PS263 Chapter Notes - Chapter 3: Central Canal, Binding Problem, Choroid Plexus
Document Summary
Nervous system begins development as a tube surrounding a fluid canal that persists into adulthood as the central canal and ventricles. Central canal: fluid filled channel in centre of spinal cord. Ventricles: four fluid filled cavities within brain, choroid plexus cells inside ventricles produce cerebrospinal fluid similar to blood plasma. Cerebrospinal fluid cushions brain against mechanical shock when head moves and provides buoyancy, helps support weight of the brain and provides reservoir of hormones and nuitrition for brain and spinal cord. Cells on outer surface are gray matter, axons extending inward are white matter. Neurons in each hemisphere communicate to corresponding part of other hemisphere through corpus callosum (2 bundles of axons) and anterior commissure. Primates (monkeys, apes, humans( have larger cerebral cortex, more folding, and more neuron volume. Cerebellum occupies around 13% of any mammalian brain. Consists of up to 6 aminae/layers of cell bodies parallel to surface of cortex, separated by layers of fibres.
