endojan

it's the end of january, so why not throw in another entry?

i revamped my priority ranking system yesterday, surprisingly quickly, in the form of a matlab script (the spreadsheet had gotten too complicated, as tasks were completed and added and modified..). right away it showed me that i should do one small job that i had been putting off for months, and so i did it.

it's kind of sad how by forcing structure on my life in such a simple way - write a computer program to sort out a list of the things i have to do - it immediately becomes undeniable that i have to do something. without this little trick, i am apparently lost in a haze, unable to see what is right in front of me. i suspect it is because i am hiding things from myself, and i still do not understand why.

also, tuesday afternoon, i was smacked with an idea and sat down and wrote a story. i satisfied a secret desire today by sending it in to the Nature Futures series. of course, i'm sure a hundred people do this every day, but i couldn't think of a reason not to attempt it - and i decided not to go through a dozen rounds of revising the story, showing it to friends, etc. etc., just because it's so nice not to have to do that for once. anyways, when it's rejected, i'll put it here so we can have it all to ourselves, won't that be nice?

enough. it's time for february.

TKD CSD

So, 4 days ago I dreamed of seeing a scintillating scotoma, and then became vaguely paranoid of how inconvenient it would be to have one on Sunday morning before my black belt test; then, today, after I'm home from the test and from grocery shopping, I for some reason start a conversation with j* about how migraines can be associated with relaxation after stress, and tell her the story of VanValkenburgh's Vacation; and this afternoon, coming in with the groceries, i get distracted for a little while by a foveal afterimage, probably from the sun glinting off a car windshield - but maybe it was something else. Yesterday, or a couple of days ago, I was distracted for maybe a minute by the noisiness of my visual field, having momentarily noticed how snowy everything looked. I think that was Friday...

So finally, about 9pm tonight, in the kitchen about to explain to j* why my shoulder hurts (because I briefly dislocated it by swinging my arm wildly at an odd angle towards an 18-year old), I realize that my foveal vision feels scotoma-like (if there is a word for 'feels like a scotoma', I don't know what it is. Specific feels, like 'rough', or 'bright', or 'salty', have specific, ancient, singular morphemes attached to them, so it's hard to invent a new word for a new feeling, or for one that is rare or obscure enough that it hasn't been named). I pick up a knife and start trying to use the sharp tip, at arm's length, to find a blind spot, but can't find it; the start is always odd, since I think the scotoma is very small and maybe discontinuous, and maybe even not binocular. For whatever reason, I can tell that it's there, but it's often hard to find. Then, as I've mentioned many times here, it seems to disappear; then it reappears.

This one was right field; headache is very slight, I felt it start midway through the aura, as a little jolt of pain, then disappeared. I have to shake my head to feel it; possibly would be a little worse if I hadn't taken an ibuprofen soon after the scotoma was after, though I took it for my shoulder...

So I got another recording with scotmap, which I think is good, but all my code from last summer is written implicitly for a left-field scotoma, and my code is complicated and uncommented, so it will take me a little while to straighten it out and make another good animation to post up here. I do have the data transformed and fitted to the wave model I came up with, and the result is very similar to the last measurement: exactly 3mm/min, starting a few millimeters on the V2 side of the inferior V1/V2 border, 10 or so millimeters from the foveal confluence. This is consistent with my feeling that there is a scotoma, and yet being unable to see it directly; the scotoma begins in V2.

There's something weird at the end, a bunch of data at a much smaller eccentricity; this may be an error, I don't think it's the 'rough spot' that I have mentioned before. Will work it out this week.

Meanwhile, here's a general migraine data plot, relating my estimates of headache intensity on a 10-point scale (notice what a fortunate migraineur I am) to the time elapsed since the previous headache. Most of these ratings are retrospective, based on these journal entries. I see a relationship: more frequent means more intense. The outlier at zero is the night in China last month, where there was no headache at all, which I attributed to the simultaneous alcohol intake with the aura.


In other news, I have failed to make progress this weekend on E*'s presentation.

Also, saw a nice show at the BSO last night: Hindemith, Liszt, and Prokofiev.

year

briefly, because we don't want to dwell on this:

what did we accomplish last year? what did we intend to accomplish?

1a. submitted a fellowship proposal, which was rejected
1b. submitted an R01 proposal, which will be reviewed in 2 weeks (and likely rejected)
3a. submitted 2.5 papers, one published (so we are not zero for 2012), one more accepted, one heavily revised (if all goes well, should be 3+ for 2013)
3b. wrote the classification spectrum paper that is in a holding pattern
4a. completed a binocular rivalry experiment that will make a paper someday, and learned to model binocular rivalry
4b. started a new and improved blur adaptation experiment that is interesting
4c. created a model of my visual cortex that can be fit to my migraine auras
5. wrote a lot in HAZ public journal
6. applied for my first real job
7. learned 14/15 of the bach inventions (9 or 10 of which i didn't already know)
8. trained for my black belt in tkd (testing soon) without getting seriously hurt
9. settled on some new ways of organizing my work (subversion, dropbox, zotero etc etc)

what for this year?
1. find a new job
2a. finally publish the blur adapt paper
2b. submit/publish the classification spectrum paper
2c. write and submit the rivalry paper (short and model-free)
2d. present the new adaptation work and write a paper
3a. learn at least half of the bach sinfonias
3b. learn to sing and play piano at the same time
4a. continue with the journal entries, get back to work-related, less of the self-stuff
4b. start writing journal entries in chinese with some regularity
5a. do the computational experiment in the R01 proposal, funded or not
5b. find somebody to collaborate with on something... hm...
5c. plan some new experiments beyond the proposal stuff

dream aura 2

dreamed last night that a scintillating scotoma was starting; i think i was trying to read, but couldn't see letters, space was distorted as though there were blind spots. i'm wondering if now that i'm familiar with the scotoma experience, the normal dream experience of being unable to resolve text in a dream is now naturally triggering thoughts, and ensuing dream experience, of a migraine aura.

i went to get my laptop so i could start recording the aura, but then i got distracted by downloading a video game, which then autonomously tried to download other games, which made it impossible for me to get back to matlab to run the aura recorder.

after a few minutes, i realized that either i had missed the whole thing, or it had stopped, because there was no scotoma and i couldn't remember seeing any of the big peripheral scintillations. at some point after that, i realized it had all been a dream, and i started wondering whether i actually had a headache or not; then i awoke, and went through the same train of thought again. but happily, no headache.

my tkd black belt test is sunday, and i am slightly nervous that i will get a headache sunday morning; i have a superstitious feeling that i have *caused* the headaches before by thinking too much about being about to have one, when in fact i think i've just subconsciously noticed aspects of prodrome. anyways.

gone, gone..

