Fetal movement and touch (self-cognition)
Fetal movement begins spontaneously in week 7 to 8 after conception. Not only does it involve movement of the entire body, but beginning with finger-sucking, these movements appear to be combinations of various movements to touch one's face, head or all over the body, At this stage, the fetus, which is an embryo, is not yet considered to have a functioning cerebrum. How then can we explain the fact that these movements begin at this stage?
The team headed by Professor Yasuo Kuniyoshi at the Graduate School of Information Science and Technology, The University of Tokyo has been researching the simulation of fetal movement. They have boldly hypothesized that these movements are responsible for the creation of the brain. In other words, self-cognition of the body is the result of movement produced by central pattern generators (CPGs) in the spinal cord through the action of the hands touching the mouth or face.
Moreover, the fetus becomes aware of its arms and legs through the sensation of pressure that is generated during movement in the amniotic fluid. This is also similar to the views of developmental physiologist, Dr. Philippe Rochat. In other words, the body is mapped in the brain through spontaneous bodily movement and touching. Books on physiology invariably show a somatotopic map that was first conceived by Wilder Penfield and most are in the form of a homunculus, a small representation of a human form. The hypothesis of Professor Kuniyoshi's research team challenges our notions of how and when such mapping is inscribed.
On the other hand, it appears that the human baby is capable of self-cognition of the body at the fetal stage. This can be ascertained by the fact that newborns already have a sense of balance that enables them to adjust to gravity. For example, when held at an angle, they will raise their head in the opposite direction as a counterbalance or they turn their head in the direction of a sound or light or extend a hand to something in front of them. This indicates that the fetus apprehends its own body at this stage and the sense of touch is thought to be an important sense in attaining this capability. It appears that among the so-called five senses, the sense of touch begins to function the earliest, first with touching in the mouth area and then the fingers. Given that sight and hearing do not begin functioning until week 24 or 25, it can be definitively said that when the fetus moves, it relies on touching for a period of 16-17 weeks or more than 100 days.
Sense of Sight in Newborns
Although finger-sucking and other hand-body touching is prevalent in the fetal stage, however, this behavior is not seen in infants until some time after birth. Infants begin finger-sucking two months after birth. They bring their hands together four months after birth and touch their feet five months after birth. In the fetus, this touching starts with the head and mouth, moving gradually to the shoulders and body, and finally to the feet just prior to birth. The same tendency is also seen in newborns, however, at this time, newborns appear to be confirming their bodies with the added senses of sight. When 3-month old infants are shown images of their feet, one from the direction in which they always view their feet and the other from the direction of the feet, they look longer at image shown from the direction of the feet. This seems to indicate that a 3-month old infant visually recognizes his or her body. In fact, it appears that the infant is visually reconfirming the body that was first perceived through touch.
This phenomenon could even apply to the perception of objects. That is, the infant first perceives the shape and weight, etc., of objects, through the physical sensations, including touch. Newborns are, of course, incapable of stereoscopic vision at birth, and must therefore grasp the nature of things, etc., with their hands and mouth, and then later perceive them visually as well. At that time, what is important is movement, in other words, that the cognition of objects is further facilitated by functional movement. In fact, according to Yoshiaki Iwamura's work, what was called the sense of touch in Aristotle's time also meant "to touch." Today, this would be called something similar to active touching, an important subject of current research. The shape or weight of an object cannot be perceived by looking alone--this requires touching and picking it up. This means that movement and functional use of the sense of touch is necessary for cognition. Of course, the other senses also have active and passive sensory input, but until quite recently, most research has focused on passive sensations with very little research devoted to active sensation. Nevertheless, grasping and touching and other such behaviors are very important exploratory activities for infants. It is widely accepted that actively touching an object is better than passive touching, and active touching has become an important research topic in physiology and psychology.
In Child-Care and Child-Raising Practice
Perhaps due to the influence of such a research trend, many books on child raising and child care stress the importance of sensory input through visual and auditory stimulation of neonates and infants in the practice of childcare and daycare. As for touching, for example, they encourage "skinship" in the form of "touch care" and "baby-massage." Very few of these materials address active sensory input, a fact which I find quite disconcerting. Infants spontaneously explore and perceive their surroundings through sight, touch and other senses. Such repetition produces cognitive abilities. Nevertheless, in the practice of day care or child raising, the infant is often stopped from touching or putting something in his or her mouth for safety reasons. Told that it is dirty or dangerous, licking and chewing also tend to be forbidden during this crucial exploratory period.
Considering that finger-sucking occurs in the fetal stage, it can be said that for the fetus, the mouth is the "self." The hypothesis that the fetus perceives its hand by inserting it in the mouth and then perceives the body with this hand is not altogether mistaken. This would indicate that instead of adults repeatedly touching infants and children, it is more important for children to engage in active touching and mimicking.
There is an interesting comparison of the visual and auditory in a book by a person who became visually handicapped later in life. Compared with sight that tends to passively receive rapidly processed information, touching slowly feels its object and carefully explores it. When seeing people are masked and engage in touching, they are often delighted by the perception of a very different world. Rather than seeing and hearing which require simultaneous processing and assessment of input information, we need to pay more attention to and reconsider the slow and careful discerning sense of touch.
Finally, the research of my collaborator, Dr. Satoko Ito, a pediatrician, confirms that when an infant is being breastfed, it also gently touches the mother's breast with the palm of the hand. When mothers are asked about this at various lecture events, a number of them remember being touched, but when asked whether it was the palm or back of the hand, almost none are able to answer correctly. In other words, they remember what they did, but not what the infant did for them. This suggests the time has come to reevaluate active sensory input, including the fact that the majority of the interaction between mother and child originates from infant.
