Saturday, July 28, 2012

Ripples in the memory of space

Progress in figuring out how the hippocampus replays navigation memories.

While it would certainly be nice for our minds to be, as they intuitively present to us, disembodied and perfect, they turn out to be more like machines, whose workings are amazingly intricate, but quite physical. A good deal has been learned about a few aspects of memory- how it gets recorded in synapses and in anatomical locations in the brain like the hippocampus, and how it is read back out.

The recent paper describes how spatial memory in rats relates to specific electrical/nerve signals called sharp wave ripples, or SWR for short. It was previously found that during sleep, rats (and by analogy, and more obviously, humans and dogs) replay scenes from the awake state in rapid fashion, so that researchers with sufficient electrodes in the subject's brain can even trace where the rat is in a dream, relative to a training maze it has been sent through during the day.

SWR's are common during these sleep+dreaming episodes, and are known to correlate with better learning. But SWR's take place in the awake state as well, and the current paper finds that they correlate with spatial memorization, and thus learning & performance in tests like mazes.


The experimental approach was to find anatomical locations where SWR were taking place in the hippocampus of rats while they were being trained to a new maze task, and then interfere electrically with those signals in a precise way that detects the beginning of a ripple and within 25 milliseconds cancels the rest of it, (total of about 50-100 milliseconds, typically). As a control, blasts were sent to the same locations, but at different times that didn't interfere with the SWR signal.

Experimental protocol. Animals while awake and active, were electrically recorded and also zapped with SWR-disrupting signals (red line) that cancelled the SWR replay sequence within 25 milliseconds. The green line marks when the SWR was automatically detected. Bottom right is a blow-up of the upper right electrical trace of one disrupted nascent SWR. The bar is 50 ms and 200 microvolts.

Rats with hippocampus damage eventually learn to go down the correct arms of the maze, but take far longer than normal rats. The job involves two quite different tasks- remembering which of two forks to take (the outbound decision). The rule is imposed by the experimenter, in an alternating sequence, using visually distinct mazes in successive trials, which requires remembering where one is and also what the prior trip was like. Second is the ability to remember how to get back to the start of the maze, (the center arm), which requires some degree of memory of where one is and where that was, which is, in a place-cell coordinate system, always the same. The experimenters claim that the inbound task is substantially easier, and it is the outbound test where they have in previous work established that rats use memory replays of past trips, (perhaps using more remote memories), not the inbound task.

The result was that only the outbound task was impaired by shorting the SWR signals. The inbound task was still learned at the normal speed. Whether the memory process is conscious or unconscious, the researchers were able to specifically interfere with the rat's thought process through a fine-grained electrical counter-stimulation; a fascinating development.

What are SWR's? They have been characterized over the last decade as rapid replays of navigation markers, (such as place cell firing), speeded up in time and replayed either forwards or backwards. They represent firing of place cells from throughout the hippocampus, as they would during a travelling sequence going from location to location, only the rat is at rest, and the sequence is speeded up twenty-fold! They are thus believed to constitute memory and simultaneously a way to convey this memory to other areas of the brain. It is truly a remarkable story.

Here are a few quotes from researchers doing this work:
"Sequences of neural activity occurring at the third time scale are observed during both sleep and awake but restful states, when animals are paused and generally inattentive, and are associated with sharp wave ripple complexes (SWRs) observed in the hippocampal local field potentials. During the awake state, these sequences have been shown to begin near the animal’s location and extend forward (forward replay) or backward (backward replay), and have been hypothesized to play a role in memory consolidation, path planning, and reinforcement learning." - thesis by Anoopum Gupta, 2011.

"During pauses in exploration, ensembles of place cells in the rat hippocampus re-express firing sequences corresponding to recent spatial experience. Such 'replay' co-occurs with ripple events: short-lasting (approximately 50-120 ms), high-frequency (approximately 200 Hz) oscillations that are associated with increased hippocampal-cortical communication. In previous studies, rats exploring small environments showed replay anchored to the rat's current location and compressed in time into a single ripple event. Here, we show, using a neural decoding approach, that firing sequences corresponding to long runs through a large environment are replayed with high fidelity and that such replay can begin at remote locations on the track. Extended replay proceeds at a characteristic virtual speed of approximately 8 m[eters]/s[econd] and remains coherent across trains of ripple events. These results suggest that extended replay is composed of chains of shorter subsequences, which may reflect a strategy for the storage and flexible expression of memories of prolonged experience." - abstract by Davidson, et al. 2009

