THE 16-year-old girl who took her life this week in what she described as an ''experiment'' will never know the findings of that test. While the finality of death may play on adult minds, youngsters are less certain about what it really means. ''A dead person will go down to hell and then be born again, this is what the television says,'' said 10-year-old Hung-to during a primary school class discussion on the subject. ''Death means never to wake up again. But my sister told me that a dead person's brainwave will continue to exist in space,'' said Yu-piu, eight, a primary three boy. ''Death means you can no longer see your mum and dad . . . you have lost them, and all your money, too,'' said Ling-ling, aged 10. ''When you are dead, you lose everything . . . your future, family and friends,'' said Fung-ho and Ah Yan, both 10. Perhaps it is this uncertainty coupled with stories gleaned from television and comics that convinces some youngsters they can die more than once. Assistant Director of Education (Services Division), Mrs Grace Yung Leung Yan-mei, who is also a psychologist, says death is a confusing topic for Hongkong children below the age of 11. ''Many comics and Cantonese movies tell of people coming back again [from death] to their friends. This is very confusing for young children,'' she said. ''They think they can start all over again after death, that they might have a chance to come back. For young children, death is reversible.'' The notion that children are unable to grasp the concept of death is further supported by consultant child psychiatrist and senior lecturer in psychiatry at the Chinese University, Dr Wong Chung-kwong. ''They see that [death] is a reversible process, and this cognitive development continues until the age of seven to eight or nine. Of course, some children may acquire maturity earlier than the others,'' he said. DR Wong explained that although some children, as they grow older, begin to see intellectually that death is not reversible, emotionally they remain uncertain. He said children believe death is reversible because they have a tendency to fantasise. ''It's very risky when they fantasise as they don't see death as irreversible or a one-off process. It is a psychological phenomenon,'' he said. Night-school student Jennifer, 17, sees death differently. ''If you are dead, then that is it. I don't believe in spirits,'' she said. Andrew, 15, said he had only thought about death after he lost some relatives. ''You will lose everything when you are dead. But I don't think about death all the time and certainly it is something I don't see happening to me in the near future,'' he said. Mrs Yung said most adolescents, unlike their younger counterparts, know what death means and the consequence of suicide. ''Older children are more able to cope. But sometimes they think their problem is of such magnitude that they think they cannot face it any longer,'' she said. ''Some think their problem is much greater than death. They know about the idea [of suicide] and say 'I might as well die'. There are those who don't have any support from other people and see many people do it [committing suicide]. ''So, it is a combination of all these; the idea of suicide, the curiosity of death and thinking dying might be a way out.'' Dr Wong said that psychologically, children need love, security and acceptance, and those born to an ''abnormal family'' may be deprived of essential psychological needs and develop low self-esteem. There are children who can suffer from psychotic illness such as depression. He said depressive illness is related to the brain function causing an abnormal mood fluctuation not subject to extenal causes, such as a poor family environment. ''But this is a treatable condition and 80 to 90 per cent of these children can be cured,''he said. Dr Wong said that for those children who have emotional difficulties, the right approach was to talk about their problems. ''When a child's emotions are pent-up, when he is not willing to talk to anybody, then this is dangerous.'' Mrs Yung stressed that this applies only to a small group of youngsters who are withdrawn and have little or no support. The majority can cope with their problems. ''At primary [school] age, we have to watch the child's change of mood. Young children cannot hide. You have to be very alert about the symptoms. They may cry a lot or be unable to sleep,'' she said. ''With older children, you cannot detect the tendency towards suicide. They can plan in such a way no one can detect it.'' ''We've asked counsellors to discuss the value of life with students, to let them know that everybody has gone through that period, that problems are not insurmountable and can be solved, and ask them to think of the alternatives and talk to other people.''