though in the principles all RASAYANA drugs are supposed to rejuvenate both , the body as well as the mind. a separate class of Rasayana drugs has been described in the text for specially improving the medha ie the memory, will power and intelligence. such drugs are kown as MEDHYA RASAYANA DRUGS , BRAIN TONICS. SANKHAPUSHPI, BRAHMI, MANDUKPARNI, GUDUCHI. MADHU YASTI, JYOTISMATI, VACHA, AND ASHVANDHA.according to me in the ancient books already researches are there.there is no need of any experiments on animals. they are self proved and clearly mentioned,it requires only open minded ness and acceptances of the principles.article isinfomative and useful to every one. it is complete medicine, food and treatment.