At approximately day 1

Central canal of spinal cord is present.

Duration: 1 week

Reference

Moore KL, Persaud TVN. 1998. The Developing Human: Clinically Oriented Embryology. 6th ed. Philadelphia: WB Saunders Co.

At approximately day 1

Isolated head and limb movements.

Duration: 3 weeks

Reference

DiPietro JA. 2001. Fetal neurobehavioral assessment. In: Singer LT, Zeskind PS, eds. Biobehavioral assessment of the infant. New York: The Guilford Press. p 43-80. Citing Als, H. 1982. Toward a synactive theory of development: Promise for the assessment and support of infant individuality. Infant Mental Health J 3:229-243.

At approximately day 7

Corpus callosum appears.

Reference

Moore KL, Persaud TVN. 1998. The Developing Human: Clinically Oriented Embryology. 6th ed. Philadelphia: WB Saunders Co.