I have not tried hypnosis. When I was starting to get serious about target and competition, I found most were using clickers as they held on the target. When I quit competition, I found the following method to bypass the problem of holding on a target. The first deer I shot, was running from my right to left and I nailed it, like shooting birds with a shotgun. Although, beating target panic sounds easy, it isn't for most and they end up putting a clicker on their bow.
Target panic is a learned habit, to undo it takes some time and persistence. If you had a habit of aiming, aiming to the point where it was difficult to hold on a spot, try the following every practice session for as long as needed. Remove all targets, or cover a bullseye, or animal target with a 13 gal. white kitchen garbage bag. Just hold it in place with two nails. If you have straw, cedar or cardboard bales, you can skip the white bags.
Standing close to the backstop (bales), concentrate on a smooth and draw and release. Rhythm is key to success. If you have used a shotgun to hunt birds, you know you can't hold on the bird or you'll shoot behind it.
When ready, pick a spot on the bale and concentrate on it without looking at the arrow or another spot; draw and release when you reach full anchor, without holding. Each shot should be rhythmic draw and release. Develop a smooth and rhythmic process. Repeat the process, aiming at the same spot a second time. Move to a different spot every few shots, so you aren't breaking arrows.
It is best to stand close, like 10 yards and to end a short session on a positive note. The new habit forming is easier to learn if you don't try to hold. Keep the sessions short and end on a positive note. Your brain will create a learned response and the habit will become a subconscious response.