Atascadero, California-based brain training technology maker SenseLabs (formerly Neurotopia) raised $4 million, according to an SEC filing.

The company has developed a tool to help athletes train themselves to be mentally stronger.

To use the device, SenseLabs users wear its a brain sensing headset to  gather data the brain's electro-chemical activity, according to an old report from P3 Lab, which was written before SenseLab's rebranding. SenseLab's system tracks, for example, where an athlete is on the spectrum of focused to distracted throughout their workout. That data is presented in graphs, scores, and other visual representations via a tablet.

Based on previous reports, the company also turned the data into video games that are influenced by how focused the player is.

Similar kinds of devices have also been developed by companies looking to help people reduce stress levels.

One such device, from Los Angeles-based Melon (formerly Axio), launched its device on Kickstarter in June 2013 and raised its $100,000 goal within 60 hours. At the time, co-founder Arye Barnehama told MobiHealthNews Melon users will wear the Melon headband to monitor focus levels for different activities. Melon's app will also offer suggestions if the user begins to lose focus.