Download Chapter 2 - Biological Basis of Behavior



chemicals released by
vesicles in sending
neuron
travel across the
synapse and bind to
receptor sites on
receiving neuron
2 TYPES =
EXCITATORY = stimulate the brain, increase the
likelihood that the neuron will fire an action potential
INHIBITORY = calm the brain, balance mood & are
depleted when excitatory are overactive
Neurotransmitters bind to the receptors of the
receiving neuron in a “key-lock mechanism”.

Serotonin
 various functions = body
temp., sleep, mood,
appetite, and pain
 Low levels =implicated
in depression & probs
with immune syst.
 High = Serotonin
Syndrome
 stimulant medications or
caffeine in your daily
regimen can cause a
depletion of serotonin


Norepinephrine (AKA
Noradreneline)

Prepares you for action

important for attentiveness,
emotions, sleeping, dreaming,
and learning

causes blood vessels to
contract & heart rate to
increase
GABA
 Gamma-Amino Butyric Acid
 An inhibitory
neurotransmitter
 “nature’s VALIUM-like
substance”
 Related probs = anxiety,
seizures, Huntington’s disease
 Valium and similar
antianxiety drugs work at
GABA synapses


Dopamine
 main focus neurotransmitter
 Affects neurons associated with
voluntary movement
 role in learning, memory, and emotions
 Loss of dopamine-producing cells =
Parkinson’s Disease
 Excess = focusing issues, less motivation,
schizophrenia
 Stimulants (ex: cocaine, meds for
ADD/ADHD, caffeine) cause dopamine
to be pushed into the synapse so that
focus is improved
 BUT cause a depletion over time
Acetylcholine
 triggers muscle contraction
 important role in arousal and attention
 Loss = linked to Alzheimer’s Disease

Endorphins
 linked to pain control and
to pleasure
 Reduce pain by inhibiting
or “turning down” neurons
that transmit pain
information
 natural, opiate-like
neurotransmitters
“morphine within”


 Dopamine pathways
are involved with
diseases such as
Parkinson’s disease
 caused by a
deterioration of brain
neuron’s that produce
dopamine (it is still
unknown why this
occurs)
Although not the sole cause of
schizophrenia, dopamine
unbalance is consistently
seen found in patients with
schizophrenia
Drugs that prevent dopamine
from binding to receptors
reduce the symptoms of
schizophrenia

Agonist


Increases production
Activates the neuron
receptor that it
attaches to

Antagonist


Decreases production
Deactivates the
neuron receptor that
it attaches to