Mental Privacy
Mental privacy is the interest in controlling access to information about one's own brain and mind. In the neurotechnology context it extends informational privacy to neural data — recorded electrophysiology, imaging, and any inferences drawn from them — including states the person may not consciously report or even be aware of, such as attention, affect, disease risk, or automatic responses.
The distinctive threat is inference, not raw signal: a low-resolution EEG stream is not a 'thought transcript,' but decoders can extract statistically reliable correlates of covert states (recognition, preference, error monitoring) that were never intended for disclosure. Because these inferences can be made passively and continuously, consent given for one purpose (device calibration) can silently enable another (affect profiling).
A consumer 'focus-tracking' wearable logs an attention index throughout a workday; the raw EEG seems innocuous, but the derived time series reveals when the user was disengaged, stressed, or drowsy — inferences an employer could misuse.
The privacy risk lives in the inferable derived states, not in the raw waveform.
Distinguish mental privacy from freedom of thought: privacy limits access, whereas the internal freedom to think is a separate, near-absolute protection. Be honest that current decoders are noisy and context-bound, far from general mind-reading — the risk is real but often overstated.