): ec144-ec144.
8. Thakkar, Jay, Julie Redfern, and Clara K. Chow. "Text Messaging and Medication
Adherence—Do We Have a Missed Call?—Reply." JAMA internal medicine 176.8
(2016): 1227-1227.
9. Savage, Sharon, et al. "The evolution of accelerated long-term forgetting: Evidence
from the TIME study." Cortex (2017).

8Why do we forget?
10. Zimmermann, Jacqueline F., and Christopher R. Butler. "Accelerated long-term
forgetting in asymptomatic APOE ε4 carriers." The Lancet Neurology 17.5 (2018):
394-395.
11. Witt, Juri-Alexander, et al. "Loss of autonoetic awareness of recent autobiographical
episodes and accelerated long-term forgetting in a patient with previously
unrecognized glutamic acid decarboxylase antibody related limbic
encephalitis." Frontiers in neurology 6 (2015): 130.
12. Gold, Paul E., and Donna L. Korol. "Forgetfulness during aging: An integrated
biology." Neurobiology of learning and memory 112 (2014): 130-138.
13. McGill, Natalie. "Memory loss: Just a sign of aging, or something more?." (2017):
11-11.
14. Markant, Julie, and Dima Amso. "Leveling the playing field: Attention mitigates the
effects of intelligence on memory." Cognition 131.2 (2014): 195-204.
15. McLaren, Molly E., et al. "Impact of education on memory deficits in subclinical
depression." Archives of Clinical Neuropsychology 30.5 (2015): 387-393.
16. Anderson, Jacqueline FI, et al. "Individual differences in retrieval-induced forgetting
affect the impact of frontal dysfunction on retrieval-induced forgetting." Journal of
clinical and experimental neuropsychology 37.2 (2015): 140-151.
17. Popov, Vencislav, et al. "Forgetting is a Feature, not a Bug: Intentionally Forgetting
Some Things Helps Us Remember Others by Freeing up Working Memory
Resources." (2018).

9Why do we forget?
18. Sahakyan, Lili, and Nathaniel L. Foster. "The need for metaforgetting: Insights from
directed forgetting." The Oxford Handbook of Metamemory (2016): 341.
19. Storm, Benjamin C., et al. "A review of retrieval-induced forgetting in the contexts of
learning, eyewitness memory, social cognition, autobiographical memory, and
creative cognition." Psychology of Learning and Motivation. Vol. 62. Academic
Press, 2015. 141-194.
20. Muzaini, Hamzah. "On the matter of forgetting and ‘memory returns’." Transactions
of the Institute of British Geographers40.1 (2015): 102-112.
21. Bäuml, Karl-Heinz T., Alp Aslan, and Magdalena Abel. "The two faces of selective
memory retrieval—cognitive, developmental, and social processes." Psychology of
learning and motivation. Vol. 66. Academic Press, 2017. 167-209.
22. Brandt, Jason, and Arnold Bakker. "Neuropsychological investigation of “the
amazing memory man”." Neuropsychology 32.3 (2018): 304.