It is worth looking at one or two aspects of the way a mother behaves towards her baby. The usual fondling, cuddling and cleaning require little【A21】______, but the position in which she holds the baby【A22】______ her body when resting is rather【A23】______. Careful American studies have disclosed the fact that 80 percent of mothers【A24】______ their infants in their left arms, holding them against the left side of their bodies. If【A25】______ to explain the significance of this preference, most people reply that it is obviously the result of the【A26】______ of right-handedness in the population. 【A27】______ holding the babies in their left arms, the mothers【A28】______their dominant arm free for manipulations. But a detailed analysis shows that this is not the 【A29】______. True, there is a slight difference between right- handed and left-handed females, but not【A30】______ to provide an adequate explanation. It 【A31】______ that 83 per cent of right-handed mothers hold the baby on the left side, but then 【A32】______ do 78 percent of left-handed mothers.

The only other【A33】______ comes from the fact that the heart is on the left side of the mother’s body. Could it be that the sound of her heartbeat is the vital factor? And in what way? Thinking along these【A34】______ it was argued that perhaps during its existence inside the body of the mother, the 【A35】______ embryo becomes fixated【A36】______ the sound of the heartbeat. If this is so, then the re- discovery of this 【A37】______ sound after birth might have a calming【A38】______ on the infant, especially as it has just been【A39】______ into a strange and frighteningly new world outside. If this is so then the mother, either【A40】______ or by an unconscious series of trials and errors, would soon arrive at the discovery that her baby is more at peace if held on the left against her heart, than on the right.