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Biologische Psychologie III
Teil 2
Vorlesungsunterlagen, WS 2005/06 Univ. Prof. Dr.
Wolfgang Klimesch
Teil 2 Emotionen Grundbegriffe, Kortikale
Kontrolle von Emotionen, Furcht,
Angst, Freude, Motivation
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3. Psychophysiological and neural basis of
emotions 3.1 Behavior and emotions A taxonomy
3.2 Instincts
3.3 Basic Emotions
3.4 The generation of emotions Contribution of
subcortical and cortical regions
3.5 Cortical control of emotions.
3.6 Fear and anxiety 3.6.1 Fear
conditioning Experimental procedure and neural
pathway
3.6.2 The biochemical basis of fear and anxiety
3.6.3 The age of fear and anxiety
3.7 Reward, Joy and the dopaminergic system
3.7.1 What makes us happy?
3.7.2 Dopamin, Reward Exploratory Behavior
3.7.3 Dopamin and the catecholamines
Neural and chemical pathways
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3. Psychophysiological and neural basis of
emotions 3.1 Behavior and emotions A
taxonomy In psychology, there are many different
attempts for a taxonomy of different kinds of
emotions. The position, which is taken here, is
based on an evolutionary view. According to this
view, the basic questions to be asked are 1.)
what is the relevance of different types of
behavior for survival with respect to 1a)
individual survival and 1b) survival of a
species by reproduction, 2.) what is the
neurobiological basis of these behaviors. This
evolutionary view proceeds from the hypothesis
that 1.) emotions (urges, Triebe) are the
driving forces for life (i.e., for
survival and sex) and that 2.) in contrast to
cognitively guided behavior, emotions are
not learned but are genetically encoded. Note
that this does not mean that emotions may not be
modified by experience and learning to a large
extent.
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3. 2 Instincts are fixed action patterns (FAP)
which are triggered by a SIGN STIMULUS or
RELEASER.
As an example, a gull chick pecks at a long, thin
stick with a striped tip, a releaser of begging
behavior. For baby herring gulls the releaser of
begging behavior is a red dot at the end of the
bill. A red-winged blackbird copulates with a
model that consistens of a females tail raised
in the precopulatory display position. A greylag
goose rolls an egg back into the nest. The goose
will complete the retrieval behavior even if the
egg is taken away midway through the process.
Suggested reading Alcock, J. (1988). Animal
behavior, Sunderland, MA Sinauer Associates.
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5a
Wahrscheinlich gibt es auch beim Menschen
instinktives Verhalten.
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Was sind Emotionen ? Abgrenzung zu verwandten
Begriffen Gefühl, Trieb und Motivation. Trieb
strikte S-R Relation (FAP), fehlt in dieser Form
bei Emotion Motivation homöostatische Eigenheit
und kognitive Komponente, fehlen in dieser Form
bei Emotion. Gefühl wird weitgehend synonym mit
Emotion verwendet. Definitionsversuch Emotionen
sind REAKTIONSMUSTER Verhaltensentwürfe
(genetisch vorgegeben und durch Lernen
modifiziert) auf körperinterne oder körperexterne
Reize mit pos. oder neg. Valenz Traditionelle
Klassifikation Erleben von Emotionen angenehm
vs unangenehm Physiol. Reaktion aktivierend vs.
Desaktivierend Kommunikation der Emotion (Mimik,
Körperhaltung) Primäre Emotionen (defin.
Kriterium rasche, kurzanhaltende Reaktion),
Stimmungen sind lang anhaltende emotionale
Reaktionstendenzen. Glück, Freude (Lust) -
Furcht, Wut (Aggression, Angst) Überraschung -
Ekel
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3. 3 Basic Emotions
Anger, Happiness, Disgust, Surprise, Sadness, Fear
Figure 13.2 The six emotional facial expressions
Ekman and colleagues found to be universal across
cultures. See how well you can pick out the faces
showing anger, happiness, disgust, surprise,
sadness and fear. Adapted from Ekman (1973).
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Figure 13.3 Examples of positive and negative
emotional scenes form the International Affective
Picture System developed by Peter J.Lang and
colleagues (1995).
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3. 4 The generation of emotions Contribution of
subcortical and cortical regions
James-Lange Theorie Cannon Bard-Theorie
Stimulus z.B. Raubtier
Wahrnehmung, unbewußt
Cortex Emotion entsteht
Vegetativ (autonome) motorische Reaktion z.B.
