“…Because AAC-BCI systems can be operated without reliable volitional movement, they offer a potential means of communication access for people with locked-in syndrome (LIS) or other forms of severe speech and physical impairment (SSPI) who may have difficulty using other AAC access methods (e.g., eye gaze, switch access, touch access) (Akcakaya et al, 2013;Rezeika et al, 2018;Pitt et al, 2019). Researchers have explored the use of AAC-BCI systems by individuals with a variety of medical conditions that may cause SSPI, including amyotrophic lateral sclerosis (ALS) (Kübler et al, 1999;Wolpaw et al, 2018;Medina-Juliá et al, 2020;Miao et al, 2020;Peters et al, 2020), muscular dystrophy (Halder et al, 2016a), stroke (Kaufmann et al, 2013a;Kleih et al, 2016), traumatic brain injury (Combaz et al, 2013;Lesenfants et al, 2014), cerebral palsy (Käthner et al, 2017), and spinal muscular atrophy (Zickler et al, 2011). Many participants in these studies presented with classic LIS (in which only eye movement and blinking are preserved) or incomplete LIS (in which small movements of other body parts are possible) (Bauer et al, 1979;Smith and Delargy, 2005).…”