Optogenetic activation (using Cnoc\ChR1^{Cs.IVS.20xUAS.Venus} with 635 nm (red) light) of Scer\GAL4^VT057358 neurons results in a significant increase in proboscis extension reflex (PER) in the absense of nutritional stimuli, compared to controls; PER in response to 100 mM sucrose presentation is unaffected.

Inhibition (using shi^1.UAS at 30[o]C) of Scer\GAL4^VT057358 neurons, or the combined set of Scer\GAL4^GMR30A08 neurons and Scer\GAL4^VT057358 neurons, does not affect PER in response to 100 mM sucrose presentation, compared to controls; inhibition of Scer\GAL4^VT057358 neurons alone, but not the combined set of Scer\GAL4^GMR30A08 neurons and Scer\GAL4^VT057358 neurons, significantly increases PER in response to presentation of a sweet and bitter mixture, compared to controls.

Inhibition (using shi^1.UAS at 30[o]C) of Scer\GAL4^VT057358 neurons does not affect the reduction in PER response to presentation of 100 mM sucrose seen during quinine application to the proboscis, but sustained aversion after application is significantly reduced, compared to controls; this effect is also seen when silencing occurs only during or only after quinine application.