Mental time travel a unique human capacity: Study

London: Humans appear to be the only species who are able to remember events that they had experienced and mentally time travel not only into the past but also the future, suggests new research.

The researchers found no definitive evidence for foresightful behaviour in animals.

In order to answer the question if animals are capable of mental time travel, the researchers relied on published experimental studies and matched the results with their own model.

"Some animals indeed appear to possess episodic memory. There is, however, no evidence that they are able to construct, reflect and compare different future scenarios like humans are. We, therefore, do not believe that animals are capable of mental time travel," said one of the researchers Sen Cheng, professor at Ruhr University Bochum in Germany.

For example, the ability of squirrels to cache food in autumn for the winter can be interpreted not as an anticipatory activity, but rather as innate behaviour, the researchers said.

"The squirrel would hoard food even if it had been fed in the winter all its life," Cheng noted.

The new model that the researcher developed suggests a new relationship between mental time travel and episodic memory -- the memory of autobiographical events that can be explicitly stated.

The research team assumed that mental time travel is composed of different components.

"Component one are memory traces from episodic memory. That means: fairly accurate representations of personally experienced episodes, where each trace represents a particular experience," Cheng explained.

Component two is the ability to construct mental scenarios. By this, the researchers mean dynamic representations of past or expected situations that are not isolated but rather can be embedded into larger contexts and be reflected.

If, for example, someone misplaces their key, they mentally travel back to places and situations where they still had the key.

The study was published in the journal Neuroscience and Behavioral Reviews.