 During the studys 20-week duration, all children will receive Hyperbaric Oxygen Treatment HBOT for two eight-week sessions, with a four week session between. Therefore, all children will participate in the study for 20 weeks, and will receive HBOT for 16 weeks. This is an open label study. This means that there will not be a placebo group in the study. All study participants will receive the same treatment of HBOT in a hard shell chamber. Normal air contains about 24 oxygen at a pressure of about 1 atmosphere absolute ATA. The chamber will contain 100 percent oxygen at a pressure of 1.5 ATA, which is equivalent to the pressure at a depth of 15 feet in sea water. Each subject will complete the first 40 treatments during one hour sessions on 5 separate days in each of the first 8 weeks. They will then take a 4-week break before they begin their next 40 treatments, which will also occur during one hour sessions on 5 separate days in each of the last 8 weeks. The entire study will last 20 weeks. The childs behavior will be measured and evaluated at the MIND Institute at the beginning of the study, at week 8, and at week 20. 