I don't think eye strain can cause insomnia. On the contrary, it is possible to have eye strain from insomnia. Insomnia refers to difficulty of sleeping for some reasons. As it is difficult for patients with insomnia to sleep, it would definitely lead to eye twitching, eye strain and headache. It is easy to understand. If we prolonged the working time of eyes, the muscles would be strained so the eye strain is resulted. To prevent eye strain, you need to change the focus of vision by taking breaks. It can help relax the muscles. Eye massage could also bring this effect. Through gentle pressing on some points to help the muscles relax and promote the blood circulation around eyes. To prevent insomnia, you have to find out what caused it. I sometimes suffered from insomnia which is very miserable. Now I always have half cup of warm milk before sleeping to help me sleep well. Meanwhile proper exercises could be helpful too. Since I began to do yoga practices, I finally kiss goodbye to insomnia for good.