Sony has patented a mouth-based sensor that analyses your saliva

A Sony patent has revealed details for a sensor that measures the changing chemical make-up of your saliva.

The miniature sensor would fit behind your two front teeth and detect the levels of enzymes and hormones which can indicate your emotional state, the patent (dug up by NeoGAF) explains.

The documents were published today via the US Patent Office but were filed back in October 2012 by Dr. Ozlem Kalinli-Akbacak, a research engineer at SCEA.

"Emotion recognition or understanding the mood of the user is important and beneficial for many applications; including games, man-machine interface etc.," the patent states. "Emotion recognition is a challenging task due to the nature of the complexity of human emotion; hence automatic emotion recognition accuracy is very low."

This new system would use a suite of sensors all over a user's body - such as a finger-based ring that could detect your heart rate, blood pressure and respiration (similar to Nintendo's abandoned Wii Vitality Sensor concept).

A head-based sensor "band/cap" would measure brain activity and stimulation, while another part of the patent mentions sensors embedded within a PlayStation controller - an idea Sony is rumoured to have explored and then ditched for the final PS4 pad.

All of this data would then be transmitted to a "computer system" to gauge a user's physical reactions.

Despite today's publication it's unclear whether Sony still intends to do anything with the idea. The project doesn't appear to be connected to the company's newly-announced Project Morpheus VR tech, however.