synaptic transmittion

• Neurones communicate with each other within groups known as neurone networks.
• Each neurone is separated from the next synapse.
• When electrical impulse reach end of neurone (presynaptic terminal) triggers the release of neurotransmitters from tiny sacs – synaptic vessels.
• Neurotransmitter are chemical that diffuse across the synapse to the next neuron in train.
• Once it crosses gap – taken up by post synaptic receptor site on dendrites and onto next neurone.
• Chemical messengers are converted into electrical messengers.
• Only one-way presynaptic neuron terminal -> postsynaptic terminal.
• Several dozen types of neuron transmitters detected in brain.
• Each neurotransmitter has a specific molecular structure that fits the postsynaptic receptor perfectly.
• Each has specific function.
• Neurotransmitter (serotonin) causes inhibition in receiving neuron – becomes negatively charged.
• Neurotransmitter (Adrenaline) causes excitation of the postsynaptic neuron by increasing positive charge – increasing firing of neuron.
• When a postsynaptic neuron fires is decided by the process of summation.
• Excitatory and inhibitory influence are summed – net effect on postsynaptic neuron is inhibitory it is less likely to fire.
• More inhibitory doesn’t fire.
• More excitatory fires.
• GABA – calming.
• Dopamine – pleasure.
• Glutamate – memory.