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Friday, August 29, 2008

A Parent's Right

I read this article this morning and it made me wonder: where did the concept that it is a parent's right to choose how his or her child is educated come from? After all, that isn't entirely true. As I understand it, children are required by law to attend a school, and if a parent cannot afford a private school, then that school must be a public one or home-school. Therefore, the right isn't a complete one anyway. The parent has no right to say, "I run a farm, and I want my kids to grow up to be farmers like me. They don't need any of that fancy schooling, they just need to stay home and learn how to work the farm equipment." While home-school is an option, there are still certain requirements that must be met. Enforcement of those requirements is an issue in and of itself, but there is still the precedent that the state dictates that a child needs to be educated in some manner, and a certain amount of that educational requirement is specifically outlined. Since that has been accepted, I am not sure what right is being violated by changing the standards of required education to become more rational and secular. Of course the argument can be made that the right to religious practise is being violated if teaching one's religious doctrine as fundamental truth is a vital tenant to one's faith. Yet that is the crux of the whole right to religious practise - depending on how one defines religious practise, virtually any law or ruling can be interpreted as violating one's religious rights. No one tries to make the argument that sanctified murder through ritual sacrifice is a valid exercise in religious freedom in our modern society, even if ritual sacrifice is a fundamental tenant to one's religious practise. It is therefore seen that there are and must be limits on the right to religious practise, which immediately draws the questions of what are those limits and who gets to decide on them? It is this amorphous nature to the right of religious practise that, to me, makes it fundamentally untenable. It would seem indoctrinating children with religiously based education is a greater violation of the children's right to a proper education aimed at giving them an equal opportunity for participating in society than it is a violation of the parents' right to choose the content of the children's education.

(In a related issue, I have always thought it a little bit unfair that a person's anathema toward a particular object or behaviour, if under the blanket of religion, is given more credence than another person's individual loathing or obsessions. This is particularly troublesome when there is no way to measure the degree to which a person is invoking his right to avoid a particular action or practise based on religious reasons actually cares about the religion in question)

I know this fairly outside of my purported subject matter of science (with an emphasis on computational neuroscience), but I thought it was worth writing about. I know I've recently told some of less-computer savvy relatives about this blog, so I'd like to point out that it is possible to leave comments if you think I've come to erroneous conclusions or made false claims (or if you agree with me and would like to shower me with adulation).

Monday, August 25, 2008

A dearth of posts

Just thought I'd make a note of why there have been so few posts lately... I am visiting my parents. That means sometimes spotty internet connection, lots of alcohol (although never an inordinate amount at once), an endless supply of cherries, wrestling, and game playing. What that ultimately ends up meaning is I don't spend a lot of time on the computer, and hence I don't do much on my blog. Just in case readers were getting worried... I will be back in Toronto later this week.

Saturday, August 16, 2008

A short note while enroute: Movies!

I am currently in the Calgary airport killing time before my last flight (this one is just a short hop over the mountains to get me almost home... just an hour and a half drive after that. Oh, the joys of coming from a puny little mountain town without a commercial airport). I almost watched two movies on my flight from Toronto, but unfortunately the second one got cut off with only twenty minutes left. Anyway, I finished Vantage Point, which I have to say was a remarkably disappointing movie. It had a few minutes in the middle that were good, but by the end I had a distinctly disappointed feeling.

The second movie I started watching was The Bank Job. It was enjoyable in that it wasn't a typical heist movie (like I originally thought it was going to be) where the whole plot revolved around the job itself, but instead was a much more interesting fictional-historical movie where the main plot had to do with the ramifications of the crime in relation to the multitude of conflicting motives belonging to the different conniving parties. Also, I enjoy Jason Statham as an actor. I'm not particularly sure why, since he has been in some pretty bad movies as well as some good ones, but he has an enjoyable English charm.

Anyway, I'm going to watch some news about the Olympics now, and then go and catch my plane.

