RecruitingDevice studyUsing Non-invasive Brain Stimulation to Treat Word Finding Difficulty in Chronic Traumatic Brain InjuryThe purpose of this study is to learn more about how brain stimulation affects word finding problems in people who have a traumatic brain injury (TBI). The type of brain stimulation used is called transcranial direct current stimulation (tDCS). tDCS delivers low levels of electric current to the brain and high definition tDCS (HD-tDCS) delivers the current with multiple electrodes on the scalp. This current is delivered with HD-tDCS to parts of the brain that may help with remembering things. The investigators hope that this can help to improve word finding and memory problems in people with TBI.