I need to get back to posting on my research activities, which have not ceased completely believe it or not. Next time, next time.

My grandfather, granddaddy, RSM, died Tuesday night. He was 92, born on the Ides of March in 1920. He was my last grandparent, my mother's father. Her mother, Elizabeth, who I will always say was probably the most important influence on the development of the contents of my mind, died almost 3 years ago at 85. My father's father died in summer of 2001, 89 years old. His mother died in 1998, 84.

My mother's parents were always closer to us, maybe because they were younger than my father's - by a decade - and had a lot more energy left. My father's parents could only tell me stories and talk with me; my mother's parents took me places and taught me things.

Elizabeth gave me books, told me about what she knew and where she'd been, took me to museums and historical sites all over the southeast, taught me to explore cities and the countryside and new towns, and to wonder where we and our ancestors had come from, and where all people and their cities and their civilizations had come from.

Granddaddy took me fishing on the rivers and lakes that he'd fished on since he was a boy - since before they had existed, in the case of those big TVA lakes, I guess. He tried to take me hunting, but I clearly wasn't interested. He took me camping and exploring in forests and mountains. He showed me how to interact with nature, and I don't think he ever knew how much of it stuck with me. I'm not a fisherman, but I know how to fish, and I know how to get around in the woods, and I'm at home in the outdoors. He was also a doctor and an artist. On the outside he was a cynic and a skeptic as pertained to human things, but he was always fascinated with nature, and with the human being and the human mind, and I think he was proud of me for becoming what I am. I know for certain that since I was little I learned to copy his personality, and my mother has commented on it positively and negatively, because he could be harsh and negative. I always wanted to be like him.

It was so strange to see him go, just like it was with Elizabeth, who was always so mobile and active and who spent her last year or so unable to get out of bed. Granddaddy, and I told him this the last time I saw him, was always the strongest person I ever knew, the model of strength, invincible even though I knew he was always getting injured in one way or another, always sick but always too strong for the sickness. But in his last years he lost his house and all of his health, and became thin and pale and weak, and finally he too was stuck in bed, but thankfully only for the last couple of months.

One of the last times I saw him, around Labor Day, I went to pick him up in Dunlap to bring him back to Kingston Springs to stay for a while. He said he wanted to start driving again, as if it were possible, and I think he must have known it wasn't, but also that he knew that to get out and get around was his only way of living, and that otherwise he had nothing left. He talked about his old life, basically the time before Elizabeth died, when he still painted and was still on his own, and had her to take care of and to take care of him. Then she went, and he sold his house and moved from place to place, and I kept thinking he was like a living ghost, and he knew it. I wish he could have lived forever, but nobody does.

So is this the best option we have? Live to be old, and watch as everything is subtracted from you, until you are zero. He had nothing left, he had given it all away or lost it or had it taken from him. I think I will always feel like he lost too much that we could have taken, or that we took things too early. He was more than any of us knew how to deal with, and we didn't know how to deal with his slowly fading away. His nurse called my mother early on Tuesday morning to say he was writhing in bed and laughing, and we all took that as a sign, properly, that he was almost finished. He was so tired, I've never seen anyone so tired...

So sad this week, so sad...

frustration '13

so, this past summer, my boss tells me that he's invited to give a retrospective paper on a particular topic as it pertains to a meeting he's been a regular at for almost 20 years. he asks if i'd be interested in writing it with him, and i honestly said no, i don't know the meeting that well, it's not really my core area, i don't have time now to do a retrospective which means all sorts of reading and research that i don't need to do on old things that nobody cares about anymore, and there are other things i'd rather be doing. he seemed to agree and said okay, we won't do it. then, a week later he tells me he agreed to supply the paper, as if i'd agreed, and so i didn't put up a second protest, except probably for a confused look on my face.

so here we are now, the paper is due, i've written it and spent a few good weeks on it, and i'm satisfied with it. i'm not even going to the meeting to present it. so now he wants to continue making changes and modifications to the structure of the thing, and he wants me to make the presentation for him. this is really frustrating. it's too late to fight it, because the paper is there on the schedule, he's going to present it, and i don't *want* to present it, and if i refuse to make the presentation he's not going to be able to do it himself, and it will just cause a fight and a falling out, which is bad because we're currently on good terms.

this is very frustrating. i'm put, again, in this position of paralysis, where there are several other things that i want to do, or need to get done, and instead i have to do this pointless job instead, and so i wind up doing next to nothing. i'm like a ghostwriter. how is this research? i have papers to revise and resubmit, papers to complete and submit, papers to write and complete, experiments to finish and write up, and instead i'm struggling over this stupid retrospective on a topic that i think is basically irrelevant, and in which my *conclusions* are that that work done on this topic over a 20 year period are basically irrelevant. the paper itself begs the question of why the paper has even been written. i think i made a big mistake in letting myself get put into this assignment.

also

a few other observations from china:

in developed, urbanized places, people live, or aspire to live, in flat, spread-out places (single-family houses in subdivisions, or in the countryside); and they go to work in tall buildings in concentrated, densely-built places.

in developing, urbanizing places, people live, or aspire to live, in tall buildings in densely-built places; and they go to work in flat, spread-out places (factories, construction).

