Probably there are more by now. As I recall this data is great for essentially saying "you should go get a real test." No one is diagnosing - just saying that a certain, say, eye movement slowness is correlated and you can detect it much earlier than a hand tremor or other more prominent symptoms.
https://techcrunch.com/2018/02/17/righteyes-portable-eye-tra...
https://techcrunch.com/2022/05/24/neuralight-aims-to-track-a...
Probably there are more by now. As I recall this data is great for essentially saying "you should go get a real test." No one is diagnosing - just saying that a certain, say, eye movement slowness is correlated and you can detect it much earlier than a hand tremor or other more prominent symptoms.