PSYC 251 Lecture Notes - Lecture 1: Resting Potential, Heinrich Wilhelm Gottfried Von Waldeyer-Hartz, Myelin
22 Jun 2018
School
Department
Course
Professor
1. Foundation: Neurons
o Introduction
History
Denoted structures of brains and connected mind + body –
Santiago Ramon y Cajal (1888)
“Neuron” term – H. W. Waldeyer (1891)
Neurons
100 billion in the brain
Specialized cells for information processing
In PNS and CNS
o Neuronal Structure
Dendrites (INput) -> Cell Body -> Axon (OUTput)
Axon
Axon Hillock -> (Nodes of Ranvier + Myelin Sheath) -> Axon
Terminal
Connections Between Neurons
Synapses
Presynaptic Cell
Synaptic Cleft
Postsynaptic Cell
o Neuronal Signaling
Membrane Potential
Lipid (fatty) bilayer
Prevents flow of ion proteins and other water-soluble
molecules
OUTSIDE (Extracellular side)
Positive
INSIDE (Cytoplasmic side)
Negative
Measured
by Voltage Amplifier and Oscilloscope
Conducts Across Membrane
NonGated Ion Channels
K(+) Channel
Higher electrical potential
Higher K(+) concentration
Electrochemical equilibrium
Electrical Gradient = IN
Concentration Gradient = OUT
Na(+) Channel
Higher electrical potential
Higher Na(+) concentration
