sub-zero neuron tracing

it is cold in toronto. i'm not complaining, but merely informing you that it hurts to be outside right now. of course, this snap has timed itself perfectly for the one month in which i need to spend more time than usual walking around out of doors. i'm in the last stretch of an experiment that i started back in november, and this particular phase involves using a microscope located at the Toronto Western Hospital. my lab is at a different hospital, about a 12 minute walk from where the microscope is. unfortunately, those 12 minutes are not in the direction of my house, but further away from my house. this means that every morning i have to spend 32 minutes walking to work instead of 20, and then there are one or two 24 minute return trips to the lab squished in over the day. i have broken out the long johns.

incidentally, i still wear the same long johns that i've had since elementary school. somehow they wield a miraculous power of stretch, while maintaining consistent warm-and-cosiness.

anyways, for the past couple of weeks i have been tracing neurons. apart from eating, this is how i kept myself busy while in India last winter (as described here). in fact, the reason that i was sent to India in the first place was to learn a method of staining tissue called Golgi-Cox impregnation. this Golgi Staining allows you to visualize single neurons in a thick section of brain tissue. then, with fancy computer software and a microscope, you can trace the outline of the neuron's body (called the soma in this context) and all of its arms and legs (called dendrites). you end up with something that looks like this:


then, with the fancy computer software, i can determine how long the arms and legs are and how big the cell body is. i might also get excited and look at how complicated the network of arms and legs is. some neurons will have only one or two arms, while others will have many. this tells us a bit about how active the cell might have been while it was still alive - a neuron with fewer arms would make fewer points of contact with other neurons, while a neuron with plenty of arms and legs would probably have been heavily connected to other neurons.

because they're so pretty, here's one more before i brave the cold: