central nervous system - brain Flashcards
What is the nervous system?
a large network of specialised cells known as neurones that act as the body’s communication system
what does the nervous system do?
receives and interprets internal and external information and sends reactionary responses which can be voluntary or involuntary
what is the nervous system responsible for? (6)
everything, including sensation, movement, organ function, learning and memory
What can the nervous system be broken down into? (2)
central nervous system
peripheral nervous system
What are the 3 basic functions of the nervous system?
- motor function
- sensory function
- Autonomic function
How does the nervous system help motor function?
it controls our body’s ability to carry out purposeful movements (eg picking something up)
How does the nervous system help sensory function?
it carries signals to the brain to help us touch, smell, see etc
How does the nervous system help with autonomic function?
by regulating certain body processes such a breathing that happens automatically
what are the three higher functions of the nervous system?
- cognition
- emotions
- consciousness
How does the nervous system help with cognition?
it relays information to the brain, making connections that affect the way you think, learn, move, and behave.
How does the nervous system help with emotions?
your emotions stimulate very specific activities in your nervous system
How does the nervous system help with consciousness?
we get our sense of being ‘alive’ and having awareness through our sensory experiences, the information from sensory experiences are relayed via the nervous system
what is the cycle of homeostasis in the central nervous system? (4)
- there is an imbalance that is detected by receptors
- input is sent via the afferent pathway to the control centre
- output is sent via the efferent pathway to the **effector **
- the imbalance is corrected
What are the 4 main functions of the brain?
- communication centre of nervous system
- it makes us human (rational thought, creativity etc)
- Interprets nerve stimuli and effects a response
- generates more sophisticated actions as the spinal cord can produce reflex actions
what are the 4 main bones of the skull?
frontal bone
parietal bone
temporal bone
occipital bone
what is meningitis caused by?
inflammation of the meninges
what is a subarachnoid haemorrhage?
When a blood vessel bursts in the subarachnoid space, one of the main two types of stroke
What is cerebrospinal fluid formed by?
the ventricles of the brain
How much blood does the brain receive every minute?
about 15% of the total blood pumped by our hearts to the body
What are the two main vessels that supply the brain with blood?
the internal carotid and vertebral arteries
What do the internal carotid and vertebral arteries form? where?
the circle of willis at the base of the brain
what is the circle of willis?
a ring of arteries located at the base of the brain
what is the main function of the circle of willis? (2)
to provide a collateral blood flow between the anterior and posterior arterial systems of the brain
and to alternate blood flow pathways between the right and left cerebral hemispheres
What is the circle of willis designed to protect?
to protect the brain from ischaemia (loss of blood flow) and stroke in the case of vascular obstruction or damage.