Get Aeolian

I've been listening to Major Lazer's song Get Free a lot recently. If you haven't heard it before, here's the music video:

After playing the song a dozen or so times in a couple days, I figured it might be worth learning how to actually play it. I've only just started trying to play along to it by ear, but it's already becoming pretty clear that there's some interesting stuff going on.

For one thing, this song has one of the simplest chord progressions imaginable: G-A-Bm-G. That's three chords for the whole song (and they're easy enough chords that I could actually play them on a guitar, if I had a guitar).

So if there are only three chords, what makes the song interesting? As with a lot of electronic music, the timbre of sounds is important: the echoing, bouncy, electronic part contrasts with the vocal cries. It's also strong lyrically (at least I think so, "feeling like a battery hen" is a great simile). However, I think that even when you only consider the pitch of notes in the song it's still interesting, so the question is: how does that work?

It turns out that "Get Free" is a textbook example of the Aeolian mode (on B) [I started writing this post because I initially thought it was in Dorian, which would have been neat, because I don't know any popular Dorian mode songs; Aeolian is a bit less exciting, but oh well]. That means it's melody is formed from the notes B, C#, D, E, F#, G, and A. This mode is also known as the natural minor scale, since it's a minor scale without the raised sixth or seventh you'd get in the harmonic and melodic minor scales.

Because the natural minor scale is the exact same as the harmonic and melodic minor scales when the sixth and seventh are avoided, the melody simply sounds minor as long as these notes are avoided. However, the chord progression begins and ends on a G major chord and G is the sixth. The second chord in the progression is an A major chord and A is the seventh. Three quarters of the chords in the song are thus major, but they always lead up to the B minor chord before falling back to the G major. Note that in the G-A-Bm-G progression, the root of the chord rises by a whole tone between each of the first three chords which conveys a feeling of growing excitement or momentum, but that momentum is stopped by the minor third chord and we return to the familiar G chord which is repeated once before the chords rise again (and again, for the entire song). The result is sort of an optimistic sound that has been infused with melancholy. The chord progression is constantly rising; constantly retreating.

While the chords progress by rising a tone at a time and falling back, the melody consists primarily of downward runs. At one level, this provides a contrary motion to the bass line since the bass follows the rise of the chord progression. The rise and fall of a melody line also shapes the emotion conveyed by the line; although this isn't as straightforward as up=happy/down=sad. Loosely speaking, the downward parts deflate tension, while the upward ones increase it. My interpretation of the effect this has on the song is that the downward runs convey the sensation of lowering expectations or accepting circumstances, while the upward movements ramp up tension and express a desire to fight back.

Getting back to the use of the Aeolian mode in the song, the seventh (the A) is particularly important for the melody. Normally, you'd expect the melody to resolve to the tonic (B) after hitting the seventh (A), but that usually doesn't happen here. There are quite a few lines that end on an A at the same time as the G major chord is being played ...and that too is unusual. The G major chord contains a G and B: since the A falls between these two notes, the result is highly dissonant and strongly suggests that the melody should resolve to the B. This is often what's happening when the vocal part does its howling thing (for example, when the word "friend" is said in "how long, how long 'til we have a friend"). Not all of the "howls" use this technique ("dreams" in "what will I do without my dreams" is actually sung on a B, but the layered vocals add surrounding notes to create the same dissonance).

The upshot of all this is that it is technically a very simple song, but the techniques it does use are used brilliantly. The simpler a song can be while still remaining distinctive and evocative, the more likely it is to be memorable.

PS. Yes, this is the same Major Lazer that created "Pon de Floor", which is known for its absurd music video featuring daggering. Before you go Googling that, note that Wikipedia quotes some guy as saying "'Pon de Floor' seems equally as offensive as watching porn on hallucinogenic substances" so it might not be the sort of thing to watch at work or around your grandparents.

Popular Neuroscience

This is a personal blog, it is not necessarily a reliable source of information.

I don't normally talk about the work I do on co-op terms, because I don't want to accidentally offend my employers by telling everyone how horribly nice they all are or making the similarly unfortunate error of posting confidential information. However, as I'm currently working for a neuroscience lab and it is pretty awesome I figure it couldn't hurt to write a series of posts about neuroscience stuff. Now, having said all that, here's a confidential training video:

Okay, so that video wasn't actually confidential, but I did steal the link from our lab forum. Now, Cleese's talk is pretty advanced (though quite entertaining), so I'm going to take a step back with a short Q&A (I'm not one to pass up an opportunity to talk to myself).

Q: What is neuroscience?

