Electroantennography

Electroantennography or EAG is a technique for measuring the average output of an insect antenna to its brain for a given odor.

The technique was invented in 1957 by German biologist Dietrich Schneider[1] and shares similarities with electro-olfactography.

[2] Electroantennography is usually performed either by removing an antenna from the insect and inserting two chloride silver wires for contact onto the two ends and amplifying the voltage between them while applying an odor puff to see a deflection as in the figure, or by leaving the animal intact and inserting a ground wire (silver/silver chloride) or a glass electrode filled with a buffer solution to some part of the body, usually inserted into an eye, and another to the tip of the antenna.

The technique is widely applied in screening of insect pheromones by examining the responses to fractions of a compound mixture separated using chromatography.

Further detailed examination of the odor response at the olfactory sensory level can be done by sensilla recording.