**5. Conclusions**

This study implemented an intervention involving a combination of LoRETA neurofeedback and HRV biofeedback for eight weeks, based on individual EEG baseline assessments. Eleven participants with PPCS were included in the intervention group (seven that finished the protocol), 12 in the PPCS control group (nine that finished the protocol), and eight healthy control participants. Considering the PPCS intervention group as a whole, this combined intervention did not improve symptoms or driving simulation performance. However, some of the individuals did show improvements. This may indicate that this intervention is effective for a subgroup of individuals with PPCS, or perhaps that the intervention needs to be further individualized to optimize participants' responses. Specifically, the nature of the symptoms, rate of improvement, and length of symptom persistence may need to be considered to individualize the protocol. The results of this study also emphasize the importance of evaluating fitness to drive following a concussion, as well as the need for return-to-drive guidelines for individuals experiencing symptoms following a concussion.
