Biopsychology: topic 1 ‘divisions of the nervous system’

Question 1

what is the nervous system? what does it do? why does it do this?

Answer 1

• a complex system of nerve cells
• carry messages to and from the brain and spinal cord to different parts of the body
• helps all parts of the body to communicate with each other

Question 2

what is the nervous system sub-divided into?

Answer 2

• central nervous system (CNS) and peripheral nervous system (PNS)

Question 3

what is the role of the CNS?

Answer 3

• controls behaviour and regulates the body’s physiological processes made up of the brain and spinal cord

Question 4

what is the role of the PNS? how does it do this?

Answer 4

• transmits messages via millions of neurons (nerve cells) to and from the CNS
• relays nerve impulses from the CNS (the brain and spinal cord) to the rest of the body and from the body back to the CNS

Question 5

what is the PNS sub-divided into?

Answer 5

• somatic nervous system (SNS) and automatic nervous system (ANS)

Question 6

what is the role of the SNS? how does it do this?

Answer 6

• controls voluntary actions (skeletal muscle movement) by receiving information from the senses
• carries sensory and motor information to and from the CNS

Question 7

what is the role of the ANS? how does it do this?

Answer 7

• governs vital functions in the body such as breathing, heart rate, digestion, sexual arousal and stress responses
• controls involuntary actions such as breathing, heart rate, digestion via internal organs and glands in the body
• carries only motor information to and from the CNS

Question 8

what is the ANS sub-divided into?

Answer 8

• the sympathetic nervous system and the parasympathetic nervous system

Question 9

what is the role of the sympathetic nervous system? how does it do this?

Answer 9

• primarily involved in responses that help us deal with emergencies (eg fight or flight response)
• neurons travel to virtually every organ and gland within the body, preparing the body for rapid action
• inhibits bodily processes such as digestion and saliva production)

Question 10

what is the role of the parasympathetic nervous system? how does it do this?

Answer 10

• primarily involved in returning the body to a rest state once the emergency has passed (rest and digest)
• bodily processes that are inhibited by the sympathetic branch are returned to normal

Question 11

what is the role of the brain?

Answer 11

• involved in psychological processes and is the centre of all conscious awareness
• the brains outer layer (the cerebral cortex) is highly developed in humans and is what distinguishes our higher mental functions from those of animals

Question 12

what is the role of the spinal cord?

Answer 12

• the spinal cord is an extension of the brain
• it is responsible for reflex actions such as pulling your hand away from a hot plate
• also responsible for relaying information between the brain and the rest of the body