Scientists May Make the Inner Voice Audible Soon

Recently, neuroengineers have made important progress towards helping people who have lost their ability to speak. By implanting electrodes, the scientists aim to decode the signals produced by the brain when the person wants to speak, and then speak the words out loud via speech synthesis based on the person’s voice recorded when they could still speak. [1] Although this device can help lots of people, I personally don’t think that the inner voice should be made audible.

People are in danger of having their secrets exposed if their inner voices are audible, because technology is not yet readily available to differentiate whether the speech was meant to be mentally processed or spoken out loud.[1] This system works like the previous attempted speech devices, where signals meant for muscles are sent to an AI model that interprets them as words. The model is trained on which words the user has been attempting to speak based on other signals recorded in the past from that specific user. There is a high risk that the thinking process is being heard.

The new study is based on a clinical trial called BrainGate2. [2] One of the participants of the program, Casey Harrell, now uses the system to hold conversations with his family and friends. He lost his voice due to ALS (amyotrophic lateral sclerosis), so he agreed to have electrons embedded in his brain. Surgeons embedded four arrays of little needles in the motor cortex on the left side of his brain. A computer then records the muscle signals, interprets them as words, and synthesizes them into speech.

There is concern about mental privacy with this new device. The secrets inside a person’s brain could be exposed , and it can do far more damage than people think. For example, a president who lost his voice and uses this device might accidentally reveal to enemies a serious vulnerability in the country.

Another drawback is that people with paralysis tend to become fatigued when speaking this way. [3] It can also produce distracting sounds and cause breath control disabilities if paralysis is partial. Scientists took another step further and investigated “inner speech”, or language-based but silent, unspoken thought.

The technology to make the inner voice audible is a significant breakthrough in helping people incapable of proper speech in gaining back the ability to speak. The current approach of capturing attempted speech in the motor cortex is a huge milestone; however, there are drawbacks in this approach. Directly recording a person’s thoughts gives some people the capability to spy on others’ thoughts and privacy. I think that inner voice should not be made audible in a world full of individuals trying to gain access to confidential data and private information for both legal and illegal purposes.

Sources:

1. https://www.nytimes.com/2025/08/14/science/brain-neuroscience-computers-speech.html

2. https://www.scientificamerican.com/article/new-brain-device-is-first-to-read-out-inner-speech/

3. https://news.stanford.edu/stories/2025/08/study-inner-speech-decoding-device-patients-paralysi