Chakotay experiencing temporal flux
Temporal flux is a type of temporal anomaly where time itself keeps changing. The constant flow of time as we know it continuously alters, jumping from future to past to present and vice-versa. Tachyon beams have been known to help correct temporal fluctuations and anomalies. (Star Trek Generations)
Based on the readings of a being disguised as a Romulan, discovered in 2369, Data determined that any species that had nonconforming cellular structures, in terms of bio-electric patterns found in a state of temporal flux, were determined not to be native to the normal space-time continuum. (TNG: "Timescape")