A growing list...
'Mach bands' are a result of lateral inhibition, which is what the horizontal and amacrine cells do with the information provided by a photoreceptor in order to facilitate better edge perception.
'Parallel processing' is responsible for the possibility of a top down influence from higher order cognitive processes in the association cortex like past experiences to influence sensory perception.
'NMDA receptors' play a key role in a phenomena called long term potentiation by detecting coincidental firing of other neurons which results in the formation of long-term neural connections between neurons and consequently facilitates the storage of memory.
'Serotonin' plays a role in the inhibition of feeding such as reducing overall food intake and shifting preference away from highly palatable food when it is present in certain areas of the brain; which is supported by anecdotal evidence of the way psilocin evokes bizarre perceptual changes in the way the subject perceives their own interaction with food.
Practically speaking, 'habituation' is the opposite of 'sensitization', but technically speaking, the former is a short term result of neurotransmitter depletion resulting in a reduction of response after repeated stimulation, while the latter is result of long term anatomical changes in the synapse mediated by serotonin resulting in more rapid and increased response for every single stimulation.
Dopaminergic neurons in the ventral tegmental area activate in response to a surprising reward stimulus when there is no conditioned stimulus to predict it, unless the subject has been conditioned to associate a predictor with the reward at which point the neurons will respond to the predictor rather than the reward itself.
There are high-affinity choline transporters and low-affinity choline transporters for bringing choline back into the pre-synaptic terminal, though I'm not sure yet why. Seems as though the NA+ ion dependant HACT kicks in when acetylcholine levels are depleted or in need of quick replenishing while the LACT just keeps pumping along to maintain baseline levels of ACh.