Tuesday, August 12, 2008

Political Science Review: Thucydides

Monday night marked the end of my required social science credit. I had my final exam for POL200Y1 - Political Theory. I actually quite enjoyed the course, though I discovered that I hold some of the most famous thinkers in history in contempt. Perhaps that is a mark of extreme arrogance on my part, but I suppose I'll have to live with it. I have been meaning to write some thoughts about the course for a while, and so I decided that over the next little while I will try to give a brief review of the works that I read from each of the authors we looked at: Thucydides, Plato, Aristotle, Cicero, Machiavelli, Hobbes, and Locke (in chronological order).

Thucydides was a slightly odd first choice of author, as he is the only author whose text we looked at was not specifically a political text, but was rather historical. However, his text had many political overtones, as he directly states early on that the point of his history is to look at the nature of man, for men cannot know their nature without understanding their history. The specific history explored by Thucydides is the Peloponnesian War. A more complete history of the details of the war can be found on Wikipedia. Though containing political points, Thucydides is primarily a critic. He offers no concept of how things should be fixed, he simply points out some of the failures of political systems at the time.

The war itself was mainly between Sparta and Athens, though it involved virtually all of Greece as the other city-states became drawn in on one side or the other. I think one of the most interesting parts of Thucydides is also at the very beginning just after he outlines his motivations for writing the history based on the unchanging nature of man. He states that, though it was largely unspoken, he thinks the main cause of the war was fear of Athenian power. Sparta at the time had the most powerful land army, with their infantry being legendary for their martial prowess (this was is only a few decades after the war against Xerxes and his Persians). Athens, however, is the primary naval power as well as one of the richest Greek cities. It also has the largest population and one of the first true democracies.

The text mostly consists of speeches and dialogues. This at first seems fairly strange in a historical text, but once you get used to the style it is pretty interesting. One of the most striking characteristics of the text was the strong parallel I saw between the Athenians and the United States of America. Athens, like the United States now, was a powerful imperial state with a distinct economic advantage over its rivals. Like the United States in the second world war, Athens served as an instrumental force in a war that was largely seen as noble and necessary for defeating a decidedly evil foe (the Persian invasion of Greece). Their success in stopping the Persians earned them a great deal of good will and respect, but also forced them into the political affairs of the whole region. The memory of the great war was now fading away, leaving those who now found themselves wronged by the imperial aspirations of Athens feeling embittered and resentful. Athens justified themselves by claiming that they had the right to elevate their standards of living through unequal treatment of subordinate city states because they were better. Theirs was a blessed way of life, more free and noble than that of their neighbours. They also made the argument that someone had to be on top, and they were better than any of the alternatives.

Anyway, I don't really have a lot to say about Thucydides other than he was interesting. If you find ancient history engaging, I would say he might be worth reading. Also, if you enjoy historical parallels to contemporary politics, he can be read in that manner quite easily. Perhaps my lack of things to say, though, might also rest in that I read him at the beginning of the summer, so many of the details are starting to fade. My discussion of the next six writers should be a little more engaging.

Thursday, August 7, 2008

A note about crackers

I believe most people reading this blog have heard about the whole eucharist 'stealing' business that went on in Florida a while ago, followed by the desecration of one by PZ Myers. Up to this point I have avoided comment on this subject simply because it seemed rather absurd to me and I plan to continue with the no comment policy. This is just a quick post to mention that even Hobbes, one of the founders of modern political philosophy, pointed out multiple times throughout his seminal work Leviathan that the concept of transubstantiation was utterly ridiculous and made absolutely no sense. That was three and a half centuries ago. I have many issues with Hobbes' conclusions (he is scarily totalitarian. In fact, I think it is specifically in chapter 19 that all of Hobbes' careful ruminations shockingly lead him to the nonsensical declaration that a despotic monarch is the best form of government). Actually, I seem to have lost the original point behind this post, but I think I'll put it up anyway, because I found it to be interesting tidbit of information. Hobbes is an odd character - sometimes nearly atheistical, other times he is arguing straight from scripture. I think it might be safest to regard him in a similar manner to Jefferson, in that he was raised in a Christian society but was intellectually frustrated with the contradictory and evidentially baseless nature of many of the church's teachings.

