Most prove to be as valuable to understanding

Most early experimental research on amnesia focused heavily
on patients with Korsakoff’s syndrome, amnesia caused by chronic alcoholism.
These studies did not prove to be as valuable to understanding memory as other
types of amnesia because it does not provide a direct assessment between damage
to the brain and long-term memory, due to the fact that memory impairment
experience by patients were gradual in decline, cause by a deficiency of the
vitamin thiamine, which is also known as vitamin B-1, rather than physical
trauma to the brain with immediate effect. The severe lack of thiamine, which
is responsible for maintaining the health of the nervous system (“Vitamins and
Minerals”, 2017), meant that the overall damage to the to the patient’s brain
was far more widespread, with further effects to the frontal lobe causing a
variety of cognitive deficits such as impaired risk assessment, decision making
and socially unacceptable behaviour (Society, 2018), which are not specific to
the memory systems.

   Patients who suffer
from Korsakoff’s syndrome can be more difficult to generalise into amnesia as a
whole due to the particular areas of the cortical damage, which in turn affects
the pattern of the memory impairment, varies wildly from patient to patient. In
addition to the imprecise region of impairment, patients usually, but not
always, experience Wernicke’s encephalopathy prior to Korsakoff’s syndrome
because of the thiamine deficiency, further affecting the variety in both
severity and extent of cortical damage. Research with Korsakoff’s syndrome, as
mentioned previously, does not provide a direct assessment of the impact of
cortical damage on long-term memory because patients can develop and learn a
multitude of compensatory strategies over time to alleviate symptoms of memory
impairment (Eysenck & Keane, 2015). To conclude this section, Korsakoff’s
syndrome does not relate directly to studies of amnesia and understanding of
memory as well as other studies have now made with patients with specific
injuries to the medial temporal lobes, but it does indicate and support the
idea that there is more than one long-term memory store due to the fact
patients do learn compensatory methods around their symptoms despite damage to
the brain.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

 

   HM, revealed to be
Henry Molaison after his death in 2008, is the most intensely studied example
of any amnesia to date. He received surgery to alleviate his epilepsy in 1953,
in which his medial temporal lobes, including his hippocampus, were removed to
stop seizures but resulted in him having his memory capabilities affected
dramatically, resulting in him suffering with anterograde amnesia. Corkin (1962
– 1997) reported many years later, HM did not know his own home address, the
identity of who cared for him on a daily basis, as he no longer could, the meal
he last ate or even recognise himself in a photograph taken at his fortieth birthday
in 1966. Mackay et al. (2011) reported that HM had difficulty with the use of
spoken language, the cortical damage inflicted by his surgery meaning he
struggled greatly with forming coherent sentences when speaking (McLeod, 2011).

   Research on HM and
his anterograde amnesia subsequently supports the notion between psychologists
that there is more than one long-term memory system, supported by the fact HM
retained the ability to perform specific actions pertaining to different types
of long-term memory, such as having a reasonable learning ability on a mirror
tracing task, drawing objects seen by reflection) and retained said learning
after a year from first undertaking the task (Corkin 1984). HM also sustained a
good attention span and an almost intact performance on tasks that involved
short-term memory systems, which indicated that there is a clear and distinct
difference between short-term memory and long-term memory, further suggesting
that it was his declarative memory that was impaired, not his non-declarative
memory (Eysenck & Keane, 2015). In summary, HM’s surgery indicates that the
medial temporal lobes, particularly the hippocampus, is heavily involved in
long-term memory systems, but that his overall good memory for events that
occurred a long time after his surgery suggests that memories are not stored
permanently within the hippocampus.

 

Paragraph 3 (Beth & Jon):-

   In 1997,
Vargha-Khadem et al. apparently obtained evidence of patients suffering from
amnesia that had very poor episodic memory but essentially intact semantic
memory, making the case of Beth and Jon unusual. Both children suffered
bilateral hippocampal damage with Beth developing brain damage at birth and Jon
at age four due to oxygen deprivation, meaning they both received cortical
damage before they developed semantic memory. Both patients experienced
extremely poor episodic memory for the activities they engaged with in the day,
yet both attended ordinary schools for their education with their semantic
memory in regards to their levels of speech, literacy, language development and
factual knowledge were within the normal range for their ages despite their
amnesia. However, subsequent research revealed that Jon did in fact have issues
with his semantic memory (Gardiner et al., 2008), which was made clear when Jon
was presented with facts about historical and geographical knowledge, revealing
that his rate of learning was drastically slower than healthy parameters.