"As we have noted, SWR-associated replay has been found to evolve approximately 20 times faster than behavior, and SWRs are on the order of 100 ms in duration. Given a running speed of 0.5 m/s, this means that the replay seen during a single SWR should recapitulate approximately 1 m of behavior." 
"We make several novel contributions: we show that replay proceeds at a relatively constant 'virtual' velocity; that it can proceed over trajectories as long as the complete environment; that this extended replay spans trains of closely-spaced SWRs; and that replay can begin at locations remote from the animal." - thesis by Thomas Davidson, 2009
Included in these findings is that SWRs can encompass not only replays of where rats have been, up to large areas and forward and reverse sequences, but also paths they have never taken, but could take, suggesting that planning may be taking place. So basically, (and however crudely and invasively), scientists are gaining the technology and knowledge to begin to eavesdrop on what rats are thinking- what they are remembering and what they are planning.


  • How much must we destroy for oil?
  • Atheism - out & proud.
  • Salon's very funny New Yorker video drama.. especially the "shrink" episode.
  • Religion, bad philosophy, and immorality seem to go together alot.
  • Republican unworthiness continued.. fiscal edition. "There’s a reason why we can’t seem to make any progress on our fiscal mess: One of our two political parties has gone nuts."
  • Cringely on IT outsourcing.. India's high school graduates man IBM's services, more or less.
  • Europe.. is it nothing but class warfare, like it is in the US? "Unfortunately for the German population, while German business profited handsomely, and  German Banks exported capital to the rest of the world, the costs were borne by German  workers who faced wage pressure."  (Capital which is, incidentally, going down the tubes. But no matter!)
  • Open corruption continues in the US.
  • MMT crows about its calls on the euro.
  • But Margaret Thatcher, bless her, saw the euro crisis coming too.
  • Bill Mitchell explains what he thinks is wrong with Alan Blinder's suggestion to stop interest support payments on bank reserves.
  • Economics quote of the week, from Bill Mitchell, from an NGO report. Wealth doesn't trickle down, it washes out to sea.
"A global super-rich elite has exploited gaps in cross-border tax rules to hide an extraordinary £13 trillion ($21tn) of wealth offshore – as much as the American and Japanese GDPs put together … at least £13tn – perhaps up to £20tn – has leaked out of scores of countries into secretive jurisdictions such as Switzerland and the Cayman Islands with the help of private banks, which vie to attract the assets of so-called high net-worth individuals."



Saturday, July 21, 2012

I attend a religious service

Interesting rituals pervade the ritualized combat ... of baseball.

Take me out to the ball game,

Oh, take me out to the ball game! America's pastime is not only one of the most refined and elegant sports, but the home of endless rituals and symbolism. It could be viewed as the center of our civic religion, with politics a peripheral and grubby afterthought. And it is better than typical religions- a living ritual enacting the competitive spirit that truly characterizes American existence, enclosed within a lovingly maintained structure of rules, decorum, and tradition. Thankfully, my town recently acquired a ultra-minor professional baseball team, which is a joy to watch.

Ball games have a long history in the Americas as sacred events. Bats were even used in some prehistoric cases. In our modern game, the leading actor (i.e. the pitcher) stands on a central mound, reminiscent, if only in a small way, of the religious mounds of pre-Columbian America. This lonely figure faces the most trying test, from which he (or she!) will emerge either a hero, or defeated by Lilliputians sent up to hit against him. Surrounding him is a perfect square, the number four being highly significant in many cultures and mythologies, not to mention in nature generally. The opposing players seek to circumambulate the square, a common religious action, and while typically mark of respect, in this case it is an act of power over rival priests. It is a passion play of sorts, though the outcome is open rather than closed.

