The Postnatal Development of the Human Cerebral Cortex. Volume III; The Cortex of the Three-Month Infant

This is the third volume of Dr. Conel's unique monographic series which extends his meticulous microscopic study of the development of the human cortex to three months of age. It presents in detail the histologic criteria of development by which comparison may be made of brains of the same or different ages or of various areas within the cortex of one brain. The criteria are: 1. width of entire cortex and of each horizontal layer; 2. number of cells; 3. size of nerve cells; 4. condition of the chromophil substance ; 5. neurofibrils ; 6. size, compactness of structure (including varicosities), and length of processes of nerve cells; 7. pedunculated bulbs; 8. size and quantiy of exogenous fibers; and 9, state of myelination. The manifestations of growth and development of the cerebral cortex by these criteria correlate with observations on the progression of voluntary activity in infants.