This is also just one example of what the CIA does. They killed an elephant with a single dose of LSD. Used it on foreigners, US citizens, etc... The Rest Is Classified did a great series about it (1,2)
Yeah, it's exponential. You'd have to double the dose each day to achieve the same result as the day before. Otherwise they're just gonna have some mildly distorted thoughts and a nasty headache.
1 https://www.youtube.com/watch?v=kO0bQGf3uH8 2 https://www.youtube.com/watch?v=gKnoZhbqTfM