Take me out with the crowd;

We begin with communal singing- the national anthem, hands over hearts. Then it is on to chanting, clapping, stomping, waving, dancing, all in a re-ligio... sense of communal connectedness. An invisible being announces the service, keeping everyone onboard with a narration of key events and rituals. In between the enactment of the heroic contest in the main drama, spectators and miscellaneous notables come on to the field to take cameo turns, throwing out the ceremonial first pitch, running races and other contests, winning boons, honoring aged or fallen heros. Altar boys, er bat boys, run out one of the priestly tools- the pitcher's rosin bag, and serve the heros unstintingly through the game. The seventh inning stretch brings on the classic baseball song in chorus.

Buy me some peanuts and Cracker Jack,

Then it is on to communal eating of characteristic tribal foods. The heart of Americana- hot dogs, corn dogs, peanuts, chili, ice cream. I guess nachos count as well- the mingling of native corn with the newcomer's dairy. Healthy? No. Spiritually nourishing? You bet. While no one makes claims of transubstantiation for these foods, they make and evoke memories of unusual strength.

I don't care if I never get back.

The admission gate marks a sacred threshold, entrance to the outer precincts of the progressively more sacred central field, square, and mound. Time is suspended, as baseball does not run on a clock, but finishes whenever the ritual drama has run its course by its own arcane rules. Nor does the accumulating score lead relentlessly to the final fate. It ain't over till it's over, to use the classic maxim, as pitching breakdowns can lead to dramatic changes late in the game.

Let me root, root, root for the home team,

While in many sports, each team has its partisan section cheering it on, (soccer hooliganism comes to mind), in baseball it is more customary for all the spectators to root for the home team only, at least in the sort of minor league game portrayed here. While this may be impolite to the visiting team, it creates a civically unified atmosphere.

The Greeks made athletic festivals central to their culture, as have many others. It was a form of divination, showing whom the gods favored, and whom not. Sport was one way to express and strengthen the civic cult, as well as to transcend it, in the setting of pan-Hellenic games, even though they didn't quite get around to replacing war with sport.

If they don't win, it's a shame.

These days, the rules- i.e. moral concepts of fairness and popular legitimacy- matter far more than theories of divine favor. As a civic religion, it imbues a fundamentally secular activity with many of the narratives and spiritual archetypes embedded in human nature.

The rules of baseball are just a little more sacred and tradition-bound than those of other sports. Thus the steroid scandal hit baseball particularly shamefully, though far, far more damaging derelictions happened elsewhere in the culture, as our leaders (one of whom had helped run a baseball team, oddly enough) started a gratuitous war, showered money on the well-to-do, and raped the poor, greedy, & unsophisticated with predatory loans, making way for the current economic crisis. Baseball itself became ever more besotted with corporate advertising, corporate stadiums, and a fixation on money generally. Rituals like baseball are inescapably connected with the trends afoot elsewhere in the culture. Demons can not be exorcised by ritual alone, but only by taking the lessons of the ritual- fairness, integrity, diligence, persistence, respect- into our wider lives.

For it's one, two, three strikes, you're out,

The high priest and the low priest are having a stylized game of catch, with the all-white sacred ball. (I'm not going to get into Freudian theories about the bats, balls, gloves, etc.!). Does the batting team of priests from the competing civitas have the power to interrupt this golden line? If not, the pitcher has achieved a perfect game. If the batters do get hits, can the fielding team prevent the ball from touching the mundane earth? If not, can the fielders at least prevent the ball from escaping the sacred precincts, inner and outer?

Which team has greater occult powers, exhibited through their skill and luck? The trip around the square marks the stations of this passion play, with home the ultimate goal, just as it was for Dorothy. An umpire, of yet another priestly class, maintains the balls, discarding those sullied by contact with the earth. He also lovingly sweeps home plate back to its pristine condition and validates the golden line drawn between pitcher and catcher.

At the old ball game.

Who gets to play the hero? This is far more than a question of skill. The players represent their civic tribes, and represent the archetypal hero with occult powers. This is why breaking the color line in baseball was far more significant than it was in other sports, as baseball was and remains more civically identified and more archetypally powerful than sports like basketball and football.

One reason is that baseball has very little physical contact. The ball is the central mediator- between players and between teams. Even tag-outs are made through the glove, with the ball couched within, or at its most direct, with the ball directly held in the hand outstretched. Even in the extremis of the bean ball, the ball still mediates, showing its dark power. However, the bean ball is a serious breach of decorum, both violating the golden line and bespeaking a loss of control/power by the pitching team- a descent from civilized rules (i.e. sacred ritual) into barbarity.

