This study has two aims: (1) to evaluate therapeutic and neuroplastic effects of a myoelectric upper limb orthosis and (2) to evaluate the functional effects of a myoelectric upper limb orthosis. We plan to recruit 15 Veterans and non-veterans who have Traumatic Brain Injury (TBI) and upper limb impairment, are over 18 years of age and a minimum of 6 months from injury. The study requires 29 visits over 22 weeks and is divided into four parts: enrollment, orthotic fitting, therapy/training (9 weeks), and home use (9 weeks). Therapeutic and functional benefits will be evaluated every 2 to 3 weeks over 18 weeks using simple, short clinical tests.