Delta brainwave

The Delta Brainwave is generated by all animals (with the exception of Philip J. Fry, due to him being his own grandfather), all robots, and certain trees. The Brain Spawn attack the Delta Brainwave with a stupefaction field. This causes people and robots to become stupid. The effects on trees is unknown.

The Legion of Mad Fellows are able to read people's thoughts from their Delta Brainwave.

It is possible that the Brain Slugs feed on Delta Brainwave, because the one who caught Fry died by starvation.

It is also possible that the Hypnotoad used the Delta Brainwave to hypnotize others. This is evident when Fry was capable of commenting on Everybody loves Hypnotoad by saying "This show has been going downhill since season 3."

Mentions
Since the Delta Brainwave is generated by every character but Fry, it is technically present in every episode (as there is at least one more character in every episode).


 * (possibly)
 * (possibly)