Introduction
Memories
underpin our conscious sense of awareness throughout our life. They form
the glue that binds humanity in the stories that we tell one another and in a
collective sense represent our history. The many multidisciplinary
studies into the nature of memories and how they are formed in the mind
have unlocked information that paints a different picture to what was once
thought. Therein we can liken memories to be more like an artist's impression
than a video that depicts every detail as we see it. These new revelations have
attracted the interests of philosophers, who define different types of memories
and ask the question how confident we can be about their accuracy?
The
question of reliability and the risk of false memories is what I want to
talk about in these notes. What are the risks of wrongly convicting innocent
victims or stigmatizing unjustly reputations? But to do justice to these
questions I need to understand the latest available research into how different
types of memories are created, stored and maintained in the modern brain.
Defining memory
First of
all I need to define memory as - ‘The past as it becomes known to form part of
me in my life’s existence.
Memories begin in the womb
Researcher’s
claim this process begins after only 3 weeks following fertilization.
Thereafter new neurons which make the central nervous system form at the rate
of 250,000 per minute. Development thereafter continues at this astonishing
pace so that significant milestones are achieved to mean the body weight of the
2 year old infant brain is 85% of its adult form.
Remarkably
both short and long term memory begin in the womb during this rapid formative
stage. But in a process that isn’t fully understood about half of that memory
is discarded after birth. The suggestion is this optimizes rapid absorption of
the incoming stimuli to ensure future optimum memory creation.
Following
birth this process continues, but from the ages ranging between 2 to 7 we have
no recollections of these early memories. The Science of Memory 2nd edition
2021 page 23.
Working with our Memory.
An Overview
According
to Goldberg the mechanism to enable enjoyment of our enhanced understanding is
in the architecture of our frontal lobes which facilitate our short term
working memory. That allows us to retrieve information stored in the depository
and older ‘limbic’ areas of the brain for dynamic processing in the frontal lobes
area which enables our self-awareness.
Elkhonon
Goldberg ‘The Executive Brain- Frontal Lobes and the Civilized Mind -pages
77.79.
Short term memory
Due to
the dynamic nature of the frontal lobes of the brain which facilitates our
state of awareness not a great deal of information can be resident at any given
time. Even so it’s quickly going to fade away, except for a few rare
experiences that then form in the long term memory. Rehearsing what you're
going to say for instance when you have to make a speech can help you memorise
those points. Similarly, grouping them together can boost your memory capacity.
But as anyone who has given a speech a few years earlier knows one can scarcely
recall the all the details unless it is associated with some very significant
place or was at a time of heightened emotions.
But not only does our working memory provide a rapid problem solving function, it also resolves issues or actions as in daily living which are all reliant on memory. The information to hand in assisting those executive styled decisions or mundane matters are stored in other depositories but referenced via the neuronal network to the working memory. For instance as I type out these notes on my computer keyboard my short term memory keeps track of the sentences. Similarly, should I stop and decide to go shopping, it will determine a route and so the list goes on i.e. the voice in your head storing the audio data and our mind's eye that provides the images and mental maps. This is also the episodic buffer for information flowing from the senses and allows us to keep track of time. The Science of Memory-2021 2nd edition - Types of Memory – Short Term Memory page 31
To reiterate the extent to which we can create new memories in the long term memory repositories from these interactions in the short term memory depend to a large degree on repetition and the extent of emotional attachment.
Forming long Term Memories
Repetition
of active connections cement these memories whereas those that aren’t used can
disappear entirely, as previously explained.
The
networks of brain cells that store long term memories are called ensembles and
are linked to the groups of neurons that became active to create those
memories. https://qbi.uq.edu.
How you access those networks is by accessing the traces left from your prior experiences which are remembered. However there exists some debate as to the veracity of this popular view within the science of memory.
The
problem with this idea from a philosophical perspective is it is hard to imagine how all of this works
in practice in a convincing narrative. That is what is the relationship between
traces, which are never strictly identical to those representations after
retrieval and how in turn does the link inform our perceptual experience.
On the other hand, what we might be able to say with some assurance is it (memory creation and reconstruction) involves physical changes in neurons that enhance altered levels of electrical and chemical communication. If that all sounds rather vague that’ s because how this precisely is achieved as a memory is not known, or at least to the extent it can’t be rationally outlined, leads one to confirm it remains a mystery.
This view
is argued strenuously by Prof. Raymond Tallis 2017 in his book Time and
Lamentation: Reflections on Transience. Extracts were published in Philosophy
Now under the heading: The Elusiveness of Memory.
Different Types of Memory - Episodic, Semantic and Procedural.
