My cat has developed a fear of noise and retreats to the basement with even the slightest movement such as the russling of the trees. This occurred after a violent thunder storm about 2 weeks ago. Suddenly, he is petrified of being upstairs. He will come up a few times a day for about a minute when sometime will scare him (like a car driving past the house) and he will instantly run to the basement. Yet, when we are downstairs, he is not afraid and begs for our attention. HELP!