Abstract: Locked-in syndrome, caused by brainstem stroke or ALS, can leave an individual “trapped” inside of their own body and unable to move or talk. Brain-computer interfaces (BCIs) that detect the desire to move directly from the brain can restore communication via thought alone. My work has developed handwriting and speech BCIs that set new performance records, showing for the first time that the intention to talk or write can be neurally decoded at rapid speeds in people who have not done so for years. This unprecedented access to neural activity in the human brain has also led to new fundamental neuroscience insights – for example, that the whole body is represented in each part of the motor cortex, contradicting the traditional “homunculus” model. My future work will seek to expand the scope of what BCIs can do to disorders such as Broca’s aphasia (loss of speech/language production due to stroke), paving the way for BCIs to be a routine approach to solving otherwise intractable neurological disorders.