Davonlaufen
Peripheres Feedback Arousal Herzklopfen, etc.
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Figure 13.4 MaxLean's limbic system. The
hippocampus was the centerpiece of the limbic
system, represented here by the seahorse, with
the black triangles representing the pyramidal
cells. It was believed to receive inputs from
external sensations as well as the internal and
visceral environment. The integration of these
internal and external inputs was believed to be
the basis for emotional experience. From MacLean
(1949).
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3. 5 Cortical control of emotions.
Figure 13.1 Phineas Gage's skull, and computer
reconstructions showing how the tamping iron
pased through his brain. The iron entered just
below the left eye and exited from the top. It
destroyed much of the medial region of the
prefrontal cortex.
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Orbitofrontal Cortex Lateral Ventro- medial
(a)
Function inhibit, evaluate and act on social
emotional information
(b)
Figure 13.5 (a) The human orbitofrontal cortex,
which is often divided into the ventromedial
prefrontal cortex (red) and the lateral
orbitofrontal cortex (green). (b) The human
amygdala is highlighted in red. From Davidson
et al. (2000).
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Figure 13.6 Our behavior re-flects the combined
influences of our personal desires and social
constraints. The driver is temp-ted to take the
car-pool lane to get home on time but is
restrained by her fear for the potential fine as
wall as the scorn of other drivers.
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Damage in ventro-medial region Imitation and
Utilization
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Figure 13.8 Patients with ventromedial cortical
damage fail to show autonomic, emotional
responses to arousing stimuli. Subjects were
shown a series of stimuli while measurements were
made of their skin conductance response (SCR), a
measure of emotional responsivity. Some of the
stimuli were affectively neutral (N) such as
photographs of the Iowa countryside. Others were
expected to evoke strong emotional responses (E).
The control subjects showed a large SCR to the
emotional stimuli, whereas the prefrontal lesion
patients had a "flat" SCR. Bottom panel is
adapted from Damasio (1994).
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Patient with prefrontal lesion
Figure 13.9 Emotional responses occur in reaction
to stimuli but also are useful in guiding our
decision processes. Subjects were required to
choose cards from one pile or the other, with
each card specifying an amount won or lost.
Through trial and error, the subjects could learn
that pile A was riskier than pile B. Control
subjects not only tended to avoid the high-risk
pile but also showed a large SCR when considering
choosing a card from this pile. The patients with
prefrontal lesions failed to show these
anticipatory SCRs. Interestingly, they did show a
large SCR upon turning over a card and
discovering they had lost 1000 (of play money).
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Figure 13.13 Example of the SCR in normal control
subject and patient S.P., who has amygdala
damage. The patient showed no response to the the
blue square (the conditioned stimulus, or CS),
indicating a lack of a conditioned response.
However, S.P. did respond to the shock (the
unconditioned stimulus, or US), indicating a
normal unconditioned response. The control
subject showed a response to both the conditioned
and the unconditioned stimulus. Even though S.P.
failed to show an indirect conditioned response
as measured by the SCR, she demonstrated intact
declarative knowledge of the fear conditioning
procedure. When shown the data and asked to
comment on her performance, S.P. replied, "I knew
that there was an anticipation that the blue
square, at some particular point in time, would
bring on
one of the volt shocks. But even though I knew
that, and I knew that from the very beginning,
except for the very first one where I was
surprised. That was my response - I knew it was
going to happen. I expected that it was going to
happen. So I learned from the very beginning that
it was going to happen blue and shock. And it
happened. I turned out to be right, it happened!"
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Figure 13.14 Two methods by which humans can
learn about the aversive properties of an event.
(a) Fear conditioning, in which the aversive
properties of the blue square are learned by the
pairing of the square and shock. (b) Instructed
fear, in which the blue square is linked to the
shock by verbal instruction. In both cases, the
amygdala plays a role in the expression of the
fear response.
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Happy Face
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Fearful Face
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Patient with amygdala damage
Figure 13.15 Exmaple of the deficit in
identifying and responding to fearful facial
expressions by a patient with amygdala damage
(blue person) compared ot a control subject
(green person).
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Figure 13.17 The neural pathways that control
voluntary and spontaneous facial expression are
different.
(b) The neural networks for spontaneous
expressions involve older brain circuits and
appear to be the same as those in chimpanzees.
