types of neurotransmitters

• excitatory neurotransmitters

  -trigger nerve impulses in receiving neuron

  -stimulate brain into action
• excitatory example

  -adrenaline / dopamine cause excitation of post-synaptic neuron

  -increasing positive charge & making more likely to fire
• inhibitory neurotransmitters

  -inhibit nerve impulses

  -to calm brain & balance mood
• inhibitory example

  -serotonin / GABA causes inhibition of post-synaptic neuron

  -neuron becoming negatively charged & less likely to fire
• -nerve cells can receive both at same time
• how to calculate likelihood of cell firing

  -adding excitatory & inhibitory synaptic input

  -excitatory more active = cell fires at high rate

  -inhibitory more active = cell fires at much lower rate, if at all