There are two different ways of remembering things. One is by a deliberate effort of conscious recall while the other can occur involuntarily through the associations produced by sound, smell or bodily sensations. Kristiina Kompus from Umea University in Sweden has been using magnetic resonance imaging (MRI) and electroencaphalography (EEG) to look into the differences between these two types of memory. Conscious recollection was found to involve the upper part of the frontal lobe, whereas unconscious recollection originated in the part of the brain which normally dealt with the sensations that triggered off people's memories. Kompus found that memories did not have to be particularly strong to be activated in this way and that memories recollected spontaneously did not activate the brain more than those recollected deliberately.
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