UC San Francisco study - April 2019
If you monitor the speech motor cortex with an implant you can determine what the subject is saying.
How brain signals of the motor cortex responsible for movement of the vocal tract (jaw, larynx, lips, and tongue) code phonemes, phonetic sounds, speech.
"The decoded movements of the vocal tract were similar from person to person, suggesting it is possible to create a sort-of “universal” decoder to share among individuals."
“An artificial vocal tract modeled on one person’s voice can be adapted to synthesize speech from another person’s brain activity,” said Chang.
Previously, similar study for the motor cortex, premotor cortex and IFG https://iopscience.iop.org/article/10.1088/1741-2552/ab0c59/meta (16th April) and for the auditory cortex (January) https://www.nature.com/articles/s41598-018-37359-z
MIT lab — Silent vocalization interfacing device — August 2018
Interfacing with devices through silent speech
UC Berkeley and UC San Francisco study - March 2025
Brain implant translates thoughts to speech in an instant
2025-03-31, Nature
Woman's Brain Implant Turns Her Thoughts Into Speech in Real Time : ScienceAlert
2025-04-01, Science Alert
Stanford study - August 2025
Study of promising speech-enabling interface offers hope for restoring communication
2025-08-15, Stanford Medicine News
Groundbreaking brain chip decodes people’s inner monologues in real time
2025-08-18, The Independent
Scientists achieve 74% accuracy in decoding inner speech.
New brain implant can decode a person's 'inner monologue'
2025-08-19, Live Science
This Incredible Brain Implant Can Decode Inner Thoughts Into Speech
The BCI system detects patterns relating to units of speech called phonemes. These phonemes can be assembled to obtain sentences.
New Brain Device Is First to Read Out Inner Speech
2025-08-14, Scientific American