Star Trek: Voyager - Season 5 Episode 19 -

Voyager gets trapped in "chaotic space," a kind of Bermuda Triangle, where sensors are useless and a straight line sends them running in circles. In an attempt to relay to Voyager that they are not welcome, the inhabitants of chaotic space activate a genetic defect in Commander Chakotay, who interprets the warnings and instructions in the form of hallucinations including his Grandfather and his boxing training at Starfleet Academy.