(a) Voluntary expressions that can signal
intention have their own cortical networks in
humans.
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Figure 13.18
The patient suffered brain damage to the right
hemisphere the lesion interfered with voluntary
facial expression
Voluntary facial expression
Spontaneous facial expression
A Parkinson's disease patient with a typical
masked face. Since Parkinson's disease involves
the part of the brain that controls spontaneous
facial expression, the faces of these patients,
when told to smile, light up, since the other
pathway is still intact.
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3.6 Fear and anxiety 3.6.1 Fear conditioning
Experimental procedure and neural pathway
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Unconditioned Stimulus Unconditioned
Response (UCS) (UCR) painful stimulus freezing,
increase in heart rate and
blood pressure. As Conditioned Stimulus (CS)
almost any kind of more or less neutral stimulus
(e.g., a sound) may be used.
Pairing of UCS (painful stimulus) and CS
(sound) Conditioned Stimulus Conditioned
Response (CS) (CR)
freezing, increase in heart rate and
blood pressure in response
to the
sound stimulus
EMOTIONAL CONDITIONING If the UCS evokes emotions
and/or a strong vegetative response, a single
pairing of the UCS and CS can bring on the
conditioned response.
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UCS (foot shock) and CS are paired
neutral sound stimuls
FREEZING Heart rate and blood pressure goes up
Rat shows exploratory behavior
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Now, after the CS is presented, without the foot
shock, the rat exhibits FREEZING. Heart rate and
blood pressure goes up. The fear response is
established
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Lesioning the auditory cortex or hippocampus does
not eliminate the fear response. Lesioning the
Amygdala, however, does.
Further reading LeDoux, E. (1997). Emotion,
memory and the brain. SciAm, Special Issue, Vol.
7 (1), 68-75.
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3.6.2 The biochemical basis of fear and anxiety
Investigation of animal behavior shows
consistently that a mother with a young baby
registers alarm if another potentially
threatening animal is approaching. On the other
hand, a baby left alone, exhibits signs of fear
and anxiety Experiments with young rhesus
monkeys, about 2 months old (after Kalin, N. H.,
1997. The Neurobiology of fear. SciAm, Special
Issue, Vol. 7 (1), 76-83) Alone condition
Isolated in a cage, young rhesus monkeys emit
coo sounds to attract their mother. No eye
contact condition If a human appears the young
monkey freezes in an attempt to evade
discovery. Stare or eye contact condition If a
human appears and stares at the young monkey it
becomes aggressive and e.g., begins barking.
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Rhesus Monkey Registers Alarm as another monkey
approaches her baby. The mothers fear is
evident in her threat face The open mouth
and piercing stare serve to intimidate would-be
attackers and intruders.
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Cooing
Freezing
Barking
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Cooing
Freezing
Barking
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The application of different drugs shows typical
changes in behavior
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Tranquilizer increase inhibition and suppress
fear (anxiety)
BENZODIAZEPINE (BZ) or
(BDZ)
GABA e.g., Valium, Librium and other
tranquilizer BZ-Rezeptors operate in a
similar way as GABA-R, opening of
Cl- ion channels they support the opening of
in postsynaptic membrane Cl- ion
channels (BZ antagonists suppress the opening
of Cl- ion channels and increase fear)

Hyperpolarisation

Inhibition Suppression of fear
Thus, BZ and GABA suppress fear. The experience
of fear is mediated by excitatory pathways using
glutamate, norepinephrine and other transmitters.
Betablocker inhibit epinephrine (Adrenalin)
Receptors.
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3.6.3 The age of fear and anxiety
Journal of Personality and Social Psychology,
2000, Vol. 79 (6) 1007 - 1021
Study 1 college students, 170 samples
Study 2 schoolchildren, age 16, 99
samples Three theories - overall threat -
economic conditions - Social connectedness
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Study 1
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Anxiety scores for women are about a quarter of a
standard deviation higher than for men
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Study 2
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3.7 Reward, Joy and the dopaminergic
system About 45 years ago, Olds Milner (1956,
SciAm, Oct.) reported that rats with an elctrode
implanted into a certain region in the brain
would press a lever to stimulate itself. Since
that time self stimulation behavior was studied
studied extensively. It was shown that the
dopaminergic system plays a major role (for
another meanwhile classical work see e.g.,
Routtenberg, A. 1978, The reward system of the
brain. SciAm, Vol. 239 (5), Nov. 122-131).
