2. “If the human brain were so
simple that we could
understand it, we would be so
simple that we couldn’t”
-Emerson Pugh, The Biological Origin of Human
Values (1977)
3. Phineas Gage
• September 13th, 1848
• Phineas 25 years old
• Rutland & Burlington Railroad, Cavendish,
VT
• Paving the way for new RR tracks
• “Tamping Iron”
– 1.25in x 3ft
4.
5. • Accident
Phineas Gage
– Quick Recovery
• Months later: “No longer Gage”
– Before: capable, efficient, best foreman, well-balanced
mind
– After: extravagant, anti-social, liar, grossly profane
• Stint with P.T Barnum
• Died 12 years later
• Video Clip
7. The Brain
• Brainstem
–responsible for
automatic survival
functions
• Medulla
–controls heartbeat
and breathing
8. hippocampus
BRAINSTEM Heart
rate and breathing
CEREBELLUM
Coordination
and balance
Parts of the Brain
amygdala
pituitary
THALAMUS
Relays
messages
10. The Limbic System
• Hypothalamus, pituitary,
amygdala, and hippocampus
all deal with basic drives,
emotions, and memory
• Hypothalamus Hunger,
thirst, body temperature,
pleasure; regulates pituitary
gland (hormones)
• Pituitary “Master Gland”
– Stimulates other glands to
produce hormones
• Amygdala Aggression (fight)
and fear (flight)
• Hippocampus Memory
processing
11. The Limbic System
Hypothalamus
neural structure lying
below (hypo) the
thalamus; directs several
maintenance activities
Eating, drinking
body temperature
helps govern the
endocrine system via the
pituitary gland
linked to emotion
12. The Limbic System
Pituitary Gland
A pea-sized gland attached to the
hypothalamus by a thin stalk.
Has two bulb-like lobes
Secretes hormones that are used to control
other glands
GH – stimulates cells to grow & produce proteins
FSH – stimluates ovaries to produce eggs/testes to
produce sperm
Prolactin – stimulates mammary glands to produce
milk
13. The Limbic System
• Amygdala
two almond-shaped
neural
clusters that are
components of
the limbic system
and are linked to
emotion and fear
14. The Brain
• Thalamus
– the brain’s sensory
switchboard, located
on top of the
brainstem
– it directs messages to
the sensory receiving
areas in the cortex
and transmits replies
to the cerebellum and
medulla
15. The Cerebral Cortex
• Cerebral Cortex
–the body’s
ultimate control
and information
processing
center
17. The lobes of the cerebral hemispheres
Planning, decision
making speech
Sensory
Auditory
Vision
18. The Cerebral Cortex
• Frontal Lobes
– involved in speaking and
muscle movements and in
making plans and judgments
– the “executive”
• Parietal Lobes
– include the sensory cortex
19. The Cerebral Cortex
• Occipital Lobes
– include the visual areas, which
receive visual information from the
opposite visual field
• Temporal Lobes
– include the auditory areas, each of
which receives auditory information
primarily from the opposite ear
20. The Cerebral Cortex
• Frontal (Forehead to top) Motor Cortex
• Parietal (Top to rear) Sensory Cortex
• Occipital (Back) Visual Cortex
• Temporal (Above ears) Auditory Cortex
21. The Cerebral Cortex
Aphasia
impairment of language, usually caused by left
hemisphere damage either to Broca’s area
(impairing speaking) or to Wernicke’s area
(impairing understanding) –see clips
Broca’s Area
an area of the left frontal lobe that directs the
muscle movements involved in speech
Wernicke’s Area
an area of the left temporal lobe involved in
language comprehension and expression
22. Language Areas
• Broca
Expression
• Wernicke
Comprehension
and reception
• Aphasias
LEFT HEMISPHERE
24. Techniques to examine functions
of the brain
1. Remove part of
the brain & see
what effect it has
on behavior
2. Examine
humans who have
suffered brain
damage
28. Our Divided Brains
• Corpus collosum –
large bundle of
neural fibers
(myelinated axons,
or white matter)
connecting the two
hemispheres
29. Hemispheric Specialization
LEFT
Symbolic thinking
(Language)
Detail
Literal meaning
RIGHT
Spatial perception
Overall picture
Context,
metaphor
30. Contra-lateral
division of labor
• Right hemisphere
controls left side of
body and visual field
• Left hemisphere
controls right side of
body and visual field
31. Split Brain Patients
• Epileptic patients had corpus callosum cut
to reduce seizures in the brain
• Lives largely unaffected, seizures reduced
• Affected abilities related to naming objects
in the left visual field
33. Brain Plasticity
• The ability of the brain to
reorganize neural pathways
based on new experiences
• Persistent functional changes in
the brain represent new
knowledge
• Age dependent component
• Brain injuries
36. Sensation
• The process by which the central
nervous system receives input from
the environment via sensory neurons
• Bottom up processing
– Piece together information to build a more
complex system or a “bigger picture”
37. Perception
• The process by which the brain
interprets and organizes sensory
information
• Top-down processing
– Overview details more specific details
– “breaking it down”
38. The psychophysics of sensation
• Absolute threshold the minimum
stimulation needed to detect a stimulus with
50% accuracy
• Subliminal stimulation below the
absolute threshold for conscious awareness
–May affect behavior without conscious
awareness
• Sensory adaptation/habituation
diminished sensitivity to an unchanging
stimulus
39. The five major senses
• Vision – electromagnetic
– Occipital lobe
• Hearing – mechanical
– Temporal lobe
• Touch – mechanical
– Sensory cortex
• Taste – chemical
– Gustatory insular cortex
• Smell – chemical
– Olfactory bulb
– Orbitofrontal cortex
– Vomeronasal organ?
40. The sixth sense
And the seventh…and eighth…and ninth…
• Vestibular balance and motion
– Inner ear
• Proprioceptive relative position of body
parts
– Parietal lobe
• Temperature heat
– Thermoreceptors throughout the body, sensory cortex
• Nociception pain
– Nociceptors throughout the body, sensory cortex