in a healthy and intelligent individual, it acts as a sensor, indicating when something outrageously stupid has been processed. it tends to result in facepalming, headaches, or sympathetic lulz in defense of knowing that the demise of mankind is imminent.
in an unhealthy or stupid individual, it provides a positive-feedback mechanism, resulting in the individual gaining reward for filling their brain with even more useless bullshit. stimulation of the gland in this type of individual brings about erratic, borderline retarded behavior, and in fact causes them to emanate even more derp to the surrounding environment. this can lead to a derp cascade, which enthralls masses of stupid individuals to do stupid things.
(stupid) DDDDDDDERRRRRRRRRRPPPPPPPPPPP! NUOH MAH GAWD KIM KARDASHIAN DDDEEEEERRRRPPPPPPPPPP!!!!