This week’s lecture was about synapses and synaptic transmissions and how a signal transmits from one neuron to another. We learned about chemical synapses and the way the action potential opens the channels in the axon terminals and allows the vesicles to release neurotransmitters to the synaptic cleft. There are three main categories for neurotransmitters: amino acids, amine, and peptides, each has particular characteristics and can release under specific circumstances at synapses (e.g., some have very high transmission speed and others are slower). I had been familiar with some of these neurotransmitters like dopamine or serotonin before this lecture but during pre-reading and lecture I understood their functionality in the brain.
A special interesting part of this lecture was about inhibitory and excitatory synapses and neurons. It was very interesting to know that depending on the transmitter and receptor of the postsynaptic membrane, released neurotransmitters at synapses cleft can either excite or inhibit the postsynaptic action potential (EPSP or IPSP). For instance, gamma-aminobutyric acid (GABA) is always released at presynaptic terminals to provide inhibition and then binds to GABA-A or GABA-B receptors. I research functional inhibition and activation in the brain and this part helped me to better understand these mechanisms.
Generally, the coursebook is very interesting although there are a lot of details to remember.