Stimulation of the medial forebrain bundle
(fibers passing through the hypothalamus) give
rise to the highest rate of selfstimulation. If
an animal (rat or rhesus monkey) has the choice
between electric stimulation of the medial
forebrain bundle and food reward it chooses
selfstimulation up to the point of selfstarvation.
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Early research has shown that in the regions
marked by rectangles reliable self stimulation
can be observed in the rat brain.
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Nerve cells that secrete dopamine have their cell
bodies concentrated in the substantia nigra and
the ventral tegmentum. Their axons project
primarily to the caudate nucleus, the frontal
cortex and the entorhinal cortex. Nerve cells
that secrete norephinephrine have their cell
bodies localized primarily in the locus
coereleus. They project to the cerebellum, the
cerebral cortex and the hypothalamus. Both
sysetms overlap much of the area that gives rise
to self-stimulation behavior in rats.
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Ad 1)
Lesion of locus ceruleus
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Ad 3) Lesion of medial forebrain bundle
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Drugs that elevate catecholamine levels or mimic
the action of these transmitters facilitate self
stimulation. Drugs which lower the level of
catecholamines or make them less effective
depress self stimulation.
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3.7.1 What makes us happy?
Experiments about self stimulation lead us to
conclude that joy is directly mediated by
endogenous physiological processes and not by
external stimulation. If this conclusion is true
happiness should not depend, e.g., on wealth and
income (provided basic needs are satisfied).
Research on happiness supports this view. See
e.g. Myers, D. G. Diener, W. (1997).The pursuit
of happiness. SciAm, Special Issue, Vol. 7 (1),
40-15.
BASIC FINDINGS 1) Most people report to be
happy (The following data are based on very large
samples 1.1 Mill. people were asked in 1000
surveys) Which of these faces represents the
way you feel about your life as a whole?
2) Men and women are equally happy 3) Happiness
does not depend on age
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4) Happiness does not depend on income
4) Married people are hap-pier than never married
(regardless of men or women) 39 of married
people are happy as compared to 24 of never
married people (average for 1970-80). 5)
Religiously active people report greater happiness
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3.7.2 Dopamin, Reward Exploratory Behavior
What is the answer of people with extreme
behavior which may be categorized as
exploratory ? Mountaineers - BECAUSE ITS
THERE was once the motto of mountaineers. In the
Siren Song of Everest, (National Geography,
Sept. 1997, Vol. 192 (3), 124-135), the 1933
pioneer George, L. Mallory is quoted MY DARLING
THIS IS A THRILLING BUSINESS ALTOGETHER. ICANT
TELL YOU HOW IT POSSESS ME, AND WHAT A PROSPECT
IT IS. AND THE BEAUTIY OF IT ALL. The author of
this article emphasizes ....climbers keep
coming, not because Everest ist the point of
exploration, but BECAUSE IT IS THE PATH, THE
ULTIMATE ROUTE FOR AN INNER JOURNEY THAT LEADS
THEY HOPE TO SELF-DISCOVERY. - More recently,
for extreme climbers, reaching the summit isnt
as important as the SKILL and THRILL of scaling
vertical ice. THE DANGER FUELS THIS SPORT says
one climber and another says ONLY FROM THE
EXTREME OF COMFORT AND LEISURE DO WE RETURN
WILLINGLY TO ADVERSITY. (National Geography,
Dec. 1996, Vol. 190 (6), 82-95. Extreme
mountain bikers, crossing the Alaska Range (775
Miles, 1200 km) - After a foot injury, sore
legs, sprained wrists, aching backs, half a dozen
flat tires, one of the bikers says after arriving
at the destination You get into a special zone
when you ride a bike here. YOU SMILE, LOOK
AROUND, AND SAY, THIS IS IT! (National
Geography, May 1997, Vol. 191 (6), 118-131. -
A biker crossing Australia in a circular loop of
10.000 Miles (about 16.000 km) writes in a letter
to his friend .... What have I let myself in
for? ... I could have said BECAUSE ITS THERE
... but ther was yet another reason. After 11
years my relationship with my wife broke down and
I really needed ....to come to some decison.
