Schizophrenia causes people to perceive reality inaccurately. The disease can cause hallucinations, delusions, and paranoia that distort how individuals perceive the world and other people. The structural abnormalities in the brain that may cause schizophrenia result in false or altered sensory information that does not align with actual external stimuli. This disconnect from reality is a core symptom of the disorder.
2. Absolute Threshold Difference Threshold
The weakest amount of a stimulus
you can detect.
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The smallest amount of change in
a stimulus you can detect.
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Review:
I can see a
candle flame
30 miles away!
(But not 31
miles away!)
I can see a difference
between these two
color hues:
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But not between these
two:
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3. Signal Detection Theory Sensory Adaptation
When multiple stimuli are
present, this is our ability to
recognize some signals, while
ignoring others.
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Our ability to become less
sensitive to an unchanging
stimulus over time.
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Review:
It’s a HIT! I
detected the
ring of my cell
phone, even
though there
are other
auditory
stimuli in the
room!
That construction next
door is so LOUD and
distracting!
Fifteen Minutes Later…
Oh! I forgot there was
construction going on outside.
I started to ignore it.
4. Top-Down Processing Bottom-Up Processing
Forming an understanding using
context and prior knowledge.
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Forming an understanding using
stimuli directly from the
environment.
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Review:
I’ve never driven a car or
seen an airplane cockpit
before: I don’t have any prior
knowledge or conceptual
understanding of the cockpit.
To form an understanding of
it, I need to observe each
part individually and push
buttons.
My dad used to fly me in his
airplane, so when I saw a
plane cockpit for the first
time, I used prior knowledge
to comprehend the layout. I
applied my understanding of
a car’s steering wheel to
understand the plane
steering wheel.
5. Pre-attentive Process Attentive Process
The unconscious process of
gathering information and forming
understanding.
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The active and conscious effort of
gathering information and forming
understanding.
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Review:
If you ask me which crayon is
missing in a box of crayons, I
can’t complete this task in
less that one second. I need
to actively process
information in my head first.
For example, I need to recall
what colors should be in the
box. Next, I need to evaluate
which colors are already
present.
I can spot the red crayon
in a box of crayons
pre-attentively. I can do
this task in less than one
second. I don’t need to
look at each crayon one
at a time in order to do
this task!
This is Slow!
6. Schizophrenia
A brain disease that may include delusions, loss of personality,
confusion, agitation, social withdrawal, psychosis, and bizarre
behavior. Individuals with schizophrenia may hear voices that are
not there. In extreme cases, they can have hallucinations. Some may
be convinced that others are reading their minds, controlling how
they think, or plotting against them.
Schizophrenics feel paranoid.
They feel like people are trying
to control them.They feel frantic,
and because of this, they might
become suicidal.
7. Schizophrenia
Scientists believe that when the human brain is forming in a
mother’s womb, the brain does not always develop properly: the
organization of brain cells and the connections between different
parts of the brain might have errors or structural damage. In rare
cases, even a tiny imperfection in the brain can cause someone to
perceive false information (like non-present voices).
Usually, schizophrenia develops
in young adults age 15-30. For
35% of people, symptoms
become progressively worse
over time. Others might have
only one schizophrenic episode
in their lifetime.
8. Schizophrenia
There is no cure for schizophrenia, but there are treatments
that can reduce the symptoms.
Treatments:
1. Join a support group and
communicate with trusted family
and friends.
2. Take antipsychotic medication to
reduce hallucinations, delusions,
paranoia, and disordered thinking.
3. Avoid alcohol and drugs. Some
evidence indicates a link between
drug use (especially marijuana)
and schizophrenia.These may
also interfere with your
medications.