Advance directives, substituted judgment, and the best-interest standard all have limitations that constrain their usefulness in making medical decisions for patients who cannot choose for themselves.
Our ability to infer mental states from fMRI scans is still rudimentary, but the time may be approaching when neuroimaging can be used to indicate witnesses’ reliability in court proceedings.
New brain imaging suggests that asking patients to put themselves in their surrogates’ shoes when thinking about advance directives might lead to directives that better line up with what surrogates think they should decide.