all i noticed was that in china, even in small towns, once you get out of the little villages (where each family has a house of their own), the common people live in tall apartment buildings or highrises, but a lot of them are going to work in huge factory floors, although a lot of them are also going to commercial or service-sector stuff in big multistory buildings. meanwhile in the US, common people (except for young people starting out, or the urban poor, or anyone living in a big city downtown) live in houses surrounded by open space, but they tend to go to work in service sector or commercial business in tall, downtown buildings, although many are also going to work on factory floors. so, it's not a perfect 'economic chiasmus', but still an interesting little contrast.

also, this happened several times: after using the second floor bathroom, i would stand by the window to reassemble my multi-layer winter clothing, looking outside through the blinds. across the street, i would see the front window, at ground-level, of another house, with white curtains drawn. just in front of the window was a little tree with what i think were seed pods hanging from the branches, so that i saw the branches against the window curtain background. each time i saw this scene, i at first would think that the curtain had large-print calligraphic characters printed on it, only to shift immediately to seeing the true depthful scene - deja trompé! even after the shift, there would still be a lingering feeling of 'what are the characters, they are too small to read', which would then quickly disappear as it was obviously a wrong question. it did make me wonder whether or not the same sort of scene had stimulated some artful styles of calligraphy..

dinner aura

(this and the previous post were written as dated, but are posted today, 1-5-13; the times are today's time).

last night, just as we were starting our saturday night banquet, i noticed that everything i was looking at seemed distorted, and then realized that a scotoma was developing, just below and right of fixation. i wasn't able to pay much attention to this one, since i had to eat dinner without looking like a lunatic, but it seemed normal; straightish out to the right of fixation, then arcing downward. there was a period early on where the scotoma was very difficult to find, but i think it was just distributed, or at least not exactly the same in both eyes, but was still there. whereas usually the headache would have started about halfway in, this time there was nothing; maybe a slight sense of headache-like pressure behind the forehead, but no pain. i am guessing this was maybe due to the constant alcohol ingestion? by the time the 10-15 minute mark came around, i had probably had at least 2 shots of baijiu.

absence of a headache was good, since following this i went with jp's father, uncle huang, and uncle wang to get my 'feet washed', which really turned out to mean a full-body massage. a full-body massage while fully dressed in winter getup, sweaters and pants and long underwear. it was nice, though! and lucky no headache, since there was a stage of head-beating.

also, i didn't detect any sort of prodrome. in the morning, i had felt it inordinately difficult to form sentences, and made some strange mistakes in chinese, producing strangely wrong words, which i noticed at the time as out of the ordinary. otherwise, nothing obviously in prediction..

random observations:

(rambling chinese vacation edition):

1. due to jet lag, woke up at about 5:30am yesterday, lay in bed for ~1.5hrs. of course a thousand random thoughts ran through my head, but for a while a lay there watching the augenlicht. long, long ago i noticed how it cycles: against the dark, reddish-black background, a brighter cloud coalesces around the fovea, then fades, then coalesces again. the cycle is somewhere between 5-10 seconds, the cloud is a very low-frequency modulation (maybe ~5degrees across) of the high-frequency noise grain.

what i noticed yesterday was that as the cloud fades, some parts of it seem to 'stick'; this is hard to describe. imagine that the cloud was displayed on a screen, and that its brightest parts, around the peak, were 'clipped'; then, as the could fades, the clipped parts persist, then brighten noticeably, then dissipate as the cycle continues. the impression is similar to a very bright afterimage floating in front of a fixated object, except that my eyes were closed, and i was certainly dark adapted. the clipped portions are sharp-edged, small (half or a quarter degree across), with the spatial appearance of little interconnected droplets of a liquid. i wasn't able to tell if they had the same structure on each cycle, but it seemed that they did.

i cannot guess meaningfully what this is. some sort of pattern formation machinery being stimulated by the structure of the cloud cycle, which has a slower decay constant? it seems familiar, so i might have noticed it at some other time in the past when i found myself lying in bed, unable to go to sleep. when i was in college, that happened a lot, because i would have classes in the morning and force myself to bed, despite wanting to stay up until 2 or 3, and so i'd lay in bed for hours sometimes, waiting to sleep.

i also noticed that i could very clearly see the 'eye crank lines', especially when looking down, whereas usually i can't see them when my eyes are closed.

2. when we finally got out of bed yesterday morning, discovered it was snowing. it eventually stopped snowing and started raining, so the weather yesterday was miserable. still, we drove down south to visit family. we went to visit j*'s father's older sister, who i'd never met before, in a village in another corner of fanchang; her home was like something out of a fairy tale, not so surrounded by garbage and chaos like some of the other villages (which are still nice to visit, don't get me wrong). i had jingping take some pictures. there was a mountain running up directly on the side of the village, with a bamboo forest; spread out away from the mountain and the village was a large expanse of vegetable gardens. we had lunch cooked on a wood stove (and with some electricity). i hope that china is able to keep from totally losing this world as it moves on into the future.. all they really need is to find a way to deal with the garbage.

on the way down there, we drove on a new highway which took us through several tunnels beneath the mountains. at some point, to the right, in the distance, maybe a mile or so distant (in the south of wuhu, there are mountains and there are flat plains, and stark, sudden transitionsn between them), through the snowy, rainy, smoggy haze, i saw a massive building, seemingly in the middle of nowhere. it looked like something in DC; the size of the pentagon, ten or twenty stories wide, sixty stories wide. then, a little further south, a gigantic factory or processing plant, like a refinery or the biggest concrete plant you've ever seen. then, a mountain. i didn't bring the GPS to track where we went this time, but i can probably figure it out from memory. this reminds me of last year, something i never wrote down; on the bus back to shanghai, in the distance i could see a glowing tower, probably a hotel, surrounded by nothing else. it was probably fifty stories high, and surrounded by what looked like a 4th or 5th-tier town. maybe we'll see it again this time, since we're probably taking the same bus back.

also on the wuhu note, i've noticed lots of songbirds here in the subdivision, first time in four winters. maybe whatever drove them away is getting better?

