The disclosure provides for easy, reliable, and rapid screening of a mild traumatic brain injury (mTBI) based on a modeling of a subject's tracking of a dynamic target during the course of a simple motor tracking task. The gathered tracking data can be used to calculate tracking errors between the subject's actual input (e.g., grip force) and the intended target input. The tracking errors may be used to generate numerical values for model parameters that correlate the subject's responses to the tracking errors during the course of the dynamic motor tracking task. A classification model may be used to compare the model values to multi-subject model values of known diagnoses for mTBI. The entire screening process can be effectively administered in a matter of minutes or less, and with a high degree of accuracy.