I refer to Ms Anne Collier's comment that the statement that young children's brains are being harmed by too much use of computers and particularly use of social networking sites is not supported by any evidence.

I think we should be careful about making such sweeping statements. There have been many situations in the past when there was little evidence of harm at the time, but a great suspicion that something was harmful. Later, enough evidence was collected to confirm the original fears. Examples include the effects of smoking, use of hash, too much salt in the diet and the watching of very violent movies by children and late teenagers.

In all these cases our knowledge was initially based on suspicion, but later backed up by hard clinical evidence. There has to be a suspicion before someone starts to collect evidence.

I have a relative who has recently suffered badly from ME and he saw a great number of specialists. All those concerned with brain activity very strongly recommended that he watch no television and make no use of computers until he had at least made some recovery. The reason for this is that the brain uses an awful lot of its energy processing these images. Here I am talking about a 36 year old man who was, prior to his illness, a very fit person, both physically and mentally.

The effects of too much computer use are going to be much higher in young children whose brains are still in the early stages of development.

Do we really want to risk a whole generation of children while we wait for hard evidence to be gathered?

In case people think I am totally against computer usage, I should point out that I use them in my work all the time and when I was teaching, I was the ICT co-ordinator in my school, so I have nothing against them per se. It's just the amount of time young people spend sitting in front of them that worries me.

Getting them away from computers and out into the woods, parks etc is a much better use of their time.