Three of the faces in Michelangelos Sistine Chapel frescos are recognized as portraits: his own sardonic self-portrait in the flayed skin held by St Bartholomew, itself a portrait of the scathing satirist Pietro Agostino, and the depiction of Mary as a portrait of his spiritual soulmate Vittoria Colonna. The first analysis was of the faces of the depictions of God and of the patriarch Jacob, which were rated by AI-based facial ratings as highly similar to each other and to a portrait of Michelangelo. A second set of young faces: Jesus, Adam and Sebastian, were also rated as highly similar to God and to each other. These ratings suggest that Michelangelo depicted himself as all these central figures in the Sistine Chapel frescoes. Similar ratings of several young women across the ceiling suggested that they were further portraits of Vittoria Colonna, and that she had posed for Michelangelo as a model for the Sistine Chapel personages in her younger years.
Christopher W. Tyler, "Special Session on Art: Perception and Cognition AI Identifies Michelangelo's Covert Self-Portraiture in the Sistine Chapel" in Electronic Imaging, 2024, pp 202-1 - 202-3, https://doi.org/10.2352/EI.2024.36.11.HVEI-202