3. dinner at uncle's restaurant. dog meat tastes weird. it was worth a try.

4. still on the roman history kick, been reading Tacitus' history of the 'year of four emperors', on the civil war that commenced with the death of Nero. it really is great reading. in the section on Otho's last stand and suicide, i paused for a while and thought about how all this had happened. i still don't know much about roman history, but i've read livy, so i know something about the beginnings of the republic and how it came to be; and i've read plutarch's lives of marius, sulla, crassus, pompey, and caesar, so i kind of understand how the republic cascaded into the empire.

i thought, the romans had all these lawful institutions for separating power, trading offices more-or-less peacefully and agreeably, avoiding autocracy and civil wars. they kept this up for hundreds of years, but only because to have faltered would have probably meant the end of rome, because there were still so many other powerful players in the vicinity. only after those players - the etruscans, the gauls, carthage - were subjugated, only then could the internal struggles really commence. the rise of the emperors, through the disruptions of marius to caesar, put an end to those struggles by ending all the power sharing. but that meant that once an emperor had failed, the struggles would flare again, and there would be civil war. the situation described - and witnessed first-hand - by Tacitus was the first of several times that this would happen, and it would eventually bring the end of the empire.

so i thought all of that, putting together the pieces that so many others have put together so many times, and then i turned the page, and Tacitus himself begins a digression where he outlines the same reflections on the same reasoning, and again i was impressed at the immediacy of reading the thoughts of a person who lived and died more than 1800 years ago.

5. despite the preceding item on how great Tacitus is, i switched yesterday (at the beginning of the next book of Tacitus, on Vespasian's rebellion) to reading Darwin's 'on expressions of man and animals', or whatever the title is. i've wanted to read this for years, never got around to it until there it was, Free on Ibooks. reading Darwin is great because of the way he makes his thinking so transparent; he explains everything iteratively, first in broad terms, then more and more specific, each time tacking on anecdotes or examples with more and more density. origin of species and the descent of man were written similarly, spiraling down from general statements to specific demonstrations, with examples at every level, but there was less anecdote; here, Darwin is on every page noting a story from some friend or acquaintance, or describing the behavior of his own dogs or farm animals. so, the story is solidy anecdotal, but still convincing, because you can see how he is being led at each stage to a question; if such-and-such is true, we should observe this, and here is an example that we all know, or an anecdote that i'm sure you'll recognize (e.g. how a dog acts when in anticipation of something he likes).

i also like all the talk about "nerve-force". the idea that this nerve-force overflows from the channels of immediate use, into channels of frequent or necessarily convenient use, and only later into less frequently used channels, is important in a lot of his examples. also, his 'principle of antithesis' in explaining some expressions is, i think, an interesting example of something more general than an adaptation aftereffect. for example, the excited dog, when it finds that it will not get what it expects, will look dejected - the 'hot-house face' - with this expression explained as, essentially, the aftereffect of adaptation to an excited manner. i think i will look more into this idea of antithesis in behavior..

words

trying, trying, to get to a black belt in tkd. it's hard, because i am not good at tkd. i have no athletic talent whatsoever, but i try anyways. sometimes it goes well.

so i keep hurting my back over the years, and for the most part it's been less frequent in the past 3, what with the regular exercise. however, i hurt it badly, permanently, last year, after *resting* for a month. not resting actually, but working on a grant proposal, doing nothing but sitting/slouching and reading/writing.

so then, lately, i decided to start doing the sunday afternoon core training class, which is basically variations on sit-ups that you do in rounds, over and over again. it's good. i did it this sunday. the day before, i went to the grocery store, and forgot that we were almost out of rice, so i didn't buy any.

monday night we ate the last of the rice, so tuesday night, on the way home, i went by the grocery and bought two bags, because if you buy two you get a discount. then i went home. this was all on foot or by train. with two 15 pound bags of rice. i didn't perceive a problem.

wednesday night i reached out to lift up the toilet seat, and something in my upper back exploded. so no more tkd for the rest of the week, and it hurt a lot. it's mostly better now, hurts, but i'm not partially immobilized anymore. thursday and friday, along with the back pain, my right arm hurt and my hand was numb. so i'm suspicious that the damage wasn't just to a muscle, but to some part of the spinal machinery, although if so maybe it shouldn't be improving so fast.

i wrote a facebook poem about it:

people who stand
on escalators
cervical spinal nerve eight
the north wind
on cambridge street

in other news, i'm like most americans, preoccupied with guns lately. i don't think anybody has a right to have one, that sums up my opinion. oh well.

going to china tomorrow morning! that will be nice, except i have work to do that i'm not interested in doing but have to do anyways. should be alright.

**
also, this came out a few days ago, didn't know where to put it, it's pretty ordinary:

undirected urges
to assemble words
vaguely resembling
the task at hand

sitting quietly
struggling silently
ignoring tomorrow
avoiding time

congealing thoughts
pooling together
into my hands
out of my mouth

watch and wait
the page to complete
vaguely resembling
the task at hand

red boots

m* is visiting the lab, sitting behind me at the desk where p* used to sit. he's leaving friday. i've had several talks with him about methods relating to the blur adaptation studies, and he's really helpful in clarifying certain issues. he's always solidly skeptical.

he has a whole foods paper bag under his desk, i think it's filled with bottles of beer. when you come in the door to the office, if he's sitting there at the desk, you see his back, and the red and brown paper bag sitting on the floor right next to his feet. yesterday, several times, i came in the door and thought immediately i saw him sitting there wearing red cowboy boots, only to realize what i was really seeing. deja trompé!

bo xilai rides my train

Bo Xilai rides my train. He's usually there when I get on at Reservoir on the 9:45. He always has a seat in the rear car, where I ride in the morning. He sits facing the rear, which I figure he does so that fewer people have a chance to recognize him. A lot of Chinese people ride the D train, but I've never noticed anyone seeming to recognize him. Maybe they do and just ignore him.

