Home • What is Headshaking? • Symptoms & Checklist • Causes • Diagnosis & Treatment • TCM Therapy • Research • Case Reports • Contact

 • Home

 • What is Headshaking?

 • Symptoms & Checklist
 • Causes
 • Diagnose & Therapy
 • Research
 • TCM Therapy
 • Yin & Yang
 • TCM Practise
 • Case Reports
 • Video Clips
 • Products
 • Management of the HSer
 • Content
 • Contact
 • Impressum

Pathways

Neuronal Structure

These pathways are made up of neurons. This image contains real neurons from the thalamus. They have been filled with a fluorescent dye and viewed through a microscope.

The anatomy of a neuron; the cell body (soma), dendrites and axon (marked with text).

At the end of the axon is the terminal, which makes a connection with another neuron.

Note: the axon has been drawn in for clarity, but actually, the axons of these neurons travel to the cerebral cortex.

Neuronal Structure

Impulse Flow

The normal direction of the flow of information (electrical and chemical). An electrical impulse (the action potential) travels down the axon toward the terminal.

Impulse Flow

The terminal makes a connection with the dendrite of neighboring neuron, where it passes on chemical information. The area of connection is called the synapse.

While the synapse between a terminal and a dendrite (shown here) is quite typical, other types of synapses exist as well, for example, a synapse can occur between a terminal and a soma or axon.

The Synapse And Synaptic Neurotransmission

The synapse and the process of chemical neurotransmission. As an electrical impulse arrives at the terminal, it triggers vesicles containing a neurotransmitter, such as dopamine (in blue), to move toward the terminal membrane.

The vesicles fuse with the terminal membrane to release their contents (in this case, dopamine).

Once inside the synaptic cleft (the space between the 2 neurons) the dopamine can bind to specific proteins called dopamine receptors (in pink) on the membrane of a neighboring neuron.

The Process Of Chemical Neurotransmission

Dopamine Neurotransmission And Modulation By Endogenous Opiates

Using dopamine for an example of synaptic function, it is synthesized in the nerve terminal and packaged in vesicles.

Restating the steps in neurotransmission. The vesicle fuses with the membrane and releases dopamine. The dopamine molecules can then bind to a dopamine receptor (in pink). After the dopamine binds, it comes off the receptor and is removed from the synaptic cleft by uptake pumps (also proteins) that reside on the terminal (arrows show the direction of movement).

This process is important because it ensures that not too much dopamine remains in the synaptic cleft at any one time.

There are neighboring neurons that release another compound called a neuromodulator.

Neuromodulators help to enhance or inhibit neurotransmission that is controlled by neurotransmitters such as dopamine.

In this case, the neuromodulator is an endorphin (in red).

Dopamine Neurotransmission

Endorphins bind to opiate receptors (in yellow) which can reside on the post-synaptic cell (shown here) or, in some cases, on the terminals of other neurons (this is not shown so it must be pointed out). The endorphins are destroyed by enzymes rather than removed by uptake pumps.

With permission re-published from the  The Concise Columbia Electronic Encyclopedia © Columbia University Press.

All rights reserved • Copyright © Equis TCM 2009 • Re-publishing or any use with permission only