Temporal psychosis

From Memory Alpha, the free Star Trek reference.

Temporal psychosis is an illness affecting the nervous system, causing irrational behavior. The use of a temporal transporter to "recruit" an individual from his/her original timeline more than three times leads to an increased risk of temporal psychosis. Sensory aphasia is an early warning sign of potential temporal psychosis.

In the 29th century, Captain Braxton eventually suffered temporal psychosis as a result of his interactions with the USS Voyager. This led him to attempt to destroy Voyager using a temporal disruptor. (VOY: "Relativity")