- LECTURE 3 -
BRAIN STRUCTURE & FUNCTION
NB: this section is where 20 marks of short answer questions in the exam will come
from. THIS IS A VERY IMPORTANT SECTION!
WHY IT'S IMPORTANT TO UNDERSTAND THE BRAIN’S STRUCTURES AND
FUNCTIONS
1. The brain can be divided into distinct parts, each with their own function
2. Brain behaviour relations: if we know a specific part of the brain performs
specific functions, and if it is damaged, we can predict what kind of functions
will be impaired afterwards
a. We can also predict what will be intact and what we can rely on to
compensate for the functions lost
b. EG: if you start forgetting things, you will counteract this by making
schedules, setting reminders etc… Essentially, you begin counteracting
your forgetfulness with your ability to plan ahead and schedule
things.
PROTECTION OF THE CENTRAL NERVOUS SYSTEM
1. Skull and spinal column
2. Meninges
3. Ventricles
1. THE SKULL & SPINAL COLUMN
The skull is a bony encasement that protects and encases the brain
2. Made of interlocking cranial plated
a. When born, you have fontanelles, which are unfused cranial plates
b. This is because newborn babies’ brains are much smaller than they
will be as adults1, and there is a lot of brain growth in the first year
of life
1
Newborn babies' brains are 25% the size of adult brains. Within the first year of life, the baby’s brain
expands by 75%
, c. If there was a rigid, fused skull in the baby, this massive expansion of
the brain in the first year of life could not take place, hence the
presence of fontanelles
d. After 2 years of life, the cranial plates begin to infuse
The spinal column is the bony encasement of the spinal cord
- The spinal column consists of vertebrae that protect the spinal cord from
external damage
2. THE MENINGES
The meninges are 3 layered semi-permeable membranes that fit on the outside
of the brain
- They are underneath the skull and above the brain
- Play a big role in protecting the brain
- Are not involved in cognition whatsoever
STRUCTURE:
Under the skin and skull:
1. Dura mater (or Dura)
a. Thickest, toughest layer
b. The outermost layer offers the most protection from internal damage
2. Arachnoid mater (or Arachnoid)
a. Has a spider web-like structure
3. Pia mater (or Pia)
a. Thinnest layer
BRAIN STRUCTURE & FUNCTION
NB: this section is where 20 marks of short answer questions in the exam will come
from. THIS IS A VERY IMPORTANT SECTION!
WHY IT'S IMPORTANT TO UNDERSTAND THE BRAIN’S STRUCTURES AND
FUNCTIONS
1. The brain can be divided into distinct parts, each with their own function
2. Brain behaviour relations: if we know a specific part of the brain performs
specific functions, and if it is damaged, we can predict what kind of functions
will be impaired afterwards
a. We can also predict what will be intact and what we can rely on to
compensate for the functions lost
b. EG: if you start forgetting things, you will counteract this by making
schedules, setting reminders etc… Essentially, you begin counteracting
your forgetfulness with your ability to plan ahead and schedule
things.
PROTECTION OF THE CENTRAL NERVOUS SYSTEM
1. Skull and spinal column
2. Meninges
3. Ventricles
1. THE SKULL & SPINAL COLUMN
The skull is a bony encasement that protects and encases the brain
2. Made of interlocking cranial plated
a. When born, you have fontanelles, which are unfused cranial plates
b. This is because newborn babies’ brains are much smaller than they
will be as adults1, and there is a lot of brain growth in the first year
of life
1
Newborn babies' brains are 25% the size of adult brains. Within the first year of life, the baby’s brain
expands by 75%
, c. If there was a rigid, fused skull in the baby, this massive expansion of
the brain in the first year of life could not take place, hence the
presence of fontanelles
d. After 2 years of life, the cranial plates begin to infuse
The spinal column is the bony encasement of the spinal cord
- The spinal column consists of vertebrae that protect the spinal cord from
external damage
2. THE MENINGES
The meninges are 3 layered semi-permeable membranes that fit on the outside
of the brain
- They are underneath the skull and above the brain
- Play a big role in protecting the brain
- Are not involved in cognition whatsoever
STRUCTURE:
Under the skin and skull:
1. Dura mater (or Dura)
a. Thickest, toughest layer
b. The outermost layer offers the most protection from internal damage
2. Arachnoid mater (or Arachnoid)
a. Has a spider web-like structure
3. Pia mater (or Pia)
a. Thinnest layer
