An international team of researchers has found evidence of this phenomenon in the neural networks associated with reward.
Johannes Frasnelli, a postdoctoral researcher and lecturer at the University of Montreal's Department of Psychology, said that the olfactory - thus non-verbal and non-visual - chemical signals for communication between mother and child are intense.
For their experiment, the researchers presented two groups of 15 women with the odours of others' newborns while the women were subjected to brain imaging tests.
The first group was composed of women who had given birth 3-6 weeks prior to the experiment, and the other group consisted of women who had never given birth. All the women were non-smokers. The odours of the newborns were collected from their pyjamas two days after birth.
Although the women in both groups perceived the odour of newborns with the same intensity, brain imaging showed greater activation in the dopaminergic system of the caudate nucleus of mothers compared to the women who had never given birth.
Located in the centre of the brain, the caudate nucleus is a double structure straddling the thalamus in both hemispheres.
This system reinforces the motivation to act in a certain way because of the pleasure associated with a given behaviour.
Frasnelli said that this circuit makes us desire certain foods and causes addiction to tobacco and other drugs and not all odours trigger this reaction.
The results are published in the September 5, 2013 issue of the journal Frontiers in Psychology.
--ANI (Posted on 25-09-2013)