It is hard to leave- to break the spell of the sacred service, space, actors, and drama. But it wouldn't be sacred if there weren't mundane life to provide a backdrop.

  • Another author investigates the diamond way.
  • Basketball is an OK game too: American ballet, to baseball's mystical drama.
  • Character in the financial elites, or lack thereof. Do they really have to be psychopathic?
  • "Worst states for business" are the best states for people.
  • Is corruption becoming unstoppable? Does money have to ruin all public functions?
  • Tom Coburn- standing up to the terrorists, a little.
  • Law of the sea.. further unworthiness of the Republican party.
  • This is the soul, which we can not remove.
  • Krugman on global scorching/burning/warming ...
  • Economics quote of the week, by Bill Mitchell, speaking of stagnation in the US, as well as the nature of intergenerational responsibilities.. are they real or are they financial?:
"The pro-cyclical government cutbacks have introduced a vicious circle of income loss, saving loss, wealth destruction, continuing real estate crisis, loss of state and local revenue, further cutbacks according to the application of their inappropriate fiscal rules (balanced budget amendments). 
The pro-cyclical nature of state and local government employment is one of the principle reasons the US recession has endured and will ensure the long-term damage to that nation’s vitality and ability to provide high quality services to its people. 
The reasoning in the public debate about the future consequences of government budget deficits is wrong-headed. The capacity of the US to provide for an ageing society amidst the long-term decline in its industry doesn’t depend on cutting in to public spending now – which is patently causing law and order to deteriorate, the standard of public education and health to slip. 
Exactly the opposite response is required. Schools need to be revitalised. Communities need to be sure the streets are safe so that businesses will have an incentive to invest. People need to be mentally and physically well."
  • Economics bonus graph of the week: Krugman on middle class stagnation:

Sunday, July 15, 2012

Take the money and sit around

Who's lazy in neoclassical economics?

I ran across what appears to be a semi-famous study that has been understood (on the economic right) to defeat Keynesianism. A paper by Cohen, Covan, and Malloy (CCM) from 2009 claims that when states get free money from the federal government, their GDP goes down. This is perhaps a mini-resource curse, like the oil curse that leads to bad governance, corruption, and bad political as well as economic outcomes. As a non-expert, I can not entirely judge their work. (Other critiques, incuding a typically sultry one by David Brooks who implies that no economic theory fared well in this recession, which is not true.)

Their analysis is based on the natural experiment of changing political fortunes. When, in the US, the legislature changes hands, the new party in the majority takes over all the chairmanships that write budget bills, and in typically corrupt fashion, channels vast amounts of money to the chairman's states and districts. The same thing happens at a smaller scale when a legislator gains a committee chairmanship through natural attrition. CCM claim that these switches are essentially unlinked to other economic phenomena and form a natural experiment on the effects of exogenous money on otherwise stable economies.
"During the year that follows the appointment, the state experiences an increase of 40-50 percent in their share of federal earmark spending, a 9-10 percent increase in total state-level government transfers, and a 24 percent increase in total government contracts."
They put the Keynesian prediction as being that GDP would go up in these states, (through direct added money), and the neoclassical prediction that GDP would go down, due to impairment of investment incentives and general human laziness. They find that GDP goes down. Win for neoclassical economics?!
"In the year that follows a congressman’s ascendency, the average firm in his state cuts back capital expenditures by roughly 15%. These firms also significantly reduce R&D expenditures and increase payouts to their investors. The magnitude of this private sector response is nontrivial: in the median state (which receives roughly $452 million per year in increased earmarks, federal transfers, and government contracts as a result of a seniority shock), capex and R&D reductions total $48 million and $44 million per year, respectively, while payout increases total $27 million per year."
Note that these are not very large effects, compared with the government injections. Only a fraction of the new largesse is socked away as savings, share buy-backs, etc. Where does the rest go, if overall GDP is claimed to go down? CCM never say, and I speculate that this is an enormous hole in the analysis. Their metric of employment is also "firm-level" employment, (indeed restricted to publicly traded companies), ignoring the public sector and small business employment that would probably be the main result of increased federal money.
"Also, consistent with Keynes’ view that crowding out should only occur under conditions of full employment, we find a stronger firm response to spending shocks when state-level employment, state-level real GDP growth, and US real GDP growth are at or above their long-term historical averages."
"As Table VII reports (in Column 3), the coefficient on the main effect, which measures the response of firms in states during high unemployment times, is actually positive (albeit insignificant). Meanwhile, for firms in states during low unemployment times, the interaction term is -0.024 (t=2.17) larger, which indicates that the negative impact of seniority shocks on corporate employment is concentrated at times when the supply of employable labor is scarce." 
"This result can be interpreted as providing evidence consistent with the view that government stimulus crowds out private sector employment when the economy has little slack in the labor market, but does not when the economy is experiencing significant slack in the labor market."
Here is where they admit that when unemployment is high, stimulus raises their metric of firm employment and GDP, even if most of the money is going to government jobs. When unemployment is low, government competes for private sector jobs, and so their measurement of "firm-level" employment goes down. But they do add on an analysis of aggregate state data, which shows overall employment losses resulting from a political stimulus. Insignificant statistically, but negative. Why would that be?

