Tertiary sulci are completed during the last month of gestation.
Duration: 6 weeks
Evans OB, Hutchins JB. 1997. Development of the Nervous System. Chapter 5 In: Haines DE, ed. Fundamental Neuroscience. New York: Churchill Livingstone.
Rapid eye movement coordinated response movement.
Duration: 4 weeks
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.