THE picture imprinted my mind is that of a dark haired mother in a overcoat running through the gates of the school at Dunblane. It was the red coat that stood out. Just as the red coat of the little girl in Schindler's List was contrasted against the monochrome background of horror.

Every parent watching the on television knew what was on the young mother's mind. She was rushing to find out if her child was alive The thought which crossed my mind and, I'm sure of every parent watching, was: "God. Imagine if it had been one of mine." In that moment the anguish of the parents of Dunblane was shared by millions.

But our anguish, the tears which were brought to our eyes, were shortlived. The grief of those directly affected by the actions of a seriously deranged man will last for years.

Most of us know how the feel. Even those of us whose are much older than the little ones who were massacred will admit that when we look in the eyes of the young adults who are our offspring, there is always a moment when we see them as the innocent toddlers they once were.

Think of the children who survived children of an age at which a feeling of security is a prime emotion and to whom home and school, with their caring adults, are the very bastions of the security they so strongly desire.

Almost exactly two years ago, at the Hall Garth School, in Middlesbrough, Yorkshire, a masked man entered a classroom and stabbed 12 year old Nichola Conroy to death. Some of the children who witnessed the murder are still receiving psychological treatment.

Dr Michael Wright, occupational health co ordinator at Cleveland County Council, who organised counselling for those involved in the Middlesbrough outrage, has no illusions about the long term effects.

SOME will survive emotionally but no one who was in the classroom on that day ever get over it. "It is not a case of getting over it. People who live through that are always going to remember that it happened. They will still be talking about it when they are 90," he said.

At present some of the Middlesbrough children suffer from sleep disturbances and nightmares. For others, the after effects are more distressing. They have flashbacks to the horrific event, triggered by the ordinary events of everyday life.

"For some children, it might be the fire alarm or the sound of adult voices shouting or of running feet, which act as the trigger," Dr Wright said.

In Middlesbrough some of the children at the time thought: "We are all going to die". Others had the innocent childish feeling that as long as they did what they were told they would not be hurt.

The Middlesbrough children were considerably older than the victims of yesterday's tragedy, but that feeling of being all right if they did what teacher said must surely have been in their minds.

What was in the mind of Thomas Hamilton as he walked into the school gymnasium yesterday morning is another matter.

The long series of mass killings in recent years has given psychiatrists some inkling of the workings of the minds of people who commit such outrages. Dr Clive Meux, a consultant psychiatrist at Broadmoor Hospital, says that tragedies of the type of Dunblane, Hungerford and others have been split into three broad groups: mass murders, spree killings and serial killings.

AT Hungerford, 10 years ago, Michael Ryan killed his victims in more than one place. That, Dr Meux said, was categorised as a spree killing.

At Dunblane, the killer appeared to have shot all his victims in one place. What happened there, he said, falls into the category of "mass murder".

The killings are further divided into three sub groups, and Dr Meux stressed that Thomas Hamilton need not necessarily have been insane to have committed the acts which ended the lives of himself and his 17 victims, and ruined the lives of so many others.

One type of killer he described as the "pseudo commando", usually a young man obsessed with firearms the second group comprises psychotic killers who are generally mentally ill, but not necessarily so and thirdly, there are the "set and run" killers who plan their murders with some deliberations.

Another psychiatrist, Prof Peter McGuffin, of the University of Wales, also warned against people assuming that the killings were necessarily the work of a madman.

A recurring theme in statements from people who knew Hamilton is that they were aware there something wrong with him. They could not give a coherent reason this. To them there was just a gut feeling that there was something wrong with the man. The feeling many of us have experienced unexpectedly in the presence of certain people.

Hamilton's activities in running unauthorised boys' clubs, his photographing of young boys in swimming trunks and his pasting of those photographs around his house, were certainly signs of a personality problem but not necessarily an indication that he would rampage through a class of young children.

His obsession with firearms is another matter and certainly put him in a category similar to those who have committed mass murders in the past.

He may have displaced his feelings, according to Dr Meux. He may have put his problems into a place where they had no real relevance, such as the gymnasium at Dunblane Primary School, where his boys' club once met.

Hamilton's mental problems have come to an end. The trauma, for others, has just begun.