?0 Periodic Table; Effective Nuclear Charge

Brian & Behavior Lecture Notes Week 2 09/13/2016 NEURON DOCTRINE: Cajal considered that neurons were not connected 1. The brain is made up of individual units that contain specialized features such as dendrites, a cell body, and an axon. 2. Neurons are cells 3. Neurons are specialized 4. Nerve fibers are outgrowths of nerve cells. 5. Neurons contact each other through specialized junctions 6. Law of dynamic polarization: There is a preferred direction for transmission from cell to cell (dendrite ­> cell body ­> axon) 7. Unity of transmission: The contact between 2 cells can be either excitatory or inhibitory, but will always be of the same type. 8. Dales’ law: The axon terminal releases a single type of transmitter substance Neuronal Visualization  Golgi (1843­1926) o neuronal staining, impregnated cells with silver nitrate and then reacted to turn black  Ramon & Cajal (around same time): fine structure of cells in the nervous system Neural Net Theory: Golgi interpreted it as not individual neurons, but that neurons were physically connected  Implications for localization & communication (electrical or chemical)  Cajal & Golgi shared the Nobel Prize in 1909  Golgi was not totally wrong, but the dominant way in mammals to study neurons is with the neuron doctrine Major Parts of the Neuron  Dendritic region=input region ­myelin sheath: covers axon Neurons come in different shapes but have the same basic structure/fu