And this is the vision lab:
And this is the bite-bar setup (where the observer sits):
Yesterday was pretty neat because I got to learn how to use the Maxwellian system and collect some data on Armando. I was a bit nervous at first because I wanted to be perfectly sure about what buttons to press and when, that sort of thing, because that data will be used in our experiment. The data on me yesterday was just pilot data, meaning that it was only taken to get us familiar with the setup and to make sure everything is in working order.
The machine is pretty simple to use, although it can do other, potentially more interesting things than what we’ll be using it for. After turning the system on, you have to turn on the computer and run the program that allows you to input the values that are used to generate the stimulus. But before doing any of that, the observer (the person on the bite-bar and who will be looking at the stimuli) has to ensure that he’s properly aligned with the system.
Then the proper filter must be in place in the system, otherwise the bleaching step won’t work. The person has to initially adapt to the dark for 10 minutes; all the lights aside from the computer monitor and a flashlight (with a red beam) are turned off, and big pieces of black cloth and cardboard cover up any of the light that could potentially reach the observer. Once 10 minutes have elapsed, the person gets in position in front of the viewing window and gets bleached – a hella bright light is shone on their eye for 10 seconds. This hurts, fyi, but doesn’t do permanent damage :oB
As a little background info, the cells in your eyes that send off information to your brain about the light that they detect contain components that break apart when light is presented to them. It takes time for the components to be put back together, and when someone adapts to the dark and then gets the flood of bright light, all of the cells in the area of the retina exposed to the light must, basically, get recalibrated. Thus, we can measure differences in the perception of stimuli based on the time it takes the person to re-adapt to the dark. Stimuli are presented at 1 minute and at 4 minutes after bleaching, then again at 4 minute intervals until 28 minutes have elapsed. This is repeated twice in one session.
The stimuli we’re concerned with aren’t very exciting...they’re just small circles of color presented directly to the observer’s retina. The observer fixates his gaze onto a focal point, and after the stimulus is presented to the left of the focal point, he has to describe the color (in terms of hue and saturation). The experimenter writes the responses down, sets up the next stimulus, and waits until it’s time to present it.
Yeah, not the most stimulating research out there, but I think it’s cool, even if I don’t really understand how the Maxwellian system in the lab works~ The sessions are pretty boring (taking about 1.5 hours each), especially because you’re in the dark the whole time, but it’s made tolerable because you get all chit-chatty with the other person in the room.
Today, Armando ran me on the system in the morning. At 1:00 I had to attend a seminar on basic research methods, which was quite a snoozer because I’ve taken a whole class on that stuff, plus I’ve done research already, so I knew the drill. At 2:00, my peeps and I built a very crude Maxwellian system, from this:
to this:
That was really fun, mainly because I enjoy putting stuff together. We put in some colored filters and a prism that enabled us to combine lights, giving us somewhat of an idea of how the big system works in the lab. Finally, we got to take off the cardboard that was on the lab machine and take a gander at its inner-workings; I’m still amazed by the fact that we need so much expensive junk just to do something incredibly simple, but that’s neither here nor there :o)
Sidenote: While I was taking photos today, Vicki asked me if I wanted her to take my picture, or if I wanted to take pictures of them. The thought never occurred to me because I was mainly concerned with showing off the lab and the equipment, neglecting to assume that you guys would also like to see the folks I'm working with. I also thought it would be rude to take their pictures, though, since I barely know them, but I might sneak some shots of them later on.