In this study, we have investigated the brain activation characteristics of students according to the familiarity with physics term and the physics unit using a functional near infrared spectroscopy device capable of measuring the changes in brain activation in real-time. As a result of analyzing the brain activation data, it was found that the brain activation change of the students in the left hemisphere midfrontal gyrus increased in the familiar physics words and decreased in the unfamiliar physics term. This is because the image and conceptual associations are made when students see the familiar physics term. In addition, as a result of comparing the brain activation characteristics for each physics unit, the significant brain activation was found in a part of the dorsolateral prefrontal cortex included in BA46 in the thermodynamics unit, which was related to the association of algebraic concepts with the thermodynamic term. Additionally, in the case of the wave unit, it was found that significant brain activation occurred in a part of the orbitofrontal cortex corresponding to BA47. This is thought to be due to the musical syntactic association with the wave term. The results of this study are expected to not only increase the possibility of neuroscientific research techniques for educational research, but also be used as educational neuroscientific bases for effective physics teaching and learning strategies.