Lecture notes for Brain & Behaviour

Introduction to psychology

31/01/20 Brain and behaviour


The nervous system




How is the brain protected?
How can a ‘bowl full of jelly’ be protected?
 Skull and meninges
 Ventricular system
 Blood-brain barrier.

Meninges
 Dura mater (“hard mother”)
- Outermost, tough
 Arachnoid membrane (“spider”)
- Subarachnoid space; filled with cerebrospinal fluid CSF), cushions the brain
 Pia mater (“pious mother”)
- The layer of the meninges adjacent to the surface of the brain; thin and delicate.

Meningitis = inflammation of the meninges.

Ventricles
 “Little bellies”
- Four hollow interconnected spaces located in the brain
o Each produce cerebral spinal fluid.

, Enlarged ventricles in brain are located near hippocampus (memory) = Alzheimer’s.




Cerebrospinal fluid
 Clear fluid
- Replaced every 3-6 hours
 Found in:
- Ventricular system, subarachnoid space
 Why do we need it?
- Protection from shock
- Reduction of weight
- Carries hormones to other areas of the brain.

Hydrocephalus-
 “Water” on the brain
- Not water, CSF
 Too much fluid, puts pressure on brain tissue surrounding ventricles
 Occurs at birth (congenital) or acquired (e.g. Traumatic Brain Injury/ stroke).

Blood-brain barrier
 Limits passage between the bloodstream and brain
 How?
- Capillaries are tighter the in the periphery
- Only small molecules can pass.

Development of CNS
 Brain development (ontogeny)
 Neural tube
- A hollow tube, serves as the origin of the CNS.

Terminology