10 11 neurons (10 5 per mm 3 ) 10 15 synapses
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1 10 11 neurons (10 5 per mm 3 ) 10 15 synapses
description
10 11 neurons (10 5 per mm 3 ) 10 15 synapses. Electrical signals come IN to dendrites, are “integrated” in cell body, result goes OUT axon. mitral cell (olfactory bulb). motor neuron (spinal cord). dendrite. Pyramidal cell (cortex). cell body. axon. Purkinje cell (cerebellum). - PowerPoint PPT Presentation
Transcript of 10 11 neurons (10 5 per mm 3 ) 10 15 synapses
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1011 neurons
(105 per mm3)
1015 synapses
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From Nicholls et al, 1992, Fisher and Boycott, 1974, Johnston and Wu, 1997
motor neuron (spinal cord)
Purkinje cell (cerebellum)
mitral cell (olfactory bulb)
Pyramidal cell(cortex)
axon
dendrite
cell body
Electrical signals come IN to dendrites, are “integrated” in cell body, result goes OUT axon
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Given sufficient input, neurons “fire action potentials” – fast voltage transients
Johnston and Wu, 1997
INPUT
OUTPUT
DENDRITES
CELL BODY
AXON
Action potential
~100 mV
0 10 msec
Voltage V: set by "excess charge" inside vs outside membrane (more later)
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Given sufficient input, neurons “fire action potentials” – fast voltage transients
Johnston and Wu, 1997
INPUT
OUTPUT
CELL BODY
AXON
0 10 msec
0 10 msec
CHEMICAL SYNAPSE
mV
…which are communicated to downstream neurons via synapses
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FIGURES FROM: THEORETICAL NEUROSCIENCE, Abbott and Dayan, MIT Press
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FIGURES FROM: THEORETICAL NEUROSCIENCE, Abbott and Dayan, MIT Press
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