Biopsychology
What makes you, you?
What makes you unique from
every other person?
The Mind is what the Brain does
• Specific areas of the brain and specific systems
in the body are responsible for
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Learning and Memory
Sensing and perceiving
Emotion
Personality
Planning
Attention and arousal
Motivation
Etc.
The building blocks of the
brain
The Neuron
The Neuron
• Types of Neurons
– Sensory neurons (carry messages from
sense receptors towards the CNS)
– Motor neurons (carry messages from
CNS toward muscles and glands)
– Interneurons (carry messages between
nerve cells)
The Structure of a Neuron
Neural Communication
• Two states
– Resting Potential
 Negatively charged ions on inside; positively
charged ions on outside; cell is negatively charged
on inside relative to outside
– Action Potential
 Based on summation of excitatory and inhibitory
signals
Cell depolarizes; i.e., cell becomes positively
charged
 Voltage change (electrical surge) travels down
axon and causes release of neurotransmitter into
the synapse
Neural Communication
• All or None Law
– Neurons either fire or they don’t
– Require a minimum amount of excitation or
stimulation in order to fire
– Once the minimum threshold has been
reached, the neuron will fire
– Regardless of the intensity of stimulation, the
neuron will fire with the same intensity
Neural Communication
• If neurons always fire with the same
intensity, how do we discriminate intensity
of the stimulus?
– The # of neurons stimulated by a single
stimulus
– Rate of firing (up to a maximum)
Neural Communication
• Once the neuron fires, it releases its
Neurotransmitter into the synapse
– Neurotransmitter  Chemical messengers that relay
neural messages across the synapse
• Neurotransmitter fits in receptor like a key fits in
a lock
• Neurotransmitter either excites or inhibits the
post-synaptic cell by binding to its receptors
Neuron
Demonstration
Neural Communication
• Methods to stop neural transmission
– Reuptake
– Degradation
– Presynaptic autoreceptors
Seven Important
Neurotransmitters
Dopamine
Serotonin
Norepinephrine
Acetylcholine
GABA
Glutamine
Endorphins
Normal Function:
Dopamine
Serotonin
Norepinephrine
Produces sensations of
pleasure and reward; used
by CNS neurons in
voluntary movement
Problems with Imbalance:
Acetylcholine
GABA
Glutamine
Endorphins
Schizophrenia, Parkinson’s
disease
Substances that Affect:
Cocaine, amphetamines,
Ritalin, alcohol
Normal Function:
Dopamine
Serotonin
Regulates sleep and
dreaming, mood, pain,
aggression, appetite and
sexual behavior
Norepinephrine
Problems with Imbalance:
Acetylcholine
GABA
Depression, certain anxiety
disorders, obsessivecompulsive disorder
Glutamine
Substances that Affect:
Endorphins
Prozac, hallucinogenics
(e.g. LSD)
Normal Function:
Dopamine
Serotonin
Norepinephrine
Controls heart rate, sleep,
sexual responsiveness,
stress, vigilance and
appetite
Problems with Imbalance:
Acetylcholine
GABA
Glutamine
Endorphins
High blood pressure,
depression
Substances that Affect:
Tricyclic antidepressants,
beta blockers
Dopamine
Normal Function:
Serotonin
Pleasurable sensations and
control of pain
Norepinephrine
Problems with Imbalance:
Acetylcholine
Lowered levels resulting
from opiate addiction
GABA
Glutamine
Endorphins
Substances that Affect:
Opiates: opium, heroin,
morphine, methadone
Plasticity
• Plasticity –
– Ability of the nervous system to adapt or
change as the result of experience;
sometimes helps the nervous system adapt to
physical damage
The Organization of the
Nervous System
Nervous system
Peripheral nervous
system
Autonomic
nervous system
Sympathetic
nervous system
Central nervous
system (CNS)
Somatic
nervous system
Parasympathetic
nervous system
Divisions of the Nervous System
• Central Nervous System (CNS)
– Brain and spinal cord
• Peripheral Nervous System (PNS)
– Connects brain and spinal cord with
the rest of the body
Peripheral Nervous System
• Somatic Nervous System
– Carries incoming messages from sense organs
