The angle of attack makes this a deflector with swirling vortexes of air behind it. I can see some altering of air course, but think there is an air-brake effect as well.
Angle Of Attack
McLaren does a true air-brake, and the angle seems to be a bit greater.
McLaren MP4-12C
The Lambo's channeling of air via the vertical struts is an innovation I have not seen before, at least not in this specific manner.