He wears Nikes and blue jeans. He doesn't look wealthy or powerful. Sometimes I see him reading a Chinese newspaper, but usually he's just sitting there looking around kind of nervously, or napping with his eyes closed. He rides to the Chinatown stop and gets off. His son went to graduate school at Harvard, so he must have some connections to some Chinese people in town.

But still, why is Bo Xilai riding the train in Boston? Isn't he afraid of being recognized, especially in Chinatown? He's supposed to be under house arrest in China, not riding around on public transit in America. He can't assume that everyone will be friendly and understanding. You'd think it would be excellent tabloid material: "Bo Xilai Escapes to Boston". And what's he doing in Chinatown? Maybe he has a job in a store or a restaurant to pass the time, trying to start a new life, or maybe he's going to some kind of a meeting of exiles.

He always looks a little confused and uncomfortable. I feel like everything isn't right with him. Maybe he's homesick? I saw the pictures of his wife in the docket. Does he think she really did what they say she did? I wonder if she's here too, in Boston. I haven't seen her. Maybe he's just lonely. Maybe he doesn't know anyone here, and he goes to Chinatown to remind himself of China.

I wonder what will happen when it's time for Bo Xilai's trial. Will they use a look-alike? Maybe they'll cancel it, or hold it in secret. Maybe they'll announce that he's died. I can't believe that they'll announce that he's escaped. We'll see what happens - it will all be in the news. I won't tell anyone what I know, though, whatever happens. If Bo Xilai wants to stay in Boston and ride the D-Train, it's really none of my business.

train headache

slightly excruciating headache. developed on the train. may or may not be migraine, it's a fuzzy cloud of pain centered between behind my eyes and my palate. maybe a sinus thing instead, or maybe there's an interaction with the winter air and the train heating. nauseated and photophobic. i keep holding my breath.

visual phenomena at the two edges of sleep

1. going to sleep last night, and saw that high t.f. flicker, though i didn't have a headache at the time. actually, haven't had one in almost 2 months, i think. woke up this morning feeling like i had a hangover, but no headache per se, so maybe i had a migraine in my sleep? or, it was an overdose on thai food. there were definitely abdominal repercussions.

2. been meaning to write this down: jingping usually gets up before me what with the school and all, and usually when she gets up to leave it's still dark. if she turns on the bedroom light and i'm sufficiently conscious but still with eyes closed (and maybe also if my face is pointing in the right direction), i will see a quick red flash. nothing interesting, right? but the flash has a geometric structure, a hexagonal lattice, like an M-scaled honeycomb. a typical sort of visual field hallucination, but i only started noticing it in recent months.

that is all.

blur or no blur?

Some notes on the aftereffects of a paper revision I just submitted (not coincidentally linked to the rambling at the end of the previous entry):

The big problem I have left over after the last revision of the blur adapt paper is this: does it mean anything? I've wound up half convinced that while I have a good explanation for a complex and strange phenomenon, it may be seen as boiling down just to a measurement, by visual system proxy, of the stimuli themselves. That is, all the stuff about selectivity, slope changing, symmetry of adaptation, etc., might all just be a figment of the wholly unnatural way of blurring/sharpening images that we've used.

What's left? The method is good. There are also questions about the spatial selectivity of the phenomenon, and, most importantly I think, about its timecourse. If blur adaptation is something real and not just a spandrel interaction between contrast adaptation and strange stimuli, it doesn't make a lot of sense that it would manifest in everyone in the same way unless it did have some sort of perceptual utility. The utility that exists is a good question. Let's make a list:

1. Changes in fixation across depths. Most of the people who do these experiments are young and have good accommodation. Blur is one of the things that helps to drive accommodation, to the point where if everything is working correctly, within a few hundred (less?) milliseconds of changing fixation in depth, the image should be focused. So, blur adaptation would not be useful in this situation. Maybe it's useful when you're older, and for this reason it sits there, functional and in wait, for the lens to freeze up? Seems unlikely and implausible, but possible. When you get old, and look at different depths, the sharpness of the image will change, and it would be nice to have some dynamic means of clawing back whatever high s.f. contrasts might still be recoverable in a blurred image.

2. This begs the question of how much can be recovered from an image blurred locally. That is, the slope-change method is basically using an image-sized psf, which is what makes it so weird. Blur doesn't usually occur this way, instead it occurs by a spatially local psf applied to the image, like a gaussian filter. If an image is gaussian blurred, how much can it be sharpened?

3. Viewing through diffusive media, like gooey corneas or fog or rain, or muddy water. The latter phenomena, if I'm not mistaken, affect contrast at all frequencies, while stuff-in-the-eyes effects optical blur, i.e. more attenuation at high than at low frequencies. It would be nice to know, in detail, what types of blur or contrast reduction (it might be nice to reserve 'blur' for the familiar sense of high s.f. reduction) occur ecologically. We also have dark adaptation, where the image is sampled at a lower rate but is also noisier. The noise is effectively a physical part of the retinal image (photon, photochemical, neural), meaning that it's local like an optical defect and not diffusive like fog. Maybe blur adaptation is mostly good for night vision?

4. Television. CRTs. Maybe we're all adapted, long-term and dynamically, to blurred media. All captured and reproduced media are blurred. CRTs were worse than current technology, resulting in displayed images that were considerably blurrier than the transmitted images, which themselves were blurred on collection and analog transmission. Digital images are blurred on collection, although light field cameras seem to be getting around this, and digital displays are physically much less blurred. Maybe those of us who grew up watching CRT images, and accepting them as a special sort of normal, adapt more than the young people who are growing up with high-resolution LCD images?

