Synaptic failure
Synaptic failure was the loss of the synaptic functions of the brain.

Following an accident aboard a Bajoran transport in 2371, Vedek Bareil Antos suffered from a synaptic failure and was treated by Doctor Julian Bashir aboard Deep Space 9. Bashir applied direct neuro-stimulation to the brain stem, while the left temporal lobe later began to show signs of massive synaptic failure after Vasokin had been administered. ()

Due to Tom Paris' punishment on the planet , he suffered from reactions to the memory engram transplanted into his brain. At the request of Captain Kathryn Janeway, the Banean doctor supported her desire to transport Paris aboard  to prevent a general synaptic failure. ()

In 2373, Ahni Jetal suffered massive synaptic failure after being attacked by a hostile alien. ()

In 2377, Jaryn told The Doctor, while his program was inside Seven of Nine's cybernetic matrix, that a viral weapon used by photonic insurgents caused complete synaptic failure within days. ()

Medical conditions