Has it been determined that roller coaster rides and horror films can damage the heart and the brain?

Low risk. The excitement associated with roller coasters and g forces generated can cause neck , brain and heart problems. The risk is estimated to be very low in the range of 1 in 15 millions riders. If a rider has history of any heart, neck or brain condition that's is contraindication to ride. If any rider develop headache, vomiting, dizziness, chest pain, disorientation should be promptly check.