......MAYBE I WOULD FIND SOME ANSWERS ON THE
ROAD. National Geography, Dec. 1997, Vol. 192
(6), 48-67. Aviation pioneer Amelia Earhart,
whom flying made her famous and disappearing (in
1937 after attempting to fly around the world as
first woman aviator) a legendary, said THE LOVE
OF FLYING IS THE LOVE OF BEAUTY. National
Geography, Jan. 1998, Vol. 193 (1),
112-135. Scientist Nina Kraus on the ICON VII
conference (July 1999) In truth there is beauty
and in beauty there is truth,
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3.7.3 Dopamin and the catecholamines Neural
and chemical pathways
Dopaminergic cell groups and pathways (after
Nieuwenhuys, 1985, p.15 ff.).
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Some basic functional aspects of catecholamines
(Dopamine, Norepinephrine, Epinephrine) Stimuli
that evoke the release of catecholamines
typically are- stress - exercise - low
temperature - anxiety and aggression (flight
fight behavior) - exciting and rewarding
experiences Catecholamines - increase heart rate
and blood pressure - lead to vasoconstriction -
increase glucose metabolism
Brain areas with high concentrations of
catecholamines are DOPAMIN Basal Ganglia,
substantia nigra, the medial forebrain bundle and
certain areas of the limbic system. (cf. Fig. 5
in Nieuwenhuys, 1985) NOREPINEPHRINE Regions in
the brainstem particularly in the pons and locus
ceruleus. EPINEPHRINE Cell groups in the lower
part of the brainstem (caudal rhombencephalon)
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Catecholamines are compounds that consist of a
catechol nucleus (a benzene ring, dt. Benzol
Ring, with two hydroxyl substituents) and an
amine group. Catecholamines are also termed
monoamine because they are bult of a single
aminoacid What is an aminoacid ? Any aminoacid
consists of an CARBOXY group (COOH), an AMINO
group (NH2), and a SIDECHAIN (or remaining part
R) that determines the large variety of different
kinds of aminoacids.
The chemical structure can be characterized as
following
Alberts, B., Bray, D., Johnson, A., Lewis, J.,
Raff, M., Roberts, K. Walter, P. (1998).
Lehrbuch der Molekularen Zellbiologie. Wiley-VCH,
Weinheim, ISBN 3-527-30101-1
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Synthesis of Catecholamines
Chemical structure Enzymes
Name of substance
H NH2 C C COOH H H
Chemical pathway for catecholamines (see e.g.,
Birbaumer, 1990, p. 235 or Nelson, 1995, p.
70-73). The catecholamines, Dopamin,
Norepinephrine (dt. Noradrenalin) and Epinephrine
(dt. Adrenalin), are derived by enzymatic steps
from the single amino acid tyrosin. Together with
serotonin and melatonin (which are derived from
tryptophan) they belong to the group of monoamine
hormones/transmitters. Note that the name of the
enzymes describes their function. As an example,
the enzyme Tyrosinhydroxylase indicates that a
hydroxylgroup (OH) is added to Tyrosin. The name
Dopa-Decarboxylase indicates that a carboxylgroup
(COOH) is removed from Dopa. L- stands for left
winding molecules and PNMT for Phenyläthanolamin-N
-Methyl-Transferase.
Phenylalanine
Phenylalanine hydroxylase
H NH2 C C COOH H H
Tyrosine
HO
Tyrosine hydroxylase
HO
H NH2 C C COOH H H
Dopa ( L-Dopa)
HO
Catechol nucleus
Dopa decarboxylase
HO
H H C C NH2 H H
Dopamin
HO
Dopamin beta hydroxylase
HO
H H C C NH2 OH H
Norepinephrine
HO
PNMT Phenylethanolamine-N-methyl transferase
HO
H H H C C N OH H
CH3
Epinephrine
HO
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Some basic functional aspects of
catecholamines Stimuli that evoke the release
of catecholamines typically are- stress -
exercise - low temperature - anxiety and
aggression (flight fight behavior) - exciting
and rewarding experiences Catecholamines -
increase heart rate and blood pressure - lead to
vasoconstriction - increase glucose metabolism
Brain areas with high concentrations of
catecholamines are DOPAMIN Basal Ganglia,
substantia nigra, the medial forebrain bundle and
certain areas of the limbic system. (cf. Fig. 5
in Nieuwenhuys, 1985) NOREPINEPHRINE Regions in
the brainstem particularly in the pons and locus
coeru leus. EPINEPHRINE Cell groups in the
lower part of the brainstem (caudal
rhombencephalon)