According to these theories, the concept of time depends on the spatial reference frame of the observer, and the human perception, as well as the measurement by instruments such as clocks, are different for observers in relative motion. For example, if a spaceship carrying a clock flies through space at (very nearly) the speed of light, its crew does not notice a change in the speed of time on board their vessel because everything traveling at the same speed slows down at the same rate (including the clock, the crews thought processes, and the functions of their bodies). However, to a stationary observer watching the spaceship fly by, the spaceship appears flattened in the direction it is traveling and the clock on board the spaceship appears to move very slowly. On the other hand, the crew on board the spaceship also perceives the observer as slowed down and flattened along the spaceships direction of travel, because both are moving at very nearly the speed of light relative to each other. Because the outside universe appears flattened to the spaceship, the crew perceives themselves as quickly traveling between regions of space that (to the stationary observer) are many light years apart. This is reconciled by the fact that the crews perception of time is different from the stationary observers; what seems like seconds to the crew might be hundreds of years to the stationary observer.
A Mayo Clinic report indicates: "Comprehensive medical and neurological examinations in children diagnosed with childhood disintegrative disorder seldom uncover an underlying medical or neurological cause. Although the occurrence of epilepsy is higher in children with childhood disintegrative disorder, experts dont know whether epilepsy plays a role in causing the disorder. "CDD, especially in cases of later age of onset, has also been associated with certain other conditions, particularly the following:
Lipid storage diseases: In this condition, a toxic buildup of excess fats (lipids) takes place in the brain and nervous system. Subacute sclerosing panencephalitis: Chronic infection of the brain by a form of the measles virus causes subacute sclerosing panencephalitis. This condition leads to brain inflammation and the death of nerve cells. Tuberous sclerosis (TSC): TSC is a genetic disorder. In this disorder, tumors may grow in the brain and other vital organs like kidneys, heart, eyes, lungs, and skin. In this condition, noncancerous (benign) tumors, hamartomas, grow in the brain. Leukodystrophy: In this condition, the myelin sheath does not develop in a normal way, causing white matter in the brain to eventually fail and disintegrate. Treatment
Loss of language and skills related to social interaction and self-care are serious. The affected children face ongoing disabilities in certain areas and require long-term care. Treatment of CDD involves both behavior therapy, environmental therapy and medications. Behavior therapy: Applied Behavior Analysis (ABA) is considered to be the most effective form of treatment for Autism spectrum disorders by the American Academy of Pediatrics.