Anatomy and Physiology I Brain and Cranial Nerves fall 2017 (1).ppt

Anatomy and Physiology I –
Brain and Cranial Nerves
By learning you will teach; by teaching you will learn.
- Latin proverb

Encephalonic Divisions of the Brain
:
1) Telencephalon ( Cerebrum)
2) Diencephalon
A) Thalamus
B) Hypothalamus
C) Pituitary Gland
3) Metencephalon
A) Cerebellum
B) Pons
4) Mesencephalon (Midbrain)
5) Mylencephalon ( Medulla Oblongata)
A typical brain weighs about 3 pounds with male’s being about 10% larger than females in
size. However the brain size does not correlate to intelligence.
Anatomy and Physiology I –
Brain and Cranial Nerves
Objective 19

Anatomy and Physiology I –
Brain and Cranial Nerves
Objective 19
1) Cerebrum
-Largest section of the brain.
-Covered by “ Cerebral/neural cortex ”, which is a
superficial layer of gray matter.
- Cerebral Cortex – has (a) right cerebral hemisphere and
(b) left cerebral
hemisphere, which are separated by longitudinal fissure
but connected by “ corpus callosum ”.
-Each hemisphere receives sensory and sends motor
commands to opposite side of the body (no one knows why
the crossover exists).
- Two hemispheres have different functions, but different
regions in a hemisphere may have the same function.
A) Left Cerebral Hemisphere – reading, writing, math,
logic, and speaking are processed in this region.
B) Right Cerebral Hemisphere – emotions and recognizing
faces are processed is this region.
Larger number of “Artsy” people are left handed due to the
cross over.

Anatomy and Physiology I –
Brain and Cranial Nerves
Objective 11
-Lobes are divisions of the cerebral hemispheres that
are named after overlying skull bones . All lobes
integrate and process sensory information and
initiate motor commands .
4 Lobes :
a) Frontal Lobe – primary motor cortex ; voluntary
control of skeletal muscles ;
Pre Central Gyrus – (part of frontal lobe ) contains
the “ primary motor cortex ”.
b) Parietal Lobe – primary sensory cortex ;
perceives touch, pressure, pain, taste , and
temperature ;
Post Central Gyrus – (part of parietal lobe )
contains the “ primary sensory cortex ”.
c) Temporal Lobe – auditory and olfactory
cortex ; perceives hearing and smell .
d) Occipital Lobe – visual cortex ; perceives
visual stimuli .
e) Others (insula)-

Anatomy and Physiology I –
Brain and Cranial Nerves
Objective 19
2) Diencephalon
-Composed of:
(a) Thalamus- thought to be involved with
consciousness, levels of awareness and activity .
Damage can lead to permanent coma.
(b) Hypothalamus – located on floor of
diencephalon ; responsible for emotions and
hormone production .
- Infundibulum – a narrow stalk that
connects the hypothalamus to the pituitary
gland (brain to endocrine system).
(c) Pituitary gland- endocrine gland which
releases hormones to regulate homeostasis.

Anatomy and Physiology I –
Brain and Cranial Nerves
Objective 19
Cerebrum/Diencephalon/Mesencephalon
3) Mesencephalon
- Meso middle or mid brain .