The Biomedical Therapies

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Transcript The Biomedical Therapies

The Biomedical
Therapies
Therapies aimed at altering
body chemistry.
Drug Therapies
Antipsychotics, Anti-anxiety,
Antidepressants, and MoodStabilizing Medications
Drug Therapies
• With the advent of drugs, hospitalization in
mental institutions has rapidly declined.
• However, many patients are left homeless on
the streets due to their ill-preparedness to cope
independently out in society.
Psychopharmacology
• Psychopharmacology is the study of the effects of
drugs on mind and behavior.
• Psychopharmatherapy is the treatment of mental
disorders with medication…drug therapy.
• Drugs used to treat psychological disorders fall into 3
major categories:
– Antipsychotic
– Anti-anxiety
– Antidepressant
• (Mood stabilizers do not fit well into any of these
categories, but they are very important drugs in the
treatment of bipolar disorder.)
Testing New Drugs
• When a new drug is released, there is always
too much enthusiasm.
• New drugs must be tested using a double-blind
procedure to combat placebo and
experimental effects.
– Double blind – To test the effectiveness of a drug,
patients are tested with the drug and a placebo.
– Two groups of patients and medical health
professionals are unaware of who is taking the drug
and who is taking the placebo.
Antipsychotic Drugs
• Antipsychotic drugs (like Thorazine, Mellaril, and
Haldol) are used to gradually reduce psychotic
symptoms, including hyperactivity, mental
confusion, hallucinations, and delusions.
– Antipsychotic drugs appear to decrease activity at
dopamine synapses
– Sometimes producing unfortunate side-effects such
as symptoms of Parkinson’s disease and tardive
dyskinesia, an incurable neurological disorder
marked by involuntary writhing and tick-like
movements of the mouth, tongue, face, hands, or
feet.
Anti-Anxiety Drugs
• Antianxiety drugs depress
the central nervous system
and reduce anxiety,
apprehension, nervousness,
and tension by elevating the
levels of the Gammaaminobutyric acid (GABA)
neurotransmitter.
– Includes drugs like Valium,
Xanax, Buspar, Librium, and
Ativan
• Most widely abused drugs.
Antidepressant Drugs
• Antidepressants gradually elevate mood and
help bring people out of a depression. They
improve the mood by elevating levels of
serotonin
Figure 15.12: Antidepressant
drugs’ mechanisms of action.
The three types of antidepressant
drugs all increase activity at serotonin
synapses, which is probably the
principal basis for their therapeutic
effects. However, they increase
serotonin activity in different ways,
with different spillover effects
(Marangell et al. 1999). Tricyclics and
MAO inhibitors have effects at a
much greater variety of synapses,
which presumably explains why they
have more side effects. The more
recently developed SSRIs are more
specific in targeting serotonin
synapses.
Mood-Stabilizing Medications
• Lithium Carbonate, a common salt, has
been used to stabilize manic episodes in
bipolar disorders.
– It moderates the levels of norepinephrine and
glutamate neurotransmitters.
• It is very successful at preventing future
episodes of mania and depression, but it
can be toxic and requires careful
monitoring.
Brain Stimulation
Electroconvulsive Therapy and
Repetitive Transcranial Magnetic
Stimulation
Electroconvulsive Therapy (ECT)
• Electroconvulsive therapy
(ECT) is a biomedical treatment in
which electric shock is used to
produce a cortical seizure
accompanied by convulsions.
• ECT is used for severely
depressed patients who do not
respond to drugs.
• The patient is anesthetized and
given a muscle relaxant. Patients
usually get a 100 volt shock that
relieves them of depression.
– While the use of ECT peaked in the
‘40s and ‘50s, there has been a
recent resurgence in this therapy.
Video: http://www.youtube.com/watch?v=9L2-B-aluCE
http://www.youtube.com/watch?v=TvXlxW-JP6Y
Alternatives to ECT
Repetitive Transcranial
Magnetic Stimulation
(rTMS)
In rTMS, a pulsating
magnetic coil is placed
over prefrontal regions
of the brain to treat
depression with
minimal side effects.
Figure 15.8 Magnets for the mind
Myers: Psychology, Ninth Edition
Copyright © 2010 by Worth Publishers
Psychosurgery
Psychosurgery
• Psychosurgery was
popular even in
Neolithic times.
http://www.epub.org.br
• Although used
sparingly today, about
200 such operations
do take place in the
US alone.
Psychosurgery
• Surgery that removes or destroys
brain tissue in an effort to change
behavior.
• Antônio Egas Moniz (1874-1955) of
Portugal developed the lobotomy
(previously known as a prefrontal
leucotomy) in the 1930s. He was
also responsible for coining the term
psychosurgery.
• The procedure involved drilling holes
in the patient's head and destroying
tissue in the frontal lobes by injecting
alcohol.
• He later changed technique, using a
surgical instrument called a
leucotome that cut brain tissue by
rotating a retractable wire loop.
Advertisement for a
Leucotome in the 1940's
“The Lobotomist”
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Walter Freeman, and American neurologist and
psychiatrist, was inspired by Muniz’s work and
began performing his own lobotomies.
However, Freeman wanted to simplify the procedure
so that it could be carried out by psychiatrists in
mental asylums, which housed roughly 600,000
American inpatients at the time.
Roughly modeling the work of an Italian psychiatrist
(Amarro Fiamberti), Freeman decided to enter the
frontal lobes through the eye sockets instead of
through drilled holes in the skull.
In 1945, he took an icepick from his own kitchen and
began testing the idea on grapefruit and cadavers.
This new "transorbital" lobotomy involved lifting the
upper eyelid and placing the point of a thin surgical
instrument under the eyelid and against the top of
the eyesocket. A mallet was used to drive the
leucotome through the thin layer of bone and into
the brain. The leucotome was then swept from side
to side, thus severing the nerve fibers connecting
the frontal lobes to the thalamus. The leucotome
was then withdrawn and the procedure repeated on
the other side.
An early advertisement from the
American Journal of Psychiatry
promoting transorbital lobotomy.
Watch The Lobtomist, a documentary about Walter
Freeman and his procedures on PBS here:
http://www.pbs.org/wgbh/amex/lobotomist/program/.
(Watch “Production Line Lobotomies” and “Howard Dully’s
Story” in particular)
Rosemary Kennedy before she
was lobotomized by Freeman at
age 23. Her father sought the
lobotomy to cure what he called
“moodiness,” fits of irritability
and rebelliousness. He might
also have been afraid that she
might embarrass the family by
becoming pregnant out of
wedlock during one of her many
escapes from the convent
where she was being educated
and “cared for.” After the
lobotomy, Rosemary was
reduced to an infantile state and
needed constant care.
Psychosurgery
Psychosurgery is used today only as a last resort
in alleviating psychological disturbances.
Psychosurgery is irreversible. Removal of brain
tissue changes the mind.