5. Texture adaptation, i.e. adaptation to the local slope of the amplitude spectrum, i.e. exactly what is being manipulated in the experiments. This would be fine. Testing it would be a bit different; subjects would need to identify the grain or scale of a texture, something like that. I think that the materials perception people have done things like this. Anyways, this sort of adaptation makes sense. You might look at an object at a distance and barely be able to tell that its surface has a fine-grain texture, so a bit of local adaptation would allow you, after a few seconds, to see those small details. On the other hand, if you get in really close to the object so that the texture is loud and clear, and you can even see the texture of the elements of the larger texture, especially if there's a lot of light and the texture elements are opaque, this is effectively a much sharper texture than what you were seeing before, even within the same visual angle. The 1/f property of natural images is an average characteristic. Locally, images are lumpy in that objects represent discontinuities; textures on surfaces usually have a dominant scale, e.g. print on a page has a scale measured in points, and that will show up as a peak in the amplitude spectrum. So, texture adaptation, where the system wants to represent detail, seems like a plausible function for what we're calling blur adaptation. Maybe the system should work better somehow if images are classed in this way?

6. Parafoveal or 'off-attention' defocus. We almost always fixate things that are sharp, but if the fixated object is small, whatever is behind it will be blurred optically. Similar situation if the fixated object is viewed through an aperture, the aperture will be blurred. Whatever adaptation occurs in this situation must be passive, just contrast adaptation, as I can't imagine that there's much utility to the small gain in detail with adaptation to a gaussian blur.

For all of these situations, spatial selectivity makes sense but is not necessary. Even if you're viewing a scene through fog, nearby objects will be less fogged than faraway objects, but it all depends on where you're fixating; other object at different depths will be more or less fogged. At any rate, foveal or parafoveal adaptation is most important, as peripherally viewed details are, as far as I can understand, subordinate. If the process is spatially localized, as it should be if it is what it seems to be, then global adaptation is just a subset of all possible adaptation configurations. Temporal selectivity is more questionable. If the process is genuine, and not just broadband contrast adaptation (though this begs the question of what should the timecourse be for contrast adaptation), how fast should we expect it to be? If it's mostly used for long-term (minutes) activities (fixating muddy water, looking for fish; other veiling glare situations; gooey eyeball; accommodation failure), maybe it could stand to be slower, with a time constant measured in seconds, or tens of seconds. If it's mostly used for moment-to-moment changes in fixated structure, i.e. texture adaptation or depth (off-attention), it should be fast, with a time constant measured in hundreds of milliseconds.

Actually measuring the temporal properties of the adaptation might therefore help to some degree in understanding what the process is used for.

reading about history

An idle essay on history, for the holiday!

In the past couple of years, a good portion of my recreational reading has been history, and some of that has been by ancient historians: Plutarch, Sima Qian, Livy. For the past few weeks, I've been alternating between two books, a collection of abridged Livy (from the Ad Urbe Condita) and Wittgenstein's Tractatus Logico-Philosophicus, which is a study of how language is connected, or can potentially be connected, to reality. I'm not claiming to fully understand the Wittgenstein, but there has been an interaction.

There are lots of reasons why reading history is enjoyable. The main reason, for me, is that it is so edifying: you are learning how the world came to be the way that it is, and you're also learning about certain constancies of the human condition, mistakes and actions and etc that have been repeated over and over again for thousands of years. Another reason is that it is entertaining in the same way that reading fiction is entertaining: there are heroes and villains, victories and tragedies, and all of it is ambiguous and complex, at least in hindsight.

What the TLP made me think about was this (although not in the confusing terms of propositions, pictures, facts, etc): the page one reads is a surface into which has been pressed different shapes. When one reads, one is feeling these shapes, and mentally reconstructing whatever it was that impressed them. When one reads fiction, the impressor is, supposedly, always secondhand, in that it is the mind of the author that has been impressed, and the author has reconstructed ideas based on those impression, recombined them into mental realities, and then created new impressions based on those mental realities in the page. One then uses those impressions to reconstruct the author's mental realities. Since these reconstructions are not based on physical reality, they constitute in the language of the TLP false facts (although, strictly, many of the components of these false facts must be true; a falsehood cannot be sensible if it is not seemingly possible, its possibility being dictated by the local truth of its parts).

When one reads history, then the intention is that physical reality is impressed into the page, and that when one reads history and reconstructs his own mental realities, these should be (or be close to being) true facts. This is the intention of the honest historian, but he must inevitably fail, because he cannot base all, or even most, of his impressions on physical realities. Historians gain their knowledge by reading what was written by others before them, and then they compile what they have read into narratives that can be understood holistically by others. The historian must judge what are true and false facts, and impress only the true facts. Since other writers may not have thought of themselves as historians, and may not have been intent on impressing true facts, these judgments will be difficult, and the historian will sometimes fail.

So, when reading history as a naive consumer of text like myself, one is in the interesting situation of feeling out these impressions and forming mental reconstructions of the impressors, which are actually impressions of reconstructions of impressors that are actually reconstructions themselves and et cetera. Some of the impressions are mostly true (with local falsehoods), and some must be mostly false (with local truths). It's like Indiana Jones and the Holy Grail, except there's no reward or punishment for deciding that one or another fact is true or false. In reading fiction, the decision is implicit in the definition, but in reading history, you get the sense of walking along the true side of a very fuzzy edge, a transition into the false side. This transition gets broader and broader the further back in time one goes.

This then gets back to another issue which I'd like to write about sometime: the ubiquity of blur. All systems for transmitting information lose local details before they lose fundamentals. High spatial frequencies are lost in image formation; high temporal frequencies are lost as sound travels through a medium; sharp edges on an object are worn down by friction over time; genetic mutations effect molecular changes in the phenotype; and the details of history - names, dates, the precise unfolding of events - are misremembered or, mostly, forgotten. These are details in the literary sense, but they seem exactly analogous to physical details: what happened in Caesar's final days? Did he go to the forum in spite of warnings? Was Brutus really his son? These sorts of details, the answers to these sorts of questions, are permanently forgotten, but we know the larger, deeper, important events: Caesar was murdered by a conspiracy of Senators.

