Biopsychology - Brain scanning and bio rythms left too do Flashcards
What are the key facts about the nervous system?
- Is made up of billions of neurons
- The brain recieved sensory inputs from the bodys receptors mainly via the spinal cord
- The brain is connected to the muscles of the skeleton and controls internal organs
- It collects, proceses and responds to information from the enviroment
What are all the parts of the nervous systems?
- Central nervous systems
- Peripheral nervous system
- Autonomic nervous system
- Somatic nervous systems
- Parasympathetic division
- Sympathetic division
What is included in the central nervous system?
Brain and spinal cord
Whats included in the peripheral nervous system?
Cranial nerves and spinal nerves
Whats included in the autonomic nervous system?
Heart muscle, smooth muscle, glands
Whats included in the somatic nervous system?
Voluntary skeletal muscles
What does the parasympathetic division do?
- ‘Rest and digest’
- Slows the body down and reverses the effects of the sympathatic branch
What does the sympathetic division do?
- ‘Active and alert’
- Prepares the body for the survival response ‘fight or flight’
- Active during sports
How many major divisions in the nervous systems are there?
2
What are the 2 major divisions of the nervous systems?
- Central nervous system
- Periphral nervous system
What is the spinal cord responsible for?
Reflex actions such as movements and the reflex arc
What is the brain the centre of?
Conscious awareness
What are the 3 main parts of the brain?
- Cerebellum
- Cerebral cortex/cerebrum
- Brain stem, medulla
What is the outer layer of the cerebrum?
Cerebral cortex
How many lobes does the cerebral cortex have?
4
What are the 4 lobes of the cerebral cortex?
- Frontal lobe
- Parietal lobe
- Temporal lobe
- Occipital lobe
What is the function of the frontal lobe?
Motor movements, personality and deciision maker, Brocas area (production of speech)
What is the function of the temporal lobe?
- Proccessing auditory information
- Wernickes area (understanding language)
What is the function of the occipital lobe?
Proccessing visual information
What is the function of the parietal lobe?
Processes sensory information
Where are the 4 cortex’s in the brain?
- Motor cortex - frontal lobe
- Auditory cortex - temporal lobe
- Visual cortex - occipital lobe
- Somatosensory cortex - parietal lobe
What does the peripheral nervous system connect to?
Connects central nervous system to the rest of the body
What are the two parts of the peripheral nervous system?
- Somatic nervous system
- Autonomic nervous system
What is the key information about the somatic nervous system?
- Controls voluntary movement in the skeletal muscles
- Contains sensory neurons and motor neurons
- Sensory neurons transmit signals from the body to the brain
- Motor neurons transmit signals from the brain to the body
What is the key information about the autonomic nervous system?
- Regulates involuntary functions
- Recieves signals from sensory neurones to create involuntary responses in caradic and smooth muscles to regulate function such as heart rate and digestion
What are the two sub divisions of the autonomic nervous system?
- Sympathetic nervous system
- Parasympathetic nervous system
What is the sympathetic nervous system?
Controls our responses when we are in an emergency/threatening situation to provide rapid energy - ‘fight or flight’ response
What is the parasympathetic nervous system?
Returns our body to its normal resting state after an emergency has passed, refered to as ‘rest and digest’
What is the structure of neurons?
- Contails a cell body (soma) which contains a nucleus (stores genetic code)
- Dendrites branch our from the cell body and carry impulses to other neurons
- Axon projects away from the cell body and carries the signals recieved by the dendrites to other neurons
- Myelin sheath - a white fatty substance which insulates the axon and speeds the rate of conduction of signals
- Terminal - where a impulse can be transmitted to another neuron
What are the 3 types of neurons?
- Motor
- Relay
- Sensory
What is the structure of a motor neuron?
Short dendrites protrude directly from the cell body which is at one terminal, impulse carried away by long axon to another terminal
Where are motor neurons located?
Cell body is inside the Central nervous system
Axon is inside peripheral nervous system
What is the function of a motor neuron?
