Perception affects the distance at which the Courier is able to detect other creatures on the compass on the heads-up display (HUD). It also factors into some conversations with some NPCs.
6 Perception to question Emily Ortal if "something" happened between her and Benny to get her help working on Yes Man.
Note, this is bugged as the G.E.C.K. is programmed to check the Perception stat for Emily rather than the Courier. Using the commandModAV Perception 1 or ForceAV Perception 6 before talking to her can fix this. JSawyer also patches this.
6 Perception and 35 Science to discuss with God about blocking Father Elijah's eavesdropping through the collars.
6 Perception to correctly interpret Christine about:
Her refusal to leave the Sierra Madre even after defusing the collars.
Asking how the Courier came to be at the Sierra Madre.
Reliving her trauma by going into the elevator shaft in the Puesta del Sol switching station during Mixed Signals.
6 Perception to comment to Ulysses that the Courier does not recognize his voice and so they could not have met him before.
6 Perception to point out to Ulysses that his voice betrays a sense of disdain for ED-E.
7 Perception to notice that Ricky is lying about being from Vault 22.
7 Perception to point out to Walter Phebus that it is not the Mojave heat that has got him sweating, triggering the quest Pheeble Will.
7 Perception to correctly notice that Lady Jane is lying about being unable to pay her debt during Debt Collector.
7 Perception to tell Keller that he gives himself away as an NCR Ranger too easily during Dealing with Contreras.
7 Perception and 7 Intelligence to catch Keller in the act of not knowing the code phrase, exposing him as an NCR Ranger and trying to arrest the Courier during Dealing with Contreras.
7 Perception to get Christine to admit that she will not allow Father Elijah to leave the Sierra Madre alive during Last Luxuries.
7 Perception to comment to Doctor Mobius about the bullet that Doc Mitchell had to take out of the Courier's brain after getting shot.
Early Bird (+2 between 6 a.m. and 12 p.m., but -1 between 6 p.m. and 6 a.m.)
Notes[]
Despite the description given on the Vit-o-matic Vigor Tester, Perception does not actually increase V.A.T.S. or regular accuracy in Fallout: New Vegas.
It is possible to get a Perception of 10 with only 6 natural points, by combining the Four Eyes trait, lucky shades, a hat and the Perception Implant (6 - 1 + 3 + 1 + 1 = 10).
Similarly, it is possible to achieve a temporary boost to 10 from a mere score of 2 using both kinds of Mentats, absinthe, coyote tobacco chew, and a hat (2 + 4 + 3 + 1 = 10).
By having access to DLC items, it is possible to get up to PER 10 without the Four Eyes trait, even if starting at only 1. The elite riot gear helmet (+2) can be worn together with the 1st Recon beret (+1) and a stealth suit Mk II (+1). After installing the Perception implant, Perception is at 6. From there, any combination of Perception-enhancing chems can reach 10.
Doc Mitchell will have a unique comment if the Courier's Perception attribute level is the most extreme (highest or lowest) during character creation, as follows:
Extreme
Comment
Low
"Now I ain't no optometrist, but maybe we should fit you for some glasses while you're here."
6 Perception and 35 Science to discuss with God about blocking Father Elijah's eavesdropping through the collars.
