There are two locations for the Behavioral Research Lab. Experiment rooms B203, B204, B205, and the lab office, B201, are located in the basement of Uris Hall, access through the side of Uris (see the map below). The secondary lab space is on the 3rd Floor of Uris in room 304.
Main Lab (Rooms B203, B204, B205, and the Lab Manager's Office)
The basement lab is on the east side of Uris Hall, visible by a set of double glass doors underneath the staircase leading up to Uris Deli (see map below). Enter by swiping your CUID and walk down the stairs.
Uris 304 (Computer Lab)
To reach the 3rd Floor lab: enter through the main entrance of Uris Hall, then take the elevator (or the stairs) to the 3rd floor, and Room 304 is located all the way down on the right, if you're coming out of the elevator.