Special Containment Procedures
SCP-991-1 is to be kept in a sealed container at Site-19. SCP-991-1 may not be stored if there is SCP-991-2 present. Access to SCP-991-1 for testing or use in interrogation/re-education requires the approval of a class-4 personnel.
SCP-991-1 is a 19 cm long syringe. While the plunger is made of steel, the barrel and needle appear to be composed of previously unknown materials. When inserted into the blood vessel of a human and drawn, SCP-991-1 fills with an unknown black fluid, given the designation SCP-991-2. Once drawn from an individual (henceforth known as the donor), the plunger of the syringe cannot be pressed unless the needle of SCP-991-1 has been inserted into another human. Visual analysis of SCP-991-2 has shown it to have a significantly lower viscosity than blood, but direct analysis has proven impossible, due to the nature of SCP-991-1. Attempts to draw SCP-991-2 from a vein using a normal needle immediately after it was injected with SCP-991-1 have met with failure; apparently SCP-991-2 either disperses the instant it is injected or becomes immaterial.
When injected with SCP-991-2, the individual (henceforth known as the recipient) will instantly take on the thoughts, emotions, and memories at the forefront of the donor's mind during SCP-991-2 extraction. The further back the plunger is drawn (i.e. the more SCP-991-2 present), the more potent and permanent these ideas will be. Because it is the thoughts most prevalent in the donor's mind that determine which are transferred, some level of control can be achieved. The process is imperfect, however, as unwanted ideas usually manifest in the recipient alongside the desired ones. Whether this is an aspect of SCP-991 or a lack of focus on the part of the donor has yet to be determined.
Regardless of the cause, the "thought leak" caused by SCP-991 often results in the recipient becoming unhinged, especially if he or she receives multiple injections. They begin to possess conflicting viewpoints and ideas, and exhibit symptoms similar to those of a paranoid schizophrenic. For this reason, use of non-D-class personnel as the recipient is highly discouraged.
SCP-991 appears to actually transfer thoughts, as any idea taken from the donor no longer appears in his or her mind; transferred memories, emotions, and even opinions seem to vanish from the donor when SCP-991-1 is drawn. After repeated donations, donors often begin to exhibit symptoms consistent with Alzheimer's Disease. In some cases, this will result in the loss of a fundamental faculty of the donor, such as swallowing, breathing, or blinking. In such cases, subject is to be euthanized once all relevant data on their psychology has been taken.
Use of SCP-991 on Foundation personnel is highly discouraged, and requires the consent of both the donor and recipient, as well as the approval of two (2) class-4 personnel.
SCP-991 has proven very useful for interrogation. Cooperative D-class can be used as donors for ideas of cooperation, to be injected into the individual being interrogated. Conversely, since the information desired is often at the forefront of the individual's mind, SCP-991 can be drawn from the individual and injected into another, in order to obtain the information forcibly. It is encouraged to use cooperative D-class for this as well, however, in order to prevent "thought leak" into Foundation personnel.
SCP-991 was recovered from ████████ █████ Mental Institution, after the Foundation received reports of doctors at the institution going insane. Upon recovery, SCP-991-1 was found to be filled with SCP-991-2. When injected into a D-class subject, the individual began to behave in a manner consistent with dissociative identity disorder.