Generally, you are responsible for your student loan debt. The Lender has no idea if you genuinely have traumatic brain injury preventing gainful employment unless you notify them. As with anyone having difficulties repaying student loans, you should call the Lender and explain the circumstances. They may have forbearance options that would be periodically revisited to see if you are still without the ability to repay. Often a forbearance agreement will last 12 months meaning you would not have to make payments during that period. Usually, the interest continues to accumulate during that time increasing the total debt. You will need to contact the Lender to receive the necessary paperwork. The Lender will hope that one day you will be able to find gainful employment and begin repaying the loans. That's why the forbearance will be revisited at the end of each period.
If you are asking whether Bankruptcy can discharge the student loan debt, that is harder to say without more information about your injury and your prospects for future improvement. Generally, it is very difficult to discharge student loan debt; but it is not impossible. You should discuss your specific circumstances with an attorney who handles Chapter 7 petitions for more advice if that is how you want to proceed.