They make a snide parting comment about West Virginia in their conclusion. But that state was plenty poor before the modern age of pork, so they were hardly thrown into some dark age by their success in the political pork-stakes. Other explanations are needed. Perhaps pork tends to entrench existing corporate as well as political interests, sapping innovation and growth in favor of rentier behavior.

It is interesting to note that the paper's tip-off word is "leisure", (appearing nine times), which is the alternate to economic productivity, implicitly stigmatizing workers. But "rentier" might be a far more accurate description of what is going on, since it isn't the poor who are choosing laziness and non-investment in response to federal injections, but the rich who are choosing political money over market money in this model.

Indeed, they are remarkably vague on the mechanisms that may lie behind their findings. The one concrete illustration they offer is the state of Senator Richard Shelby, Alabama, which netted 96 million dollars more earmarks as of his ascension to chairmanship of the Senate Select Intelligence committee. One Alabama company, building trailer homes, saw a decrease of 30% in its employment, which CCM explain as perhaps due to the $15 million that Shelby brought in for the actual stick-construction of low-income housing, hitting the related market for prefab homes. Nowhere do CCM account for the jobs added (or lost) in this other construction business.

So one might model the findings by proposing that classical theorists know particularly well of what they speak- that the business class is prone to laziness and rent-seeking, not the working class. Working people need jobs without fail, and look for jobs that fulfill basic desires for a decent life. The business class also looks for income, but this can be from passive investments or higher margins just as well as from new business creation. If they get the former handed on a platter, then why create new businesses? What if corruption pays better than trade & innovation?

None of this really speaks to Keynes. Yes, government spending is inefficient, particularly the ear-mark kind of spending that this paper deals with. But the authors themselves say that when labor markets are slack, the extra spending is not at all bad, and since they do not poll public sector or privately held companies, they may be missing a good deal of growth.

Note that what this analysis also says, in essence, is that the higher one taxes those "job creators", the harder they work. Which stands to reason, but isn't the story we have been hearing for the last few decades!


"Balancing the budget by drastically cutting spending and raising revenue was what the economy needed. “Nothing will put more heart into the country,” Hoover said."
  • Bonus economics figure. We need a carbon tax, and just how much carbon tax do we need? (An analysis focused on the nuclear industry.)


Saturday, July 7, 2012

Poisoning the water

On lying in politics and in other places.

I have been reading an interesting book about the evacuation of endangered Hmong from Laos after the CIA's not-so-secret war there against the North Vietnamese and the Pathet Lao. It had a passage about the Pathet Lao's tactics:
"The Laotian Pathet Lao yesterday accused Defence minister Sisouk Na Champassak of the Right-wing Vientiane side of planning a coup d'etat in Vientiane, the Khaosan Pathet Lao news agency said... The agency charged that 'Sisoul Na Chamassak, Minister of Defence of the Provisional Government of Laos, and a number of high-ranking officials of the Vientiane side secretly met on May 3-4 at milestone 27 in Vientiane to map out a plan for a reactionary coup d'etat in the neutralized city.'" - quoted from the Bankok Post, May 11, 1975
This was as the Pathet Lao itself was overrunning the country after the US threw in the towel in Vietnam. My (maybe uninformed) reaction was this was classic propaganda and disinformation, throwing out wild lies just to stir the pot, cow the opposition, and keep everyone off balance. The Pathet Lao have been in power ever since, as have the communists in Vietnam, (and Cambodia, with interruptions), keeping Laos miserable and committing what appears to be ongoing gencide against the Hmong.

