PSV remain top with 50 points after 24 matches, two ahead of Ajax Amsterdam, who were held to a 1-1 draw by mid-table ADO Den Haag, while Feyenoord remain third on 47.
Sloppy play from Dutch international Jordy Clasie earned Tim Matavz the chance to set up Jeremain Lens 11 minutes before the break to open the scoring for PSV
Two minutes after the break, Clasie made amends for his mistake when he connected with Schaken who scored the equaliser.
Italian Graziano Pelle settled the win midway through the second half when he turned away from Mathias Jorgensen and surprised goalkeeper Boy Waterman with a well-placed shot into the left corner.
"Despite our halftime lead my team never realised the importance of this match," PSV coach Dick Advocaat told reporters.
"But the way we gave away the goals in the second half can't and shouldn't happen and therefore Feyenoord deserved the win."
Late in the game, Dutch internationals Joris Mathijsen and Lens were involved in a row on the pitch which continued inside the stadium after the match.
A defensive blunder from Ajax's Niklas Moisander allowed Tjaronn Chery to open the scoring for Den Haag after 30 minutes with a fine lob but five minutes before time Lasse Schone salvaged a point for the home side when he netted a deflected corner.
Jacob Mulenga scored twice as sixth-placed Utrecht cruised to a 4-0 home win over 10-man Roda JC Kerkrade who had Abel Tamata sent off after 18 minutes for a professional foul.