In order to understand this we have to explain what the brainwave frequencies are . We are talking about the functioning frequency of the brain which varies according to the conditions and/or the type of person.
These are Beta, Alpha, Theta and Delta.
Delta 0,5-4 Hz is the state of the deep dreamless sleep, there is no consciousness there, at least not when this is the main wave pattern.
Theta 4-7 Hz, is the REM sleeping condition where dreams appear, or in case of being awake, the very deep relaxing state.
Alpha 7-14 Hz, is the relaxing mode, usually comes immediately when the eyes are closing.
Beta 14->21 Hz is the everyday awake functioning mode, where the brain analyzes, works hard and tries to survive.
In the 2 middle ones the person is more connected with subconscious mind and intuition.
What many people don't know is that except of the main frequency, the brain functions also in harmonics. Part of it may function in Beta and another part in Theta which makes easy inspiration and intuition in everyday life, take wise decisions in business or in a relationship and be relaxed in a stressful situation.
Another thing many people don't know is that the main frequency of the sensitive peoples' brain is low, usually Alpha or Theta and has harmonics in Beta for being aware of the world.
One example is, if you are a sensitive person, when you are driving you are in a very relaxing state (of course not the first months after you get the license) and while the hands and the feet are doing what they do automatically, the brain is calculating the position of the cars and other objects or subjects around in space and time, you have actually nothing to do. It's kind of automatic process. And it's exactly the way of driving that causes the least accidents if any, because in this state intuition functions very well too and you can avoid troubles if you listen to it.
The trouble is that non HSP in this state are in danger to sleep.
My experience was, once I went to visit some friends, about 3 hours driving from home, and they had a new espresso machine, so I had 3 coffees. The trouble was that on my way back my brain was in so high frequency that the trip was a huge effort. I had to think of every movement of hands and feet, to check every moment the position and directions of the cars around me because the automatic system was not functioning. I arrived at home so exhausted and the same time unable to sleep because of the coffee.
So under normal conditions HSPs are living mainly in Alpha or Theta frequencies without sleeping and this is where sensitivity comes from. It's also the reason for often losing attention to what they do and appear to have all these "disorders".
Coffee and power drinks are not the best for sensitive people. Since they are not made for living in high Beta they get tired very soon and they lose all the abilities that sensitivity offers. Maybe it makes easier to be focused on things, like using Ritalin, but there is no use for it because if you have your attention on what you are doing but lacking the inspiration you are not very effective.
So under normal conditions sensitive people are in low frequency state, and in this state they can be relaxed, creative, inspired and feeling at home. They also have high self-esteem and a lot of power.
But if a sensitive person is trying to correct this condition, with drugs or thoughts, trying to fit in a non-natural or unwanted way of life, just for pleasing others, or has been abused and rejected, verbally or physically, then things are getting difficult. And in this case we have the so called neurotic type of sensitive people, who feel always like victims, everything is annoying and the world is the worse place to live.
Sensitivity is a natural thing and under natural conditions is at ease and fully functioning. And the brain frequencies are also part of this nature. So when you experience difficulties instead of trying to change your nature, because others are telling you so, change the environment and your way of life.
Let's put it this way, if you try to turn a lion into vegan, will suffer and die.