Tuesday, November 12, 2013

lazy tuesday monocular

spent the last few hours with a patch over one eye. a bit bored and depressed, figured why not?

1. noise, of course. the noise is very interesting, and if i stare at one point for more than a few seconds, strong rivalry begins. the noise is very fine grained, at the limit of resolution, but has strong lower frequency structure, 1cpd or less. it oscillates and swirls, like fine sediment in water or mist when you wave your hand through it. interesting. it gets stronger when looking (with uncovered eye) at something very high contrast.

2. false double vision. if i'm fixating the screen, as now, and bring up a finger in front of my face, it is confusingly not transparent or doubled. yet, it feels as though it is. my left eye, covered, is open all this time, and apparently i have a strong, strong expectation of double vision even when monocular. one thing that keeps happening is that if, as i often do (especially when tired), i start to gaze into the distance behind my screen, a condition where usually the screen would slide into diplopia, i still have the sensation of the diplopia slide, despite having only one eye's view. it's a very strange sensation, of the field sliding while not moving at all. hard to describe.

3. false motion. there's a spot in the eyepatch, about 30 degrees or more above and left of straight ahead, where a bit of light creeps in, so there's a spot there. when i move my eyes around, the spot seems to move back and forth. of course, it's just my eye moving back and forth, but its motion isn't being 'cancelled' in the same way as motion in the uncovered eye, i.e. saccadic suppression doesn't seem to be working over there.

the noisy view from the covered eye is different between fovea and periphery. it's similar to what i've described in other entries about the intrinsic light, how it seems clustered and of a different brightness - even opposite polarity - than the surround.

at times the noise is overwhelming, especially when fixating - it mixes and almost seems to average together with the scene. i'm going to go home now, see if i can keep this up while walking around outside.

trip home was uneventful, just uncomfortable. i was wondering if i'd get sick on the train, but nothing like that; instead, the constricted visual field, and noisy monocularity of the remaining field, made everything seem closed in, like the whole world was crammed into my face. not sure i can chalk that up to loss of depth perception, but it was in a way a much smaller, flatter world. claustrophobic.

when i got home, i took off the eyepatch while looking at jingping, to see if she'd notice anything odd. for the first second or so, i couldn't fuse the scene, but then it came together. still, there was an uneasy feeling that i was going to lose fusion, and i even tried to provoke it, but everything stayed together. the contrast aftereffect was surprisingly minor; the luminance aftereffect (it was dark under the patch) was more sustained.

Thursday, November 07, 2013

vision and light

top 10 total disconnects between light and vision

1. symmetric encoding of more versus less flux. actually, more neural response to darkness than brightness. neural silence is encoded as a neutral gray. so, a domain of natural numbers, i.e. numbers of photons, is mapped to a U-shaped function of neural response. no, not even a U-shaped function. see Whittle.

2. nonsensical encoding of the EM spectrum. the visible spectrum, continuous linear change in photon energy, wrapped around in a circle? red next to blue? clearly no idea.

3. color constancy and the Adelson illusion.

4. mach bands and phosphenes don't count. these are reasonable side-effects of having a system processing things. you can see the corners of the system, or you can bump it around. no harm here.

i am taking suggestions:::

Sunday, November 03, 2013


okay, that last thing was a little embarrassing. i'm going to leave it there as punishment, and also because i keep deleting entries and it's a bad habit. why do something you're just going to cancel out? i'm not some buddhist monk drawing sand mandalas. need to be a bit more selective. always the problem. this one's getting embarrassing too, be careful!

okay, nearly done with the applications. why is it taking so long? losing enthusiasm, i guess. excited at first, not anymore. considering other options.

not much else. paper stasis, no new data lately. just wanted to push that halloween poem off the top. mission accomplished.