@Mags well, if you feel you experienced something, I am not going to argue with you.
But- the evidence simply does not support mediums. Anytime that a medium has been tested under proper controlled circumstances, they have failed.
And no one can provide a plausible mechanism by which this supposed link works.Is it telepathy? If so, that means energy is being transmitted direct to the brain of the medium - but no such energy has ever been detected.
And of course, the biggest thing of all - communicating with the dead implies that the dead remain a coherent, separate entity after death -which means that memory and brain function are somehow retain some degree of coherence.This flies in the face of physics. There is no evidence to support this contention at all. Quite the opposite, in fact- most neuroscientists suggest that personality, what makes you you is an emergent property of the unique biochemistry involved in the brain - and when the body dies, thats the end of that.
I suppose it might be possible that there is some aspect of the energy spectrum that we do not yet know about - but that possibility is vanishingly small, and so not really a serious contender.