The Lunar Effect Theory of human behavior is a legend that has been around for approximately 1000 years. It was first popularized by the myth of the werewolf, a fabled concept of European folklore dating back to the middle ages and peaking during the 17th century.
The Lunar Effect Theory of human behavior first came into vogue during the 15th century and peaked during the 17th. It was between those time frames that the myth of the werewolf was becoming more and more popularized by European folklore. This popularization soon became legend and the superstition began to affect the minds of those rural European inhabitants who resided in or near the town of Translyvania.
As far as the legend goes, a man who was bitten by a werewolf would become one during the cycle of the full moon. The Lunar Effect Theory became so provocative an issue that it was frequently associated with explaining various psychosomatic and psyhical as well as psychotic and sociopathic disorders. These behaviors would be intensified during the cycle of the full moon in these European cultures where the superstition persisted.
Yet, it wasn't until the early 1940's when Hollywood would produce a motion picture and called it "The Wolf Man." The movie starred Lon Chaney about a man who goes through the metamorphosis of becoming a werewolf after he's bitten by one; his changes would occur during the cycle of the full moon. It was a movie that ignited fear into the American public, but, of course, that fear didn't become epidemic until the 1950s and 60s.
The Lunar Effect Theory was also used in explaining various forms of pychosis and delusions as well as depression in cultures that had been indoctrinated with this superstitious belief. Thus, the word lunar is derived from its latin roots, "lunacy and/or lunatic"; yet, the theory popularized the concept during the aforementioned time frames which was the reason for the hoopla of activity surrounding its' existence.
Finally, The Lunar Effect Theory is only a theory and has nothing to do with human behavior. It was once an idea that came into existence due to the superstitious beliefs of those rural inhabitants in those backward European cultures. Saying that the theory is a direct correction of human behavior makes it an even more erroneous theory, based on hearsay and not on fact. And as it was popularized during the middle ages is further indicative of how backward those European cultures once were.