London, Oct 20 (IANS): The chemical produced by decaying tissue of dead bodies can produce a fight-or-flight response in humans, researchers have revealed, suggesting that humans, like other species, can perceive certain scents as threatening.

These are the first results to show that a scent emanating from a specific chemical compound called putrescine can be processed as a threat signal.

"So far, nearly all the evidence for threat chemosignals has come from those that are transmitted by body sweat,” said Dr Arnaud Wisman from University of Kent's school of psychology.

In four different experiments, researchers exposed people consciously and non-consciously to putrescine.

The results show that putrescine can serve as a (non-conscious) signal that initiates threat management responses.

The researchers found that even brief exposure to putrescine increases vigilance, followed by the readiness to either escape (flight), or engage in aggressive readiness (fight) when escape is not possible.

One of the outcomes of isolating putrescine in threat management processes is that it may help in determining which sensory and brain pathways are involved in chemosensory threat detection and processing, the authors noted.

The paper was published in the journal Frontiers in Psychology.