Summation

• Once the receptors on post-synaptic neurones have been activates they either produce excitatory or inhibitory effects on the post-synaptic cell
• what does excitatory mean?


  increases the likelihood of a new action potential
• what happens during excitatory?


  depolarisation occurs- the additions of sodium ions which makes the cell more positive, this is known as exitatory post-synaptic potential (EPSP)
• what does EPSP stand for?


  excitatory post-synaptic potential
• when does inhibition occur?


  when stimulation results in increase of negative charge of neurones
• what occurs in inhibition?


  hyperpolarisarion and this is due to addition of negative potassium ions
• what does inhibition cause?


  decreases the likelihood of an action potential
• what is summation?


  the addition of + or - of post-synaptic potentials