A theory of marks and mind: the effect of notational systems on hominid brain evolution and child development with an emphasis on exchanges between mothers and children.

A model of human language requires a theory of meaningful marks. Humans are the only species who use marks to think. A theory of marks identifies children's scribbles as significant behavior, while hypothesizing the importance of rotational systems to hominid brain evolution. By recognizing the importance of children's scribbles and drawings in developmental terms as well as in evolutionary terms, a marks-based rather than a predominantly speech-based theory of the human brain, language, and consciousness emerges. Combined research in anthropology, primatology, art history, neurology, child development (including research with deaf and blind children), gender studies and literacy suggests the importance of notational systems to human language, revealing the importance of mother/child interactions around marks and sounds to the development of an expressive, communicative, symbolic human brain. An understanding of human language is enriched by identifying marks carved on bone 1.9 million years ago as observational lunar calendar-keeping, pushing proto-literacy back dramatically. Neurologically, children recapitulate the meaningful marks of early hominins when they scribble and draw, reminding us that literacy belongs to humankind's earliest history. Even more than speech, such meaningful marks played - and continue to play - decisive roles in human brain evolution. The hominid brain required a model for integrative, transformative neural transfer. The research strongly suggests that humankind's multiple literacies (art, literature, scientific writing, mathematics and music) depended upon dyadic exchanges between hominid mothers and children, and that this exchange and sharing of visuo-spatial information drove the elaboration of human speech in terms of syntax, grammar and vocabulary. The human brain was spatial before it was linguistic. The child scribbles and draws before it speaks or writes. Children babble and scribble within the first two years of life. Hands and mouths are proximal on the sensory-motor cortex. Gestures accompany speech. Illiterate brains mis-pronounce nonsense sounds. Literate brains do not. Written language (work of the hands) enhances spoken language (work of the mouth). Until brain scans map the neurological links between human gesture, speech and marks in the context of mother/caregiver/child interactions, and research with literate and illiterate brains document even more precisely the long-term differences between these brains, the evolutionary pressure of marks on especially flexible maternal and infant brain tissue that occurred 1.9 million years, radically changing primate brain capabilities, requires an integrated theory of marks and mind.