A: It's the study of the nervous system, nominally. In the long run, neuroscience, psychology, cognitive science, biology, and computer science are all intricately linked in a crazy quest to understand the way we think, the way intelligence and information processing in general works, and how it all somehow works with physical, biological components.

Q: Is neuroscience really that similar to cognitive science? Isn't it really just biology, but concentrating on the nervous system / brain?

A: I'm not very good with all the research classifications in the area, but it seems like most of what's being published under the label of neuroscience is neurobiology. From an experimental perspective this certainly makes sense: the brain is biological, after all, so obviously a substantial amount of the work being done in reverse-engineering it involves biology. Ultimately though, we're largely interested in the functionality of the brain and the way it gives rise to the interesting, complex interactions we all know and love: calling this functionality 'cognition' and attempting to understand said functionality is more or less what cognitive science is about. There is a big gap in understanding currently between neurobiology and cognitive science which is (to grossly and incorrectly simplify things) what theoretical neuroscience is puzzling over.

Q: tl;dr

A: Grr. Ok, look: biological understanding of brain = improving, but massively, insanely complex already and not capable of explaining brain function. Cognitive science = good at finding ways to do specific things; lacks general theories and can't compete with real brains. Gee, it sure would be nice to have people working on some combination of the above things! Those people would definitely deserve enough funding to pay their co-op students. Big time.

Q: I'm not convinced. What's the point of taking multiple different (and possibly conflicting) approaches?

A: First, which one's 'right'? I dunno. That's pretty much answer enough: they both provide more information, thus they're both valid approaches. If they happen to conflict, even better: there would then be an opportunity to investigate and fix problems that are found with the theories. That's pretty much how science works.

Q: Fine, fine. You can start at either the biology or psychological/cognitive levels, I get that. How could you possibly work from the midpoint between the two levels outwards?

A: This conversation makes more sense when it's less abstract. Instead of talking in terms of a 'midpoint' between two different research areas, I should really have framed this as a need to go beyond current empirical biological data to build more functionally complex models. Instead of making hypotheses based solely on raw data, you can start making predictive models constrained by assumptions, information processing requirements, simplifications required for tractability, and so on...

Q: Sorry to interupt, but isn't this post way too long already?

A: Yes.

Philosophy of Mind — Part 1: Qualia

I really wish I could say that what you are about to read is a well-thought out dissertation on such deep and intellectually stimulating topics as human consciousness, the biological basis for memory, and neural representations of meaning, but as you can probably tell from the sketch above, this post is more of a lark than a serious attempt to explore philosophies of the mind. Still, it's a topic I find pretty interesting so hopefully this will degenerate into a more worthwhile stream of consciousness post than my typical rant.

Disclaimer: I might at times make claims in this post that make me seem like I have a clue what philosophy of the mind is about. This is the internet, however, and I don't cite any sources. Reader beware.

Qualia are probably as good a starting point as any other. The word 'qualia' (pronounced kwalia, presumably after quality) is a term that describes — and you may want to brace yourself against the forthcoming hand waving — the subjective essence of an experience, the quality of a conscious sensation, the purplishness of purple being one example (although the "redness of red" is a more common example). At first, qualia don't seem to be overly interesting: it's hardly surprising that I can perceive redness or purplishness, or any of the other sensations I'm equipped to perceive, but the idea behind qualia is not simply that I notice when objects are purple but that this perception evokes a unique sensation that I can only appreciate due to my consciousness (and that a video camera would therefore not experience upon seeing the same purple).

You can almost feel that purplishness oozing into your mind, can't you?

If you're anything like me, qualia still probably seems like a somewhat esoteric and possibly useless concept at this point. It's loosely defined, not exactly a testable quantity, and seems to succeed mainly at evoking thoughts of sensations instead of helping to understand the process behind these sensations. So why have I spent so much time talking about qualia? Because the idea that every experience has this property, qualia, that is so familiar to us and yet indescribable is both extremely pervasive and influential. Dualism, the belief that thinking, intuition, sensation, and logic are made of a mind-substance that is completely different from physical matter is one attempt to deal with preconceptions about qualia. Dualism is generally discredited these days, thanks to science's proclivity for materialist theories, but I'm probably getting ahead of myself. The point is that consciousness is such a complex process that we have a catch-all term for the mindbogglingly indescribably properties of everything.

It's now getting to the point where I'm experience the sensation of sleepiness in an intrinsically indescribable way, so I'm going to have to wrap this up abruptly. Clearly, I haven't done this topic justice, but if you're moderately interested then Eliasmith and Hofstadter (among many other) are interesting guys to check out. Also, this page about qualia inversions (à la inverted spectrum) is a better introduction to the way the term qualia is actually used by philosophers.

Oookay. Sleepy times.