I've no idea what "open field or EPM" are, but you may be making the same mistake I made some years ago, namely confusing stress and anxiety.
When I first learned about stress, the prof discussed how there was an optimum level, beyond which performance deteriorated. He discussed this using an inverted U graph. Someone asked what happened at the origin, where stress was zero. I'll never forget his reply, namely, "You're dead."
Later I asked another prof, who was discussing anxiety, about an optimum level of anxiety. Puzzled, she said that the optimum level of anxiety was zero.
Some stress is good, up to a point. In no situation is anxiety good.
Health is wealth & to keep & maintain good health depends only on us as while keeping good health , it also helps our destiny for getting success in our planning program .This keeps our health care under our will power & faith within us & if we keep & maintain the same standard action for the life our health becomes our temple .
With this psychiatric anxiety only rest with the individual .Our will power keeps the challenge for the life which may certainly help to challenge the problem of the life .A will power withthe prayer & silence sitting for ten minutes both in the morning & sleeping time may help certainly to solve the problem of our life including even the disturbance of our health .