From the International Journal of Human Potential Development, this pic represents the Greater Cognatogen.
Prerequisite: Alchemist 12, cognatogen discovery or cognatogen class ability
Benefit: The alchemist’s mutagen now grants a +4 natural armor bonus, a +6 alchemical bonus to one mental ability score (Intelligence, Wisdom, or Charisma), and a +4 alchemical bonus to a second mental ability score. The alchemist takes a –2 penalty on both associated physical ability scores as long as the mutagen persists, and takes 2 points of ability damage to both associated physical ability scores when the cognatogen ends.