BIOC32H3 Lecture Notes - Lecture 10: Temporal Lobe, Osmotic Concentration, Language Disorder
BIOC32
LECTURE 10
CNS Part II
Outline:
● Modulatory systems of the CNS
● Functions of the cerebral cortex
● Cerebral lateralisation
● Sensory integration
● Motor outputs
● Processing of visual and spoken language
● Emotion
● Sleep-awake state
Functions of different brain regions
●Cortex: understanding (cognition),
awareness, personality
●Diencephalon: hypothalamus, thalamus,
basal ganglia, pineal and pituitary gland
○ Hypothalamus controls
homeostasis and behaviour (e.g.
desire to eat and drink, sex drive,
body temp)
●Brain stem:
○ Medulla oblongata: arousal,
muscles, breathing, blood pressure
regulation, pain, swallowing,
vomiting
○ Viscera function is often integrated
in the spinal cord and brainstem
○ Viscera: organs, and related tissues
of the trunk
○ Pons: breathing, relays info
between cerebellum and medulla
●Cerebellum: coordination of fine movement,
balance, and equilibrium (together with inner
ear), body position and balance
Functional specializations of the cerebral cortex
1. Primary somatosensory cortex: receives
sensory input from skin, skeletal muscles,
touch, pain, itch, body position, viscera
2. Motor areas: directed at skeletal muscle
control
3. Association areas: integrate information from
motor and sensory areas: initiates voluntary
responses
4. Frontal lobe: coordinates information from
other association areas, forms personality,
perception, and awareness
The special senses
● Brain integrates and processes information
from the ears, eyes, mouth, nose
Auditory cortex
Receives information
from the ears (sound)
Visual cortex
Receives information
from the eyes (sight)
Olfactory cortex
Receives information
from receptors in the
nose (smell)
Gustatory cortex
Receives information
from the taste buds
(taste)
Lateralisation of the brain
BIOC32
LECTURE 10
● Each hemisphere of the brain controls
function on the opposite side of the body
(e.g. vision, skeletal muscles, hearing)
○ Left hemisphere controls right hand,
right hemisphere controls left hand
● There are also functional specialisation of
each hemisphere (cerebral dominance)
Left
Right
Interpretation of maths
and language
Spatial visualization and
analysis
Creative type, visual
type processes
Men more left brained
Women more right
brained
● The brain is plastic: following injury, skills
can be learned by the other hemisphere
Video: are you a left brain or a right brain thinker?
● Dancing lady
Emotion and Motivation: The Limbic System
● Emotions triggered in different brain regions
● Amygdala = centre for basic emotion -- for
survival
○ Stimulation causes fear, anxiety,
anger
○ Lesion decreases anger and
causes hypersexuality
○ Strongly linked with the
hippocampus to form “emotional
memories”
○ Also strongly linked with olfactory
bulb
■ Regulation to response to
fear (amygdala) is linked
with this because smell
can arouse the emotions,
fear, and memories that’s
linked with those situations
to help us avoid those
stressful situations
The amygdala hijack
● Video
● When one experiences an amygdala hijack,
the amygdala overtakes the neocortex (the
thinking part of the brain) and there’s little or
no ability to rely on intelligence or reasoning.
The effect is that energy is drawn exclusively
into the hijack. The immediate result of a
hijack is a decrease in working memory.
Adrenaline is released and will be present
and effective for 18 minutes, and other
hormones are released into the bloodstream
that will take 3-4 hours to clear
○ Cortex is no longer very functional
○ Can’t really remember anything
○ Can be applied to stressful
situations like exams
Document Summary
Diencephalon : hypothalamus, thalamus, basal ganglia, pineal and pituitary gland. Hypothalamus controls homeostasis and behaviour (e. g. desire to eat and drink, sex drive, body temp) Medulla oblongata: arousal, muscles, breathing, blood pressure regulation, pain, swallowing, vomiting. Viscera function is often integrated in the spinal cord and brainstem. Viscera: organs, and related tissues of the trunk. Pons: breathing, relays info between cerebellum and medulla. Cerebellum : coordination of fine movement, balance, and equilibrium (together with inner ear), body position and balance. Brain integrates and processes information from the ears, eyes, mouth, nose. Receives information from receptors in the nose (smell) Each hemisphere of the brain controls function on the opposite side of the body (e. g. vision, skeletal muscles, hearing) Left hemisphere controls right hand, right hemisphere controls left hand. There are also functional specialisation of each hemisphere (cerebral dominance) The brain is plastic: following injury, skills can be learned by the other hemisphere.
