Waltham, Massachusetts-based Affectiva, which spun out of the MIT Media Lab in 2009, has raised $12 million from Kleiner Perkins Caufield Byers and Horizons Ventures to build out its emotion measurement technology for advertisements and for various medical research initiatives. According to various media outlets, the company has now raised more than $20 million, including grants from the National Science Foundation.

In July 2011 the company raised nearly $6 million from WPP.

Affectiva plans to primarily use the funds to build out its emotion sensing platform and begin leveraging it for measuring emotional response and engagement to various online videos and games. Secondarily, the company plans to use some of the investment to develop its wristworn wearable device, the Q Sensor, which can detect emotional response via the user's skin. Last December the company officially unveiled its Q Sensor device.

The Q Sensor device has already been used at Boston Children's Hospital for patients with epilepsy and "hundreds" of other research groups and institutions.

The investment brings two new advisors to the company: KPCB's Mary Meeker and Horizons' Frank Meehan.

More details about Affectiva's latest round of funding over at TechCrunch.