Who gets to decide?: Substitute decision making following severe brain injury with communication impairment.

In our prior study (Malhi et al., 2021), we demonstrated that cognitive ability may be masked by communication impairments. We used binary choice (i.e., yes/no) neuropsychological tests to assess cognitive functioning in four patients with severe brain injury and communication impairments. In this study, we aimed to better understand the decision-making process of their substitute decision makers (SDMs). We interviewed SDMs - two SDMs were supporting patients in the minimally conscious state, one SDM was supporting a patient who had locked-in syndrome and was an augmentative communication user, and the last SDM was supporting a patient who was an alternative communication user. SDMs were performing various roles ranging from making all decisions to simply being the vocal advocate (for the augmentative and alternative communication users). SDMs described heuristics they used to make decisions, and all identified auditory comprehension capabilities as being an important element for decision making. We argue that if mode of communication is established and utilized, and binary choice neuropsychological tests are used to ascertain cognitive functioning, SDMs may more confidently make low/medium stakes decisions based on the present condition and context, rather than solely on past wishes and values before capacity was in question.