An introduction to the brain and nervous system

Question 1

Function of the brain

Answer 1

The command centre of the body!

Question 2

Hind Brain

Answer 2

-Medulla oblongata –tracts carrying nerves between rest of body and the brain
-Reticular formation –central core of brain stem, Contains nuclei.Plays role in arousal, sleep, attention, movement, muscle tone ,in maintenance of heart rate and breathing.
Pons – a bulge at the front of the brainstem
Cerebellum -is at the back of the brainstem, a large convoluted structure.Involved in sensorimotor control- damage means we cannot control movement and cognitive deficits too e.g. decision making and language.

Question 3

The Midbrain

Answer 3

• Top of the brain stem

- 2 Divisions-Tectum and the Tegmentum.

Question 4

The Midbrain-Tectum

Answer 4

-Has 4 bumps on the back of it
-Has Inferior colliculi and Superior colliculi.
Inferior =auditory function
Superior = visual function.
in humans, in lower vertebrates its all optical.

Question 5

The Mid brain-Tegmentum

Answer 5

• On the underside of the brainstem
• The tegmentum contains the Periaqueductal grey (PAG)
• PAG is the grey matter around the cerebral aqueduct that connects the 3rd and 4th ventricle.
• PAG has a role in pain reduction ,emotional responses and vocalisations.
• The Substantia nigra and the Red nuclei are important in motor co-ordination.

Question 6

Forebrain

Answer 6

Made of the Diencephalon and Telencephalon.

Question 7

Diencephalon

Answer 7

-Made up of the thalamus, the hypothalamus, optic chiasm, pituitary gland
-Sits above the midbrain and consists of two structures:
1)The Thalamus:
-Egg shaped structure
-contains many regions that “directs” fibres to the appropriate area of the cerebral cortex.
2)The hypothalamus:
– tiny region just under the thalamus
-Contains many areas involved in motivational behaviours (e.g. eating,sleeping ).
- It also exerts control over the pituitary gland and the autonomic nervous system.

Question 8

Telencephalon

Answer 8

Made up of:
Basal Ganglia 
Limbic System
Cerebral Commissures
Cerebral Cortex 
4 lobes (frontal, temporal, parietal, occipital)

Question 9

Structures that make up Basal Ganglia

Answer 9

-Caudate – tail-like, with putamen at the centre-these are striped in appearance and called
the striatum.
-Globus pallidus -appearance of a pale globe
-Pathway from the striatum to the Substantia nigra in mid brain is involved in voluntary motor responses.
-Deterioration of this pathway characterised by tremors,rigidity and lack of voluntary movement ,leads to Parkinson’s disease
Nucleus accumbens -involved
In the rewarding effects of addictive drugs- a dopamine rich region.

Question 10

The Limbic Cortex

Answer 10

• Below the cerebral cortex

- Involved in emotion and memory

Question 11

The Limbic System

Answer 11

-includes the cingulate cortex, mammillary bodies, the fornix, the septum hippocampus and amygdala.

Question 12

Amygdala

Answer 12

-Involved in emotion, in particular fear

Question 13

Hippocampus

Answer 13

• Only 3 layers of cells

- Has a role in memory particularly ,spatial memory

Question 14

The Cerebral Cortex

Answer 14

• Covers the cerebral hemispheres.
• Highly folded with gyri (ridges) ,fissures (large furrows) ,sulci (small furrows).
• Consists of 6 layers of cells.
• Outer surface (neocortex) consists of frontal, parietal, temporal and occipital lobes.

Question 15

Corpus Callosum

Answer 15

• Two cerebral hemispheres are joined by a band of fibres called the Corpus Callosum.
• Left hemisphere more involved in language
• Right in spatial and emotional processing.