This review article published in 2015 provides insight into the benefits of supplemental phosphatidylserine in cognitive health as we age, stress responses and exercise endurance. In this review, 127 articles were included and supplemental dosages ranged from 300 mg/day to 800 mg/day as divided doses (most frequently as 100 mg TID.) A number of promising open label trials showed benefit in cognitive parameters and inspired a number of double blinded randomized controlled trials.
Glade MJ, Smith K. Phosphatidylserine and the human brain. Nutrition. 2015;31(6):781-786. doi:10.1016/j.nut.2014.10.014 https://pubmed.ncbi.nlm.nih.gov/25933483/