Three-pound organ of pinkish-gray tissue.
10 billion nerve cells.
Responsible for all mental functions.
Control center for movement, sleep, hunger,
thirst and virtually other vital activity
necessary to survival.
All human emotions, including love, hate,
fear, anger, elation and sadness.
Receives and interprets the countless signals
sent from our body and environment.
The Brain Before and at Birth
• Medulla, Cerebellum, and Cerebrum
• All clearly separated
6th month (middle)
• A dentlike fissure appears on the surface of
• Baby‘s brain contain 100 billion neurons
Anatomy and Composition of
• Refers to all structures lying between the cerebrum
and the spinal cord
• Diencephalon, Midbrain, Pons and Medulla
• Covered by three membranes called Meninges:
• Dura mater – outer one; tough and shiny
• Arachnoid layer – middle; encloses the brain
loosely and does not slip down into brain’s
convolutions, or ridges.
• Pia mater – inner; consists mainly of small blood
vessels that adhere to the surface of the brain.
THE BRAIN STEM
- Slab of white
- Outer layer
of gray matter
- 3 to 4 mm
- Insular lobe,
visible at the
- Lies in the
hind part of
- White fibers
- Three band of fibers
cerebellum to the other
parts of the brain.
- Superior (top) –
- Middle – pons
- Inferior (bottom) -
- Essential to
center for the
- Part of
- Consist of two
rounded mass of
gray tissue. (very
middle of the brain)
- Crucial relay station
for incoming sensory
signals and outgoing
motor signals (going
to and from cerebral
- Lies just below
the thalamus on
the midline base
of the brain.
- eating, drinking,
- Appears to act
- A transverse
and join its
- An intricate
Makes up o
portions of the
Linked together in
a unique way by
storage and recall.
Brain’s outer layer
of gray matter
3 to 4 mm. thick
It is composed of
which in turn cover
an inner mass of
• Somatomotor area – in front of central
fissure; responsible for nearly all
voluntary movements of the body
• Somatosensory area – behind the central
fissure; receives impulses from the skin
surface as well as from structures
beneath the skin; sensation such as
touch and taste are processed here.
• Frontal lobe
– Personality, behavior, emotions
– Judgment, planning, problem solving
– Speech: speaking and writing (Broca’s area)
– Body movement (motor strip)
– Intelligence, concentration, self awareness
• Parietal lobe
– Interprets language, words
– Sense of touch, pain, temperature (sensory strip)
– Interprets signals from vision, hearing, motor, sensory and memory
– Spatial and visual perception
• Occipital lobe
– Interprets vision (color, light, movement)
• Temporal lobe
– Understanding language (Wernicke’s area)
– Sequencing and organization
• Theories of neuroscientists on cellular
mechanisms by which nerve cells store memories
(Nash, 1998) :
– A change occurs in the ribonucleic acid (RNA) in the
cells of the cortex to code the memory trace in the
brain’s protein material.
– Peptides – (hormonlike substances) in the brain are
activated as an event is being stored as a memory.
– Neurotransmitters (chemicals that relay nerve
impulses between two or more neurons) are altered
as impulses stored.