Interestingly, in the same way that a knife might be sharpened, or faded images might be retouched, old stories about the past might be sharpened up with added details; doped with false facts, to bring them into narrative focus. Caesar was warned about the Ides of March; he saw Brutus and said, "You too, my son?" The doping could also be with irrelevant facts: this is what you could buy from a street vendor in those days, this is what the men and women of this station wore on their feet. This sharpening, false or irrelevant, is enjoyable in a special way when it comes from someone who was writing more than 2000 years ago, because it is more immediate: nothing (except for the translator) has touched these impressions since they were formed. It's like holding something very, very old in your hands.

finally a post about those eye crank lines

has anyone ever tested basic visual psychophysics as a function of gaze direction? i don't think so. would it be interesting or important to do so? i think so.

1. when i crank my eyes out as far as i can, i see weird phosphene patterns around my foveae (below). nobody has given me a good explanation for what these phosphenes are, except that they are probably produced by some sort of tension or torsion on the optic nerve. this isn't much of an explanation, because the phosphenes are so local and fine that if it was torsion i would expect them to be everywhere. it could be the correct explanation, but then i need an explanation for why they aren't everywhere, or what is special about foveal optic nerve fibers etc etc in their placement in the optic nerve. the sort of thing i guess i could figure out from reading.

whatever the cause of this effect, it means that in the extreme, direction of gaze has an effect on low-level perception, i.e. i am seeing spatial phosphenes - which, really, look like band-pass patterns - and not hallucinating faces or whatever. so, it stands to reason that less extreme directions might also have effects that are more subtle.

anyways, i hope i am not tearing apart my optic nerves by doing this experiment. i try not to do it too often, but it's like thinking about reciting pi. when you think about reciting pi, you have to recite as many digits as you can remember. you can't stop. give me a second.

2. if e.g. contrast sensitivity is entirely determined by retinotopically coordinated visual mechanisms - i.e. retina, LGN, V1, striate cortex - direction of gaze shouldn't make any difference, because these areas don't know anything about direction of gaze. but visual areas in the parietal cortex do know about direction of gaze - areas like LIP and VIP combine input from the visual system, of such quality that it is used to plan eye movements, with proprioceptive, vestibular, motor, and other inputs.

it's implicit in the theory of psychophysics - the theory that physical stimuli are translatable into perceptual states, which are then behaviorally accessible - that the last stage of vision is motor, since no psychophysics can be done without motor responses. this is one reason why neuroimaging is not psychophysics.

so, if vision interacts with non-visual inputs, and if these same inputs mediate behavioral measurement of visual ability - i.e. psychophysics - then is it reasonable to suppose that direction of gaze should affect basic visual abilities? a good hypothetical mechanism for producing an effect would be the internal noise source. no one should suppose that the noise limiting performance is entirely visual, because this assumes that the rest of the system is deterministic, which it is not. since the rest of the system is not deterministic, the portion of the random variation that is contributed by the parietal cortex might well vary with the tonic motor state of the system; the part of the brain that is guiding or maintaining the motor aspects of the system, and mediating the responses of the system according to the experiment design, might be better adapted or learned in one gaze state than in others.

3. visual neglect. i guess this is a higher-level thing, but from what i've heard, it's independent of basic sensitivity; how could this have been confirmed? how can basic testing be carried out with the same quality in the neglect region as in the unaffected region? this sounds like something that's been tried over and over, and that i could go read about. a quick survey of some titles, abstracts, and a couple of the most relevant-sounding papers suggests that when such sensitivity has been measured, its in the non-neglect areas, but that the researchers are nonetheless looking for a connection. there's a paper where they suggest there's no difference in contrast sensitivity or s.f. discrimination between two groups of stroke patients, some with neglect symptoms, some without; that could mean that even a stroke big enough to cause neglect, while sparing early visual cortex, won't bother basic sensitivity, or that any serious enough stroke will impair sensitivity on basic tasks. hm...

stack puzzle

Okay, I’ve been wondering for a while whether or not something is a valid question – a good question or a bad question. It is related to a few entries I’ve written here in the past year (esp. this and this), and to a paper that I’m about to get ready for submission.

The question: are the percepts contributed by different layers or modules of visual processing perceived as embedded within one another, or as layered in front of or behind one another?

Such percepts could include brightness, location and sharpness of an edge, its color, its boundary association; color and shape and texture of a face, its identity, its emotional valence, its association with concurrent speech sounds; scale of a texture, its orientation, its angle relative to the frontal plane, its stereoscopic properties.

All of these, and more, are separately computed properties of images as they are perceived, separate in that they are computed by different bits of neural machinery at different parts of the visual system hierarchy. Yet, they are all seen together, simultaneously, and the presence of one implies another. That is, to see an edge implies that it must have some contrast, some color, some orientation, some blur; but this implication is not trivial. That is, a mechanism that senses an edge does not need to signal contrast or color or orientation or scale; the decoder could simply interpret the responses of the mechanism as saying ‘there is an edge here’. To decode the orientation of an edge requires that many such mechanisms exist, each preferring different orientations, and that some subsequent mechanism exists which can discriminate the responses of one from another, i.e. the fact that the two properties are both discriminable (edge or no; orientation) means that there must be a hierarchy, or that there must be different mechanisms.

So, whenever something is seen, the seeing of the thing is the encoding of the thing by many, many different mechanisms, each of which has a special place in the visual system, a devoted job – discriminate orientation, discriminate luminance gradients, discriminate direction of motion, or color, etc.

So, although we know empirically and logically that there must be different mechanisms encoding these different properties, there is no direct perceptual evidence for such differences: the experience is simultaneous and whole. In other words, the different properties are bound together; this is the famous binding problem, and it is the fundamental problem of the study of perception, and of all study of subjective psychology or conscious experience.

