No matter what anyone tells you, it’s not a “spider.”  It’s a neuron.

Borrowed from Coastal Carolina University’s website.
http://ww2.coastal.edu/kingw/psyc415/html/neuron.html

I found this image and decided it was one of the best for my needs.  We’ll be referring to this often when it comes to discussing drug treatments for bipolar disorder, because my group (I do love them) opted to go for the more “sciency” approach and had the psychiatrist talk us through how the actually work, and I took a lot of notes.

If you’re not interested in getting a grounding in brain chemistry and how neurons talk to each other, you can skip over those posts and just read the handouts.  🙂

For the moment, what you need to know is that tree looking thing on the left is actually repeated on the right, but you can only see the edge of it.  Same goes for the other side.  Think of it like a big daisy chain, this thing is repeated over and over again but you can only see the edges of the repeat.

Anyway, that big bit is the dendron, the little hairy bits coming off it are dendrites, the long tail is the axon, and most importantly for us… that inset is a closer look at the synapse.

You can kind of see that they were trying to show that it is a ‘lock and key’ kind of functionality, where receptors will only accept certain kinds of neurotransmitters.  I think of it like Tetris.  😛

My games of Tetris never go this well. =P
(http://tetrisaxis.nintendo.com/)