Post on 08-Jan-2017
Biology Neurotransmitters
Pair-share
How do you think chemicals in our bodies impact our behavior?(Discuss with your table partner).
Nervous SystemQ: Why do psychologists study the brain and the
nervous system?
A: Some biological functions underly human behavior, and in order to form a fuller understanding of ourselves,
it’s important to recognize what aspects of our behavior we can attribute to our own bodies.
Psychologists who examine behavioral problems based on the ways in which our bodies affect our behavior are using the “biological” or “neuroscience” approach. Psychologists who specialize in studying the effects of biological functions on
behavior are called “behavioral neuroscientists.”
Nervous System
You have about 1 trillion nerve
cells in your body, and 100 chemicals that
transfer messages
between those nerves.
(Those chemicals are called
neurotransmitters).
Nerve Ending (outgoing)
Neurotransmitters
Neurotransmitters stimulate the nerve endings, or transmit electrical impulses from the brain to the body.
Nerve Ending (incoming)
Neurotransmitters(Chemicals that travel
between neurons)
(Axon)
(Dendrite)
Synapse (gap)
NeurotransmittersNeurotransmitter Name Function
Acetylchloline Movement control, thinking/comprehending
Glutamate Memory
Gamma-amino butyric acid (GABA) Eating, sleeping, aggression
Dopamine Movement control, attention, pleasure and reward feelings
Serotonin Eating, sleeping, mood, pain, depression,coping with stress
Endorphins Pain suppression, pleasurable feelings, appetite
NeurotransmittersAn excess or lack of neurotransmitters
can impact our behavior.
For example, Parkinson’s Disease causes the brain
cells that produce dopamine to die. The
lack of dopamine in the body leads to shaking,
irregular movements, and loss of motion control. Lack of dopamine also depresses your mood,
which affects your personality and habits.
NeurotransmittersAn excess or lack of neurotransmitters
can impact our behavior.
Dopamine is also associated with motivation and
reward. When we do things like eating,
exercise, and romancing,
dopamine is released in our brains.
Too much is also bad: studies show that unusually high amounts of dopamine in our bodies is related to schizophrenia.
Drugs & The BrainCertain drugs like cocaine cause a temporary
overproduction of dopamine, mimicking the reward sensation. In other words, cocaine gives you a greater feeling of reward than the things that naturally cause dopamine production. The result of this is addiction.
Dop
amin
e R
elea
se
Dop
amin
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Time Time
CocaineExercise, eating,
kissing/sex, winning
NeurotransmittersEndorphins block pain in your body, and are also
responsible for feelings of pleasure or happiness. A lack of endorphins may be responsible for certain forms of mental illness such as obsessive-compulsive disorder.
Endorphins are released when you exercise, and also when you experience pain.
Some people who engage in self-hurting behaviors may do so in part to feel the
feelings of euphoria prompted by controlled
amounts of self-inflicted pain.
NeurotransmittersAcetylcholine deficiency is an
abnormally low level of acetylcholine. This
neurotransmitter is involved in the control of muscle movement, learning, and memory formation. A lack of it causes uncontrolled muscle movements and difficulty forming and retrieving memories. Serotonin is a
neurotransmitter greatly involved in your mood. If you’re
feeling pessimistic, sad, distrustful, unconfident, or have panic attacks, you may have a
serotonin deficiency.
NeurotransmittersToday in modern medicine, drugs that stimulate
neurotransmitter production are being tested to see if they help relieve symptoms of clinical depression.
Symptoms of depression: Loss of interest Loss of appetite Loss of energyFeelings of lonelinessFeelings of worthlessnessAnger or irritabilityConcentration problemsReckless behavior
CausesWhat causes you to have too much or too little
of a neurotransmitter in your body?
Genetics: If family members have a chemical deficiency, it may
be passed on genetically.
Poor Nutrition:
Your diet impacts your bodily
chemicals (and obesity does too).
Stress: Stress can raise
or lower certain your
bodily chemicals.
Disease: Related to genetics:
Parkinson’s,Alzheimer’s,
and other diseases cause chemical
imbalances.
Drugs: Taking certain drugs confuses your body into
releasing chemicals when it has no
natural reason to.
Lack of Exercise:
Can cause problems like high blood pressure that
lowers blood-flow to your brain.
Alcohol, Smoking: Both cause
direct damage to the brain tissues.
Lack of Sleep:
Lowers blood flow to your
brain.
Brain Imaging
Brain ImagingTwo types of brain scans - PET scans and SPECT scans -
show how much activity is going on in the brain. “Activity” is measured by neurons firing, increased blood
flow, and/or release of brain chemicals.
This is a PET scan. After scanning thousands of
brains, researchers identified what “normal” levels of
brain activity looks like. If a brain shows activity higher
or lower than a normal brain, we know there is
something wrong.
Brain ImagingTwo types of brain scans - PET scans and SPECT scans -
show how much activity is going on in the brain. “Activity” is measured by neurons firing, increased blood
flow, and/or release of brain chemicals.
This is a SPECT scan. The healthy brain
will have a smoother shape with even brain activity. A brain with
problems will be shaped with holes or
lumps.
Brain ImagingTwo types of brain scans - PET scans and SPECT scans -
show how much activity is going on in the brain. “Activity” is measured by neurons firing, increased blood
flow, and/or release of brain chemicals.
For example, a SPECT scan can help us see if a
person’s brain is not producing enough of a
neurotransmitter, or is producing
too much.