This brings us to the question, reworded: how is the simultaneity arranged? From here, it is necessary to adopt a frame of reference to continue discussion, so I will adopt a spatial frame of reference, which I am sure is a severe error, and which is at the root of my attempts so far to understand this problem; it will be necessary to rework what comes below from different points of view, using different framing metaphors.

Say that the arrangement of the simultaneous elements of visual experience is analogous to a spatial arrangement. This is natural if we think of the visual system as a branching series of layers. As far as subjective experience goes, are ‘higher’ layers in front of or behind the ‘lower’ layers? Are they above or below? Do they interlock like... it is hard to think of a metaphor here. When do layers, as such, interlock so that they form a single variegated layer? D* suggested color printing as something similar, though this doesn’t quite satisfy me. I imagine a jigsaw puzzle where the solution is a solid block, and where every layer has the same extent as the solution but is mostly empty space. D* also mentioned layers of transparencies where on each layer a portion of the final image – which perhaps occludes lower parts – is printed; like the pages in the encyclopedia entry on the human body, where the skin, muscles, organs, bones, were printed on separate sheets.

But after some thought, I don't think these can work. An image as a metaphor for the perceptual image? A useful metaphor would have some explanatory degrees of freedom; one set of things that can be understood in one way, used to understand something different in a similar way. Where do we get by trying to understand one type of image as another type of image? Not very far, I think. The visual field is a sort of tensor: at every point in the field, multiple things are true at the same time, they are combined according to deterministic rules, and a unitary percept results. Trying to understand this problem in terms of a simpler type of image seems doomed to fail.

So, whether or not there is a convenient metaphor, I think that the idea of the question should be clear: how are the different components of the percept simultaneously present? A prominent part of psychophysics studies how different components interact: color and luminance contrast, or motion and orientation, but my understanding is that for the most part different components are independently encoded; i.e. nothing really affects the perceived orientation of an edge, except perhaps the orientations of other proximal (in space or time) edges.

Masking, i.e. making one thing harder to see by laying another thing in proximity to it, is also usually within-layer, i.e. motion-to-motion, or contrast-to-contrast. Here, I am revealing that my thinking is still stuck in the lowest levels: color, motion, contrast, orientation, are all encoded together, in overlapping ensembles. So, it may well be that a single mechanism can encode a feature with multiple perceptual elements.

Anyways, the reason why I wonder about these things is, lately, because of this study where I had subjects judge the contrast of photographic images and related these judgments to the contrasts of individual scales within the images. This is related to the bigger question because there is no obvious reason why the percept contrast of a complex, broadband image should correspond to the same percept contrast of a simple spatial pattern like a narrowband wavelet of one type or another. This is where we converge with what I have written a few months ago: the idea of doing psychophysics with simple stimuli is that a subject’s judgments can be correlated with the physical properties of the stimuli, which can be completely described because they are simple. When the stimuli are complex and natural, there is a hierarchy of physical properties for which the visual system is specifically designed, with its own hierarchy, to analyze. Simple stimuli target components of this system; complex stimuli activate the entire thing.

It is possible that when I ask you to identify the contrast – the luminance amplitude – of a Gabor patch, you are able to do so by looking, from your behavioral perch, at the response amplitude of a small number of neural mechanisms which are themselves stimulated directly by luminance gradients, which are exactly what I am controlling by controlling the contrast of the Gabor. It is not only possible, but this is the standard assumption in most contrast psychophysics (though I am suspicious that the Perceptual Template people have fuzzier ideas than this, I am not yet clear on their thinking – is the noisiness of a response also part of apparent magnitude?).

It is also possible that when I ask you to identify the contrast of a complex image, like a typical sort of image you look at every day (outside of spatial vision experiments), you are able to respond by doing the same thing: you pool together the responses of lots of neural mechanisms whose responses are determined by the amplitude of luminance gradients of matched shape. This is the assumption I set out to test in my experiment, that contrast is more or less the same, perceptually, whatever the stimulus is.

But, this does not need to be so. This assumption means that in judging the contrast of the complex image, you are able to ignore the responses of all the other mechanisms that are being stimulated by the image: mechanisms that respond to edges, texture gradients, trees, buildings, depth, occlusions, etc. Why should you be able to do this? Do these other responses not get in the way of ‘seeing’ those more basic responses? We know that responses later in the visual hierarchy are not so sensitive to the strength of a stimulus, rather they are sensitive to the spatial configuration of the stimulus; if you vary how much the configuration fits, you will vary the response of the neuron, but if you vary its contrast you will, across some threshold, turn the neuron on and off.

I don’t have a solution; the question is not answered by my experiment. I don’t doubt that you can see the luminance contrast of the elements in a complex scene, but I am not convinced that what you think is the contrast is entirely the contrast. In fact, we know for certain that it is not, because we have a plethora of lightness/brightness illusions.

No progress here, and I'm still not sure of the quality of the question. But, maybe this way of thinking can make for an interesting pitch at the outset of the introduction of the paper.

meh

I keep noticing, lately, near- and far-peripheral flashes, phosphenes. There was one a few minutes ago, maybe 10deg below fovea, very obvious and yet hard to localize (it was almost as though it extended close to the fovea); I checked for a blindspot, found none. So, based on all these recent sparky things, I predict something happening in the next few days (especially since the BA paper is just about done, so I'm about to go through another relax-contract phase).

probability/likelihood

probability of an event occurring
likelihood of a condition existing

how often have i misused these words? unknown.

if i search this blog, i find one clear misuse of 'likelihood', in "a specific instantiation..." ("likelihood of a pass"); i use the term two other times, in the first post ever and in a later one that refers to that one. in those instances (likelihood that you are alive at age x) i think it's ambiguous, but i'll count those as accurate.

amazingly, there is only one post where i use the word 'probability' in the relevant context. and i can't tell if i'm using it right or not. i'm kind of disappointed in myself.

seems i've fallen off the HAZ-PJ wagon. writing is going well, though, which is good.