What do you mean by cut-off
Well you technically need to meet the min. stated GPA requirement to even have your application accepted by the graduate school (usually 3.0). From here your application is sent to the department for further review. Now here is where it gets crazy, especially for the biomedical sciences (neuroscience included).
A "cut-off" is then set by the adcom. for minimum GPA, and GRE (general, and subject if applicable). Here, an administrator sits down with the applications, and sorts them. The GPA minimum cut-off may be a 3.25, or a 3.40, or a 3.50. Meaning if your GPA is less than than the cut-off, you may be out of the running for 1st round offers, and maybe out of the running for any offers, depending on the strength of the other applicants. Someone will possibly have to "rescue" your application for additonal consideration after 1st, 2nd, or 3rd round offers.
The GRE requirements may be >1200 (or whatever this is on the new scale, basically >70% Quant, >50% Verbal). Again, you may be out of the running for 1st round offers, and maybe out of the running for any offers, depending on the strength of the other applicants. Technically, the GRE shouldn't be used this way, but it is. ETS themselves advises against this practice, but it still happens.
From here, the adcoms read applications, LORs, personal statements, etc. Here is where the interviews are handed out. If you are in the "rescue" situation, you will need an advocate in the room to convince his/her fellow adcom. members that you deserve a review of your application and possibly an interview in the later rounds, or even to get put on the waiting list.