The home side turned in an impressive shift against the French champions, but were undone by a first-half goal from PSG midfielder Thiago Motta.
"We did well in our play from a tactical point of view," Gourcuff told reporters.
"We were disciplined in our positional play and the players were very motivated because we were up against PSG. We put some good moves together and had good chances.
"We've got problems taking our chances at the moment and they managed to make the most of one acceleration in play to make the difference."
The result sees Lorient sitting in 12th position in the Ligue 1 table.