Synaptic Transfer (Earth-1993)

Synaptic Transfer is a process by which two people can possess a shared dream-state, thus granting an individual access to an unconscious person's mind. The process can be used to communicate directly with a person in a coma and search their memories, and Walter Bishop even claims to have used the technique to extract information from a corpse - although he also claims this is only possible if the corpse has been dead for less than six hours.

Functionality
To allow access to the unconscious person's mind, a conscious individual must have an electromagnetic probe inserted in the base of their skull and be put into a drug-induced coma by a mixture of Ketamine, Neurontin, LSD and other substances. The individual is then immersed in water, whilst wearing as few clothes as possible, and allowed to fall unconscious.

The probe is attached to a relay which allows it to share information with the probe inserted into the unconscious subject, and the brain patterns of both are monitored through a computer and data recording equipment. The searcher often experiences hallucinations before reaching a shared dream-state with the unconscious subject; evidence shows these are often the searcher's own memories and may not have any apparent connection with the subject or information they are trying to reach. Once the searcher's brainwave patterns synchronize with the unconscious subject they are able to communicate directly and can access the unconscious subject's thoughts and memories; it is unknown whether or not the subject can do the same with the searcher's memories.

Source

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