Episodic
These memories involve remembering an episode or past experience, inclusive of such mundane things as what you had for tea last night or what to include in a memoir.
Memoirs
According
to Dr John Stuyfbergen, who is well qualified in autobiography, fictitious
inclusions or interpretations fill in the minor details for both reader and
writer.
Writing your memoir and interpretation of those memories.
You may
remember accurately and precisely the items etc. in your lounge room when you
were young. That would be an interesting fact. But someone who doesn’t know
precisely and accurately would have to write some facts and some fictional
accounts. And that is more interesting, because the reader may ask himself why
does the author remember (fictionalised or not) - those particular items. How
can we interpret that? Does he (fictionally or factually) remember particularly
feminine items or masculine items, small things or big things, items which
become important later in his memoir?
On the other hand Semantic memories store logical and knowledgeable aspects plus facts and procedural is involved in muscle memory tied to links to the senses.
A good way to explain all of these different types is as follows:
An
example is when I entered the Great Victorian Bike Ride.
Although
I hadn’t ridden a bike for over 30 years prior to entering, my procedural
memory meant I didn’t have to learn how to ride the bike again. Procedural
memories are where our bodies remember how to coordinate the different limbs
and perceptions based on previous attempts at bike riding.
But as my
old bike didn’t have prior gears my semantic memory of how to use those gears
on the new bike i purchased was absent. Observing how the gear switched the
wheel rotation circumference and using the gears then became part of my
semantic memory. But I also vividly recall in my episodic memory learning how
to ride with my father as a child. I see the picture of that early experience
just as I type out this sentence almost as clearly as it was then. No doubt my
memory was greatly enhanced as it was such an emotionally charged exciting
experience when my father let go of the bike and I peddled off on my own,
feeling as free as bird. But I am not going to recall other memories anywhere
near as well as there isn’t that strong emotive attachment. That’s the
problem in testimony as the mind decides what’s important according to
emotional attachment. Ask me something else about an incident or even holiday
around the same time and the details may be nowhere near as clear.
Furthermore memories may be inadvertently or intentionally distorted or manipulated in adulthood.
Loftus
maintains research is beginning to give us an understanding of how false
memories of complete, emotional and self-participatory experiences are created
in adults. First, there are social demands on individuals to remember; for
instance, researchers exert some pressure on participants in a study to come up
with memories.
Second,
memory construction by imagining events can be explicitly encouraged when
people are having trouble remembering.
And,
finally, individuals can be encouraged not to think about whether their
constructions are real or not.
Creation of false memories is most likely to occur when these external factors are present, whether in an experimental setting, in a therapeutic setting or during everyday activities.
False memories are constructed by combining actual memories with the content of suggestions received from others. During the process, individuals may forget the source of the information. This is a classic example of source confusion, in which the content and the source become dissociated.
Elizabeth Loftus is an American cognitive psychologist and expert on human memory. Misinformation effect and eyewitness memory.
http://www.uky.edu/~bdabra2/HowFalseMemoriesFormLoftus.htm
DNA Testing
Fortunately, given the
advent of DNA dating back to the 1980s, forensic science can now provide proven
accuracy concerning the true identity of the perpetrators and has resulted in
uncovering
Instances
of innocent people being falsely accused.
The
statistics in the USA in this respect aren't encouraging with a large
number of individuals convicted through eyewitness misidentification to
have served an average of 14 years in prison before gaining exoneration.
Summing up on the
reliability of memory and the possibility of false memories.
From the
forgoing one can ascertain the formation and retention of memory is a
highly complex function that can be influenced by any number of social
constructs and exasperated by personal psychological deficiencies. It
In fact
the two are linked but give differing results, so that the emotional
impact whilst securing the memory might equally mean there are unintended
distortions in recollections in later life.
In a more general sense one might think of our memories as artist’s impressions rather than a videotape of a particular event.
To
reiterate memory recall is about tracers that act to enable one to recall and
reconstruct memories from the depositories in the vast network of our modern
day brains. As was argued previously as we can't say for sure how precisely
this is achieved so too we need to exercise care on forming firm judgments
relating to the truthfulness of memory. This is particularly relevant regarding
facts concerning memory as it applies to eyewitness accounts.
Conclusion
From my
limited research and in understand how memories are formed and retained I
believe too much reliance (in the absence of other factors such as DNA) is
placed on memory and eyewitness accounts which continues to be the case. Of course
there are expert witnesses and cross examinations that hopefully ensure there
aren't too many false convictions, but the few papers I have reviewed
aren't very encouraging.
So much
for the idea we can rely exclusively on memory in criminal prosecutions or
eyewitness testimony.
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