Each row, column and diagonal of this figure contains pictures that have something in common with each other. I'll give you one of the answers...all 3 neurons in the middle row have square axon terminals. You decide what the 3 neurons in the top row have in common (hint: they are all a type of neuron); what about the bottom row of 3 neurons (hint: they are all another type of neuron)? Try the 3 columns and the 2 diagonals. Think you know them all? If so, check your answers.

Need a bit of help on this puzzle? Try this page on different types of neurons and the synapse.