THE BIOLOGY OF MIND
Cognition
DO NOW:
Is the “brain” important in Psychology?
 How might brain functions shape our
personality?

BIOLOGY, BEHAVIOR, & MIND
Aristotle = Heart
To think, feel, and act
without a body is like…
Plato = Head
Biological Perspective::
The interplay of biology, behavior and the mind
NEURONS
Dendrite fibers [ Listen ]
Receive info & give it to cell body
= nerve cells
Action potential
Neurons
Axon fibers [ Speak ]
Send info to other neurons
Myelin Sheath
•Protective covering over axons
•Fatty tissue that insulates and
speeds impulse
•Grows up to about age25 – impacts
judgment, self-control, and neural
efficiency
•multiple sclerosis – loss of muscle
control
NEURAL COMMUNICATION
Synapse [ Lock & Key ]
•Release
Neurotransmitter
Binds to receptor site
•Reuptake extra
neurons by sending
neuron
Neurotransmitters impact:
•Hunger, Thirst, Emotions
•Don’t operate in isolation
•Acetylcholine (ACh)
•Opiate receptors
•Endorphins – natural
pain killers
Agonist : Amplifies normal sensations of
pleasure
Antagonist: Blocks a neurotransmitters
functioning – similar enough to fill receptor
site but not enough to stimulate it
NERVOUS SYSTEM
Nerves = Electrical Cables
•Link CNS to sensory receptors
The electro-chemical communication network
made up of all the nerve cells of the PNS & CNS
CNS (Central Nervous System)
•Brain & Spinal Cord
➨Sensory neuron carries
message to spinal cord
➨Motor neuron: carries
instructions to the muscle
➨Interneuron: Brain’s internal
network
More on CNS in a bit…
PNS (Peripheral Nervous System)
•Gathers info & Transmits
decision from the CNS
•Sensory & Motor System
➨Somatic N.S. - voluntary
➨Automatic N.S. – i.e. heartbeat
➨Sympathetic N.S. – alarms
➨Parasympathetic – conserves
•Keep body regulated
CENTRAL NERVOUS SYSTEM (CNS)
1. BRAIN
•Allows us to learn
•Strengthens connections between neurons
2. SPINAL CORD
•2 way highway between PNS & Brain
Motor info
Sensory Info
How can this be demonstrated?
3. ENDOCRINE system
•Hormones
•Very slow moving; lasts longer at times
•ANS orders adrenal glands to release epinephrine &
norepinephrine = increase in heart rate, bp, blood sugar
•Pituitary gland
•Controlled by hypothalamus
•Stimulates physical development
•Oxytocin (bonding), Cortisol (stress)
THE BRAIN
Cerebellum
Brainstem
Thalamus
Reticular
Formation
•Medulla
•Sensory
•Sorts
•Nonverbal
through
switchboard
learning
stimuli&
•Receives
•Relays
memory
• Heartbeat
info
alltosenses
other
&
(but smell)
areas
•Judges
Breathing
of time,
the brain
•Cross-over
monitors
•Directs
emotions,
point
info to
discriminates
•Body x Brain
medulla
&texture
and sound
cerebellum
Cerebral Cortex
•thin layer of interconnected neural cells
Motor Cortex
Parietal
Lobe –– Controls
Touch & body
voluntary
position
movement
Frontal Lobe
Sensory
Cortex
– Speaking,
– Processes
muscle
bodymovement,
touch and movement
making plans
sensations
& judgments
Occipital Lobe
Association
areas
– Receiving
– neuronsinfo
involved
from visual
in higher
fieldfunctioning
(eyes)
( speaking,
Temporal Lobethinking,
remembering,
– Auditory
learning,
info (ears)
etc.)
LIMBIC SYSTEM
Amygdala
• “Fight or Flight”
Hypothalus
•Hunger, Thirst, Temp
•Sends hormones
Hippocampus
•Memory
CASE STUDY: PHINEAS GAGE
BRAIN’S
PLASTICITY
Ability to modify itself after damage
• once neuron is destroyed
that’s it!
•BUT neural tissue can
reorganize itself
•What does that mean?
Corpus Collosum – band connecting
2 hemispheres
•Split Brain
•Left: Literal
•Rights: Infers, Speech,
Sense of self
Divided Brain