How familiarisation breeds contempt
How do we learn to recognise new sensations and distinguish them from those we are already familiar with? Research with mice shows that it may be to do with new nerve cells growing in the spine.
We are constantly exposed to everyday touch stimuli, such as walking on grass or shaking hands, but take little notice. However, an insect crawling on our hand will produce a much greater response. This is vital to filtering out every day sensations allowing our body to focus on the important signals in our environment.
To understand this process, researchers put mice in unusual touch environments, such as cages containing sandpaper, gravel or sponge. They found that mice exposed to unusual touch environments produced more nerve cells initially, but then nerve cell production fell.
This may explain how we become familarised to everyday touch stimuli. The findings could be applied in the treatment of pain and may help to explain how ‘healing hands' may work in alternative medicine.
Similar results have been observed in relation to our sense of smell. This suggests that the process of increased neurone production could be how sense organs first learn to recognise new sensory-signals and distinguish them from the everyday background sensations and then learn to take them for granted.