Saturday, August 2, 2008

Brain Waves

Since my recent Scientist Appreciation and its content regarding electroencephalography (EEG), I have received several questions about brain waves and just what they actually are. I think there is an incredibly common misconception about what constitutes brain waves and what said waves mean. To really answer that question, though, I should start with a basic description of the neuron, specifically the cortical pyramidal cell.

The cortical pyramidal cell is the 'typical' neuron. I have put typical in quotations because I don't mean typical in the context of it being the most common (that would be the granule cells of the cerebellum, as I discussed in a post a while ago), but rather I mean it in the sense that it is the cell that most people think about when a person uses the term neuron (at least as far as my experience goes). For a very basic diagram of a neuron, you can go here.

As the diagram shows, there are three main parts to a neuron: dendritic tree, the soma (cell body), and the axon. The diagram also displays the myelin sheath and the terminal boutons (it calls them buttons), but those are only tangentially pertinent to the discussion of brain waves. The axon is a neuron's main method of sending a signal, via what is known as an action potential, to a target cell. The dendritic tree is where most action potentials are received by a neuron, although sometime signals are also received on the soma - this will be important later and discussed in further detail. The junction between an axon and a dendrite is known as a synapse. Neurons generate a resting potential across their cell membranes of approximately -70mV with respect to the surrounding interstitial fluid. For a neuron to fire an action potential it must be excited to below some threshold. Exciting a neuron is typically caused by synapses in the dendritic tree, where an incoming action potential triggers a brief influx of positive ions (usually Na+) that causes a small increase in the local intracellular voltage. This spike in voltage is known as an excitatory post-synaptic potential (EPSP). Similarly, it is possible to inhibit a neuron (hyperpolarizing it), usually through an influx of Cl- ions. This is known as an inhibitory post-synaptic potential (IPSP) and tends to occur on the soma.

While I kind of glossed over some of the details, I hope the basic idea is clear enough: a neuron can be triggered to fire an action potential if it is suitably excited through EPSPs occurring in its dendritic tree in enough quantity (either spatially - a whole bunch of disparate EPSPs being triggered at once - or temporally - a set of EPSPs being repeatedly triggered in quick succession such that ion levels build up to the point that an action potential is triggered). However, this neuronal firing can be hindered by IPSPs occurring on the soma. Now that the basic electrochemical computing mechanism of a neuron has been described, imaging a whole set of these pyramidal neurons arranged basically like a forest of trees. The dendrites are sticking up like foliage, the soma and axon are spatially distinct below like trunks. Due to the propensity for EPSPs to occur in the dendrites and IPSPs to occur on the soma, a small electric dipole is created through the predominant flow of positive ions toward the dendrites and negative ions toward the soma. Though a fairly small dipole, since most pyramidal neurons are arranged in parallel within an area of cortex, the small dipole generated by each can function additively to create a potential difference that is actually large enough to be detected by an EEG electrode affixed to a subject's scalp.

By recording potential difference between to distinct points on a person (a reference electrode and another electrode), a voltage can be determined, amplified, and output to either a computer (more modern) or a paper recording device (what they used to do). The reference electrode placement is actual a point of some contention, as typically a researcher wants a neutral electrode, but that is virtually impossible to find. Typical choices for reference electrode include the centre of the forehead just about the eyes, the back of the head, and the neck. This potential difference between the two electrodes tends to oscillate with varying neuronal activity. It is this oscillating activity that is referred to as a brain wave.

The amplitude and frequency of the oscillating potential difference can relate information about the general state of a subject's brain, as well as help to identify some specific pathological conditions. I do not know a lot about the clinical applications of EEG, but in terms of things like reading other peoples' thoughts and other such pseudo-scientific crap that it simply doesn't make sense. It is impossible to know where in the brain the sources of an EEG signal come from, so it cannot even be used to identify for certain the region of the brain doing cogitation, nevermind specific neurons.

That is a basic review of what brain waves are. I hope it all made sense, but it is hard sometimes to gauge what is basic knowledge and thus doesn't need inclusion, and what needs further explanation for someone who hasn't studied something for a while. I'm not feeling particularly eloquent at the moment, however, so I think I ought to end here for now.