– Carries outgoing messages to skeletal muscles;
mobilizes voluntary movements
• Autonomic Nervous System
– Carries signals from the CNS to the internal
organs
– regulates involuntary functions such as digestion,
respiration, heart rate
Autonomic Nervous System
• Sympathetic Division
– Mobilized under stress – (e.g., controls 4 F’s)
• Increases heart rate and respiration, increases
muscle tension, shuts off digestion
• Parasympathetic Division
– Responsible for basic processes or
homeostasis
• Slows heart rate and respiration, increases
digestive functioning
Example
• Hear rattlesnake
– Somatic NS  orients eyes to sound to locate
snake
– Sympathetic Division of ANS  mobilizes fight or
flight response (i.e., blood to skeletal muscles;
increases respiration)
– Somatic NS  initiates skeletal muscles to escape
– Once escaped, Parasympathetic NS initiates
relaxation response
The Endocrine System
(the body’s chemical messenger system)
The Endocrine System
• Pituitary gland
– Master gland; i.e., produces
hormones that influence the
secretions of all other endocrine
glands
– Attached to and controlled by
hypothalamus
The Endocrine System
• Endocrine glands release hormones into
bloodstream; circulate through body until target
organ is reached
• Non-stress conditions  supports
parasympathetic nervous system in maintaining
basic processes or homeostasis
• Stress conditions  supports sympathetic
nervous system through release of epinephrine
(adrenaline)
Example Revisited
• Hear rattlesnake
– Somatic NS  orients eyes to sound
– Sympathetic Division of ANS  mobilizes fight or
flight response
– Somatic NS  initiates skeletal muscles to escape
– Parasympathetic NS  initiates return to resting
state, But, …
– Endocrine system  release of adrenaline,
explains why you feel edgy for a long time
afterward
The Endocrine System
Glands
Systems/ Processes regulated
Anterior Pituitary
Ovaries and Testes, Milk production,
metabolism, stress reactions
Posterior Pituitary
Conservation of water, milk secretion, uterus
contractions
Thyroid
Metabolism, physical growth & development
Parathyroid
Calcium levels
Pancreas
Glucose (sugar) metabolism
Adrenal glands
Fight or flight response, metabolism, sexual
desire (especially women)
Ovaries
Female sex characs., production of eggs
Testes
Male sex characs., sperm production, sexual
desire
How Does the Brain
Produce Behavior and
Mental Processes?
The brain is composed of
many specialized modules
that work together to create
mind and behavior
Film on Structures of the Brain
Three Layers of the Brain
• Brain stem and cerebellum
– Drive vital functions, such as heart rate,
breathing, digestion
• Limbic system
– Adds emotions, complex motives, increased
memory abilities
• Cerebrum
– Enables reasoning, planning, creating,
problem solving
The Brain Stem and Cerebellum
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Thalamus
Pons
Cerebellum
Medulla
Brain stem
The Limbic System
• Hypothalamus –
Serves as the
brain’s bloodtesting
laboratory,
constantly
monitors blood to
determine the
condition of the
body
The Limbic System
• Amygdala –
Involved in
memory and
emotion,
particularly fear
and aggression
The Limbic System
• Hippocampus –
Involved in establishing
long-term memories
The Cerebrum
• Cerebrum –
Topmost layer of the brain; the
bulbous cap over the limbic system
• Cerebral cortex –
Thin gray-matter covering of the
cerebrum; carries on thinking and
perceiving
• Cerebral hemispheres –
The two walnut shaped halves of the
cerebrum, connected by the corpus
callosum
Phineas Gage
Specialization of the
Cerebral Hemispheres
Left Hemisphere
Right Hemisphere
• Spontaneous
speaking and
writing
• Responses to
complex commands
• Word recognition
• Memory for words
and numbers
• Sequences of
movements
• Feelings of anxiety
• Positive emotion
• Repetitive but not
spontaneous
speaking
• Responses to simple
commands
• Facial recognition
• Memory for shapes
and music
• Spatial interpretation
• Emotional
responsiveness
• Negative emotion
Film on Split-Brain