Wearable Sleep Trackers Use Brainwave Data for AI Training Without Explicit Consent

Undisclosed Use of Brainwave Data

An investigation by Science, in collaboration with the Pulitzer Center's AI Accountability Network, revealed that companies manufacturing wearable sleep trackers are utilizing customer brainwave data (electroencephalography or EEG recordings) to train artificial intelligence models. These companies have amassed tens of millions of hours of EEG data from users.

AI Model Training Without Explicit Consent

Several neurology companies, including Interaxon (maker of the Muse headband) and Emotiv, are developing brain foundation models using these recordings. The investigation found that these companies initially failed to explicitly state this use in their privacy policies, meaning customers were not fully informed that their brainwave data would be used for AI training.

Interaxon, for example, has trained an AI model with approximately 50,000 hours of EEG recordings, stating that identifying information is removed before use. However, its privacy policy did not clearly disclose this practice until after the investigation.

Privacy Policy Updates and Legal Implications

Following discussions with Science, Interaxon updated its privacy policy to explicitly inform users about the use of their brain recordings for foundation model training. Nadia Kumentas, Interaxon's Chief Marketing Officer, acknowledged the need for explicit user information. The late disclosure for data already used could expose the company to potential lawsuits.

The investigation also highlighted broader privacy issues, noting that over two-thirds of the studied companies allowed corporate data transfers without user consent. This raises concerns about data ownership and control, particularly if a neurotechnology firm is acquired. While Colorado and California have amended consumer privacy laws to cover neural data, other states have not yet done so.