While an average human reaction time may fall between , your computer could be adding 10-50ms on top. Some modern TVs add as much as 150ms! Other tools: What's My GPU? If you want, you can keep track of your scores, and see your full history of reaction times.  As the brain receives the incoming data stream, an asynchronous process acknowledges the input and admits it into our consciousness. Consciousness processing takes about 75 to 150 ms. However, many factors can affect an individual reaction time to stimulus. Examples that are often tested as variables in psychophysiology experiments include: age. for the maximum