Module 2 1 1. What ultimately makes an axon send a signal (or not) to the terminal boutons? Explain the physical mechanisms that determine this action 2. Does myelination speed up or slow down the signal along the axon? Explain how it works. 3. Describe how EEGs and MRIs image the brain or record the activity of the working brain. What does an fMRI allow us to "see" that an EEG doesn't? 4 Choose four of the following neurotransmitters: acetylcholine, glutamate, GABA, dopamine, and serotonin. For each, provide their action on a post-synaptic neuron (excitatory or inhibitory), and the neurotransmitter's theoretical function. 5. Describe the difference between an agonist and antagonist, and provide a specific example of each.