It reminded me of similar practices here in the US, where the right wing hate media cooks up toxic media messages, and then "sees what sticks". Which is to say, what outrages listeners more at the intended target ... than at the message makers themselves for their lying and extremism. The swiftboaters were notable examples from a few years back, but this time they are sprouting like mushrooms- Obama is a socialist, is muslim, is not born in Hawaii. Death panels, job creators, Gun walker coverup, lucky duckies, debt bombs and prairie fires. Jesus loves you. The list is endless.

Such messages "stick" far more easily in an environment where a segment of the population is systematically lied to by its primary media, (FOX and talk radio). In the conventional media, messages that reach a certain level of saturation in the fringe are treated as worthy of coverage, indeed of he-said/she-said "balanced" coverage, checking the reporter's brain at the door in an effort to "teach the controversy".

This is how our public discourse is debased, and the problem is far wider than politics. Religions lie to their flocks as a matter of course. We don't bat an eye. Corporations lie to us in every advertisement, and in as many other venues as they can manage, pushing the sexy wonder of cigarettes, the green jobs brought to you by the oil industry, the work of god being done by your local Goldman Sachs employee, or the critical importance of paying their executives like kings. Indeed, the TV show Mad Men stands as the culture's wink and nod to its own debasement.

It is, in short, an unpleasant atmosphere to live in, a fog of deceit that is one of those things making the West a less than shining beacon to humanity. Yet we are raised with higher ideals. All teachers tell us that truth is golden, that we must never lie, and that George Washington never told a lie. They paint scholarship as a high ideal, an endless and richly rewarded search for truth. And then we land in junior high school, where reality sets in. Cooperation hits its limits in a war of information and disinformation, whose aim is power, not truth.

The Martha Stewart prosecution was, to many, hard to understand in this new context. Aren't federal agents lied to every day? Aren't we lied to every hour of every day? What was the big deal? Isn't truth mine to know and yours to find out? Isn't this whole "under oath" stuff a little antiquated? Indeed, don't we live in a post-modern world where truth doesn't even exist, deconstructed by French philosophers to a story that just expresses subjective views and interests, whatever the "evidence" may say?

It shouldn't be that bad, obviously. Free market economists make a fetish of information & truth being the real currency of the markets, with firms facing ultimate truths in their success or failure. True enough, but the need for truth reaches far deeper. The Soviet Union found out that, after the naked truth of terror ebbs away, if all one has left is a pile of lies, the society can not function.

Perhaps I am overly sensitive to all this, coming from the culture of science, where truth is more highly valued than in, say, politics, business, or theology. Truth is not always the highest value, in deference to civility. But it should always trump incivility, corruption, inequality, fraud, laziness, and greed. Society is not going to work if we lie to each other all day long.

A young Hmong refugee made an astute observation quoted in this book (my emphasis):
"In the picture above, I am the tall young man with a backpack on. This picture was taken while we were fighting to get in the U.S. C-130 to flee to Thailand as a result of the U.S. withdrawal from the Indochina War, which was and is still or will probably be remembered as one of the biggest and most historic losses in U.S. foreign policy regardless of its status as a world leader. There are a few major factors that contributed to this loss for the United States and its three allies, South Vietnam, Cambodia, and Laos. These major factors are corruption among all levels of government officials, lack of a solid and strategic national organizational structure, a wide gap between the rich and the poor people (which contributes to social, political, and economic injustice), and the lack of leadership with vision and wisdom who could understand world events and modify their policies accordingly for the good of the Indochinese and people around the world."

"One has to understand that the ongoing crisis is not a crisis of real poverty, but an organizational crisis. The world is like a ship loaded by the goods of life, where the crew starves because it cannot find out how the goods should be distributed. Since the depression is not a real poverty crisis, but one of organization, the remedy should also be sought through effective organizational work inside the apparatus of production and distribution. The great defect of the private capitalist system of production as it is today is its lack of planning, that is, planning at the social level."