Controls muscles and organs (effectors)
What is the structure of a relay neuron?
Short dendrites carry impulse to cell body, impulse carried away to very short axon
What is the location of relay neurons?
Entire Neuron is inside central nervous system?
What is the function of relay neurons?
Allows motor and sensory neurons to communicate
What is the structure of a sensory neuron?
A long dendrite carries impulse to the cell body whic is at the side of a short axon (cell body has no dendrites itself)
Where is sensory neurons located?
Cell body is outside the central nervous system
Axon is inside the peripheral nervous system
What is the function of sensory neurons?
Carry nerve impulses
Describe the knee-jerk reflex
1) receptors on the skin (sense organ) detect the tap (stimulus)
2) Sensory neuron carries impulse to central nervous system
3) Impulse transmitted to relay neuron in central nervous system where sensation is proccesses
4) Impulse carried to the peripheral nervous system
5) Impulse transmitted to motor neuron
6) Receptors on muscles (effector) contract (response) - knee moves in response
What is synaptic transmission?
Refers to how neurons communicate with (transmit messages to) one another
What happens before action potential occurs in synaptic transmission?
The activated cell changes from its negative resting state to a positive activated state
What happens during synaptic transmission?
1) Action potential travels down the axon
2) Impulse travels down the axon on the pre-synaptic neurons, reaches the terminal buttons which triggers the release of neurotransmitters from the vesicles
3) Neurotransmitters diffuse through the synapse and bind to receptor sites on the post synaptic neurone
4) Stimulation off post synaptic receptors by neurotransmitters results in exicitation or inhibition of the post - summation
5) Leftover neurotransmitters is reuptake, broken down by enzymes or diffuses
What does the neurotransmitters contents at the synapse determine?
Whether the synapse is excitatory or inhibitory
What happens if the neurotransmitters is excitatory in synaptic transmission?
The post synaptic neuron is instructed to ‘fire’ (conduct a action potential)
What happens if the neurotransmitter is inhibitory in synaptic transmission?
The recieving neuron is instructed not to ‘fire’ (not to conduct action potential)
What happens when a post synaptic neuron recieves both inhibitory and excitatory inputs in synaptic tranmission?
It adds them together - where it fires or not depends on which is greater, this is known as summation
Describe excitatory neurotransmitters
- Are ‘on switches’
- Increase the likelehood that a signal is sent to the post synaptic neuron
- This is then more likely to fire as it becomes positively charged - called excitatory post synaptic potential (EPSP)
Name two examples of excitatory neurotransmitters?
- Dopamine
- Noradrenaline
Describe inhibitory neurotransmitters?
- Are ‘off switches’
- Decreases the likelehood that a signal is sent to the post synaptic neuron because it becomes more negatively charged
- This is called inhibitory post synaptic potential (IPSP)
Name two examples of inhibitory neurotransmitters
- GABA
- Serotonin
What does normal brain function and activity rely on?
A careful balance between excitatory and inhibitory functions
What can a imbalance of excitatory and inhibitory influences cause?
Neurological and mental disorders
What is the endocrine system?
- Works alongside the nervous system
- Is a network of glands within the body
What are glands?
- Secrete various hormones into the bloodstream, which then have an effect on organs that have cells with receptors for those hormones
What does glands effects on the organs influence?
Processes such as growth, metabolism and reproduction
Describe the pituitary gland?
- Known as the ‘master gland’
- Secretes hormones itself but also controls the activity of all other glands in the body
- Sits just below the hypothalamus and can be divided into anterior lobe (front) and posterior lobe (back)
What is the anterior lobe responsible for in the pituarity gland?
- Releasing the hormone ACTH
- This hormone stimulates the adrenal cortex to release cortisol during times of chronic stress to give us energy
What is the posterior lobe of the pituarity gland resposible for?
- Releasing the hormone ocytocin
- Responsible for producing contractions in the uterus during childbirth
What is the hormone associated with the thryoid gland?
Thyroxine