Stress can negatively impact memory through its effects on the hippocampus. The hippocampus is crucial for memory formation and highly susceptible to damage from prolonged stress. Studies have shown that long-term stress from conditions like PTSD, depression, and Cushing's disease is associated with hippocampal atrophy and memory impairment. A small study of undergraduate students found an inconclusive relationship between stress levels and short-term memory test performance, though a larger sample size may have yielded clearer results.
2. What is stress?
Stress is any condition that disturbs the
physiological or psychological homeostasis
of an organism
Two types of stress:
External stress is an external condition that puts
a strain on the homeostatic mechanisms of the
body
○ Example: excessive heat
Internal stress is when perceived demands
exceed perceived ability
○ Example: unrealistic expectations
3. Positive and Negative Stress
Positive Stress (Eustress) Negative Stress (Distress)
Stress is positive when it Hinders performance
is essential for survival or
aids performance
Chronic stress
The primal function of
stress is survival
Can cause physical
Motivation and/or mental damage
4. Seyle’s General Adaptation
Syndrome
Three stage process that explains how
individuals respond to stress
First Stage – Alarm Reaction
○ Psychological
○ The body has become aware of the stress and
prepares itself for the fight-or-flight response by
releasing the hormones adrenaline and
corticosteroid
○ Effects of the hormones include: increased heart
rate, breathing rate, blood sugar level, and
perspiration, and a decrease in digestion
○ Takes place in the Sympathetic System of the
Autonomic Nervous System
5. Seyle’s General Adaptation
Syndrome
Second Stage - Resistance Stage
○ The body attempts to cope with the stress
○ If the stress continues for a long period of
time, the body will attempt to remain alert to
be prepared to deal with the stressor
○ The body cannot continue in this stage for a
longed period of time because its resources
will gradually be depleted
○ Takes place in the Parasympathetic System of
the Autonomic Nervous System
6. Seyle’s General Adaptation
Syndrome
Third Stage - Exhaustion Stage
○ At this point, all of the body’s resources have
been depleted and the body is no longer able
to function normally
○ The symptoms that were caused in the alarm
stage such as increased heart rate, breathing
rate, blood sugar level, and perspiration, and
a decrease in digestion may reappear
○ If the body experiences a prolonged
exhaustion stage the immune system can be
impaired and severe long term damage can
result
7. Memory
Memory is an organism's ability to store,
retain, and recall information and
experiences.
There are many different models that
explain what memory is and how it
functions.
8. Information Processing
Perspective
There are three main stages in the
formation and retrieval of memory
First Stage – Encoding
○ Information is received, processed, and
combined with other received information
Second Stage – Storage
○ The creation of a permanent record of the
encoded information is formed
Third Stage – Retrieval
○ Stored information is recalled using a cue
9. Types of Memory
Three types of memory
Sensory Memory is memorization or the ability to
look at an object and remember what it looked like
○ Brief – lasts only 200 to 500 milliseconds after the item
is observed
Short-Term Memory can be recalled for several
seconds to even a minute after the information has
been observed
○ Capacity is limited
Long-Term Memory information from sensory
memory or short-term memory that has been
transferred to long-term memory through repetition
or other means
○ Unlimited in capacity and duration
10. Hippocampus and Memory
The portion of the brain most responsible for
memory is the hippocampus
Located in the medial temporal lobe of the
brain
Responsible for converting information in the
short-term memory into the long-term memory,
and inhibition and spatial perception
It is not yet known what exact role the
hippocampus plays in memory
11. The Effects of Stress on
Memory
Stress can affect various aspects of memory, brain
structures, and physiological processes
There have been many studies performed on both
rodents and humans of how stress affects the
hippocampus
The hippocampus, which is a crucial component of
memory, is highly susceptible to long-term stress
than other portions of the brain
Due to the hippocampus having a large quantity of
corticosteroid receptors
Stress hormones such as corticosteroid released over a
long period of time damages the hippocampus
12. The Effects of Stress on
Memory
The damage to the hippocampus can include:
reduced excitability of hippocampal neurons,
inhibited creation of new neurons, and atrophy of
dendrites
The result is that certain hippocampal functions such
as learning and memory are impaired and damaged
due to stress
Some of these effects can be reversed if the stress is
discontinued
Some of the effects are irreversible
13. Studies
Studies done over two decades support the correlation between stress,
the hippocampus, and memory impairment
Patients that suffer from Post-Traumatic Stress Disorder have
hippocampal atrophy
People diagnosed with depression and hypercortisolemia (a condition
where an individual has high amounts of circulating cortisol) have
memory impairments due to hippocampus damage
Patients that suffer from Cushing’s disease (a disease in which tumors
in the adrenal gland cause excess secretion of glucocorticoids) have
hippocampal atrophy and memory impairment
Studies conducted on rats that were exposed to stress or given
corticosterone displayed impairments in spatial memory
14. Our study
The objective of the study was to determine if there is a correlation
between stress level and memory performance.
Consisted of 11 participants, all over the age of 18, and current college
students
Participants were instructed to complete an Undergraduate Stress
Questionnaire to access their stress level
Participants were provided with a page that contained a series of
pictures and were asked to study them for 30 seconds
At the end of 30 seconds, the pages were collected, and the
participants were instructed to write down as many of the pictures that
they could recall onto the answer sheet
The hypothesis was that short-term memory performance of
undergraduates would decrease according to stress level.
15. Assessment
Stress levels were accessed by the
number of items the participant checked
on the Undergraduate Stress
Questionnaire
Memory test scores were accessed by
the number of correctly recalled pictures
16. Results
The results do not support nor reject the
hypothesis
Memory Test
16
14
Memory Test Score
12
10
8
6
4
2
0
0 10 20 30 40 50 60
Stress Level Score
17. Discussion
Although there is a slight downward trend in memory test
scores of the participants that had higher stress level scores
towards the end of the graph, the results are inconclusive.
It is predicted that with a larger sample of participants that the
hypothesis could be proven correct.
The study had many other variables that could have interfered
with the data.
The Undergraduate Stress Questionnaire did not take into account other
life stressors, therefore the participants stress levels could have been
inaccurately assessed
It is difficult to assess an individual’s stress level because the amount of
stress that a situation creates varies with each individual’s
perception, therefore the stress levels again could have been assessed
inaccurately
Participants were not screened for any learning or memory disabilities or
difficulties
18. References
Glassman, A. (2009). How stress affects short term and long
term memory. Journal of Professional Education, 12(5), 1-
16.
Kim, J. J. & Diamond, D. M. (2002). The stressed
hippocampus, synaptic plasticity and lost memories.
Nature Reviews Neuroscience, 3, 453-462.
Merz, C.J. & Wolf, O. T. (2010). Stress impairs retrieval of
socially relevant information. Behavioral
Neuroscience, 124(2), 288-293.
Stegeren, A.H. (2009). Imaging stress effects on memory: a
review of neuroimaging studies. The Canadian Journal of
Psychiatry, 54(1), 16-27.
Woods, D. D. & Baker, A. M. (2005). Memory models for
high-school psychology lesson plans. Psychology
Teachers Journal, 27(6), 35-52.