Thursday, November 19, 2009

Granger Causality

Who knew psychology would involve so much math?! Also, I'm glad I had conceptual understanding of Bayesian statistics (and prior probabilities) before I started learning about functional connectivity.

If you understand any of the above paragraph and are not a grad student or mathematician... go watch Mad Men or something.

Lecture Notes

For the approximately 0 people out there who are curious. Here is a snippit of my lecture notes from my last lecture. The paper copies I have are covered in scribbles and examples of things like "Too much GH = GIGANTISM" and "Talk about giant confederate soldier and his giant Canadian wife!" For the following segment of notes, I wrote things like, "Extended estrogen treatments not recommended by AMA- Not really useful for men."  Most of the grammar in these notes was put there as I was going through the material the morning of class. I didn't really read from these as I was talking, mostly I was writing on the board and getting chalkdust all over my pants.

This is about a 5 minute stretch about neuroplasticity in the hippocampus:

III. The Hippocampus
  • As we talked about on Wednesday, the hippocampus is a major target of stress hormones. However, cortisol is not the only hormone that affects the hippocampus.
  • Cortisol- We have already talked about how cortisol leads to hippocampal atrophy. What does this mean? Basically, the hippocampus shrinks.
    • Chronic (or even acute) exposure to high levels of cortisol can cause death of dendrites in the CA3 region or the hippocampus. The hippocampus has 4 major layers (CA1-4).
    • Cortisol in the dendate gyrus stops neurogenesis. Neurogenesis is the production of new neurons. This process continues as we age and is thought to be involved in some of the more general forms of plasticity discussed earlier.
    • These two changes can lead to memory deficits- underscores the importance of the hippocampus for learning and memory.
  • Estrogen and Progesterone- I mentioned on Wednesday that they had protective effects…
    • When given in appropriate amounts, these hormones have been shown to increase the number of synapses (cell connections) in the CA1 region of the hippocampus.
  • This synaptogenesis seems to occur via the NMDA receptor (N-methyl-D-aspertate).
    • NMDA is a glutamate receptor and is thought to be the major way to affect plasticity via the growth of new synapses.
    • Estrogen upregulates production of NMDA
  • How does it work? In the post-synaptic cell, the NMDA receptor will only become active if both the pre and postsynaptic cells are active at the same time. By acting as a coincidence detector in this way, NMDA helps in the formation of neural networks.
  • Reversible atrophy in CA3
    • This occurs mainly in ground squirrels and in other small rodent like mammals.
    • This occurs during hibernation.
    • This is very similar to the atrophy seen as a result of stress. However, this occurs much faster and is generally thought to be reversible.
    • The mechanism of this is not really understood.

Paranormal Activity

Though this featured some interesting bits of suspense, I literally laughed out loud when it ended.

While watching Paranormal Activity, I was less interested in the story and more interested in how the film managed to build suspense through incredibly simple means.  Loud noises and doors closing unexpectedly led to some gasps of terror from some people in the audience.  Had the film stuck to these simple things, I think it would have turned out better.  By far the weakest points of the film where when it lapsed into exposition and horror movie cliches.

I mentioned that I laughed out loud at the ending.  Not only did I find it completely ridiculous, but was a complete violation of the rules the film had set out for itself.  Any sense of realism established by the Blair Witch Project style cinematography was completely negated in the last 30 seconds of the film.   Honestly, it ruined the whole thing for me.

The Men Who Stare at Goats

Without such an amazing cast, this would have been pretty lackluster.  Definitely not the best movie of the year, but worth watching on DVD.

There is an amazing bit of meta comedy in this where George Cloony explains to Ewan McGregor what it means to be a Jedi knight.  However, aside from some amazing casting choices including Jeff Bridges essentially reprising his role from The Big Lebowski and Kevin Spacey playing a sociopathic psychic, the film never really fulfills its comedic potential.  There are some hints of a criticism of the excesses of military intelligence and the whole thing plays like a condemnation of the Iraq war, but neither of these things is fleshed out in a satisfactory manner.  Still, I'd recommend seeing this on DVD (or on student discount Thursdays), if for nothing else than for George Cloony's impeccable comic timing.

Where the Wild Things Are

Aside from maybe Inglorious Basterds, this was my favorite movie of the year so far.

Seriously, if ever there was a movie made to fit my very specific taste this was it.  There are monsters running around, weird things happening that aren't ever explained, the direction and cinematography are amazing, and the soundtrack is performed by a band I really like.  The feeling I get is that this is a bit too quirky for everyone's taste, but I really really enjoyed it.

Anatomy of a S.D.I.

There are several teaching requirements that I need to complete in order to get my degree.  The first of which is known as Supervised Direct Instruction (S.D.I.).  Essentially this is the same as a normal T.A. assignment but with some additional responsibilities.  Principle amongst these is that I have to do about a weeks worth of lecturing under the supervision and guidance of a faculty member.

I was planning on doing my S.D.I. next semester with my advisor and then doing my other requirements next fall (which would put me right on track to graduate on time).  However, my advisor and the professor I T.A. for colluded to convince me to do it this semester, for a class on hormones and behavior.  I didn't really object to this as normally the lecturing done by the T.A. is from the professor's notes.  Generally the professor and the T.A. work together extensively to ensure that the T.A. is ready and that the lectures go as smoothly as possible.

Well, I've just finished two weeks of teaching without any supervision whatsoever and I think it went pretty well.  I had to build three lectures from scratch, write a quiz, assign a reading assignment (from an academic journal), and write a set of open response questions.  All this without a textbook or anything resembling guidance.  Oh, and I was also expressly prohibited from using powerpoint (though I generally prefer to lecture unplugged anyways).  I'm griping here, and I was complaining to anyone that would listen earlier in the week, but mostly I'm just amazed it didn't turn into a complete disaster.

As far as the lectures themselves... I still need to work on some basic teaching things like talking slower and giving time for student questions.  Also, I need to work on not leaning back on the blackboard when I'm wearing a black shirt.  I finished each lecture a little early but no earlier than five or so minutes before the end of the class period.  I got stuck a few times with student questions, but it turns out saying "I don't actually know that, thats a good question." generally satisfies undergraduate students.

Overall, I think I managed to do alright.  Given how helpful she was during the rest of the process, I probably won't get any feedback from the professor so I won't know anything for sure until I get the teaching evaluations back from the students.  The one benefit of all this is that my advisor went to bat for me and had it out with this professor about making me do so much work without any direction.  This didn't really help the situation per se, but its good to know that she'll do that for me.

In terms of the students, the quiz and reading assignment grades are higher than normal despite numerous complaints about their difficulty.  No one came to my office hours while I was teaching, which I'm taking as a sign that my lectures were at least comprehensible.  And now, after months, everyone recognizes me as the T.A.

Like seemingly everything else in grad school I'm learning by jumping into the deep end.  Next semester I'm teaching a section of a research methods class.  Thankfully, I get to choose my own textbook and there will be a faculty member overseeing my progress.  My S.D.I was probably good preparation for this, but mostly I'm just thankful I don't have to explain the hormone changes that occur with aging to a bunch of undergrads again.