Limbic System The limbic system is the only brain area receiving major hypothalamic input and providing interconnection with widespread cortical areas. Major limbic structures include the amygdala, piriform cortex (parahippocampal gyrus, uncus + amygdala) , hippocampus, substantia innominata, and septal…
Electroencephalography The electroencephalogram (EEG) is a record of the electrical activity of the nerve cells in the brain. The EEG is based on the measurement of electrical fields generated by volume conduction of ionic currents from nerve cells through the…
Surfaces of Cerebrum The cerebrum is divided into right and left hemispheres by a longitudinal fissure. Each hemisphere has three surfaces—superolateral, medial, and inferior—all of which have irregular fissures, or sulci, demarcating convolutions, or gyri. Although there are variations in…
Initial Specification of the Nervous System: The Embryo at 18 Days After fertilization and implantation, the embryo consists of a single cell layer called the inner cell mass. The inner cell mass sits at the bottom of a fluid-filled cavity…