  We introduce Brain-Artificial Intelligence Interfaces (BAIs) as a new class
of Brain-Computer Interfaces (BCIs). Unlike conventional BCIs, which rely on
intact cognitive capabilities, BAIs leverage the power of artificial
intelligence to replace parts of the neuro-cognitive processing pipeline. BAIs
allow users to accomplish complex tasks by providing high-level intentions,
while a pre-trained AI agent determines low-level details. This approach
enlarges the target audience of BCIs to individuals with cognitive impairments,
a population often excluded from the benefits of conventional BCIs. We present
the general concept of BAIs and illustrate the potential of this new approach
with a Conversational BAI based on EEG. In particular, we show in an experiment
with simulated phone conversations that the Conversational BAI enables complex
communication without the need to generate language. Our work thus
demonstrates, for the first time, the ability of a speech neuroprosthesis to
enable fluent communication in realistic scenarios with non-invasive
technologies.
