Break (17 Dec – 6 Jan): Catching up on Sleep

Main health effects of sleep deprivation (See ...

The health effects of a sleep debt(Image via Wikipedia)

We all know how the school session goes: you stay up late doing homework, chatting with friends, going out, cruising the Internet, whatever. If you’re like me, grading, planning, playing with my daughter, talking with my wife, trying to maintain some level of sanity. Whatever you’re doing, the upshot is that you’re not getting as much sleep as you need, right?

And, we all know how much a teenager needs to sleep every night, right?

And, we all know when our circadian rhythms render us at our lowest ebb when sleep is most likely, right?

Well, now that he Winter Break is upon us, it is a good time to catch up on sleep because I’m sure that we’ve all run up quite a sleep debt, a lack of an adequate amount of sleep to support optimal functioning. This debt can be paid with a few nights of good sleep. I hope your sleep debt is paid now.

Along with this concept is REM rebound where you experience an increase in REM sleepbecause of a reduction in REM-sleep. While the lack of REM-sleep can be caused by almost anything, one cause is a lack of sleep of any kind.

It seems to me that this makes a great blog topic for the break.

Week 6 (21 – 25 Nov): Perception

This has been a busy week. Much busier than I had anticipated, but not too busy that I haven’t had time to think about perception. The biggest problem with this section is that it has so many little perception rules that it seems unruly. Thus, the visual notes, the two assignments, and other ways of organizing the information.


Image via Wikipedia

One of my favorite things about the unit is that it is so accessible in our daily life. Nearly every time you travel through traffic, you can identify perceptual laws. And, if you are out at night, you can see how they can go awry. For example, I was running the other night and on that dark stretch in Phu My Hung over by the Korean International School, I saw a car coming towards me. I was momentarily alarmed when I saw that its right headlight had come unattached and was heading right for me! The car seemed to be literally expanding right before my eyes. Then, I saw that it was simply two motorcycles whose headlights had traveled more or less at the same height for several meters giving the illusion that they were joined: law of common fate, law of proximity.

But also their sizes and heights acted as cues. Two objects that are the same size are seen as being the same distance while a smaller object is perceived as farther away than a larger object. Two objects that are the same height from the horizon, or in my case just the same height since there is no horizon at night, seem to be the same size while an object closer to the horizon is perceived as farther away. Thus the two headlights seemed to be the same distance and thus strengthened the impression of their proximity and their common fate.

In addition, top-down processing suggested that two headlights would be from a car. Of course, where I’m from there are more cars than motorbikes, so I wonder if it would be the same for y’all coming from a land of many motorbikes and few cars. Perhaps that is something to blog about or comment on.

Binocular depth perception cues are much more difficult to have casual experiences of; you have to do things to give yourself the experience. For example, look at something and close one eye and then the other and watch how it jumps back and forth. If you can get closer then you can compare the degree of jump as you close each of your eyes. This would be a demonstration of binocular disparity. Is this top-down or bottom-up processing? Again, comment or blog.


Sensory Things!

Our new unit brings up a storm of new vocabulary & concepts. Many of them are difficult to understand. I want us to concentrate on the basics for now & in the spring we’ll get deeper into things. My previous post addressed some of the confusion that exists in the transduction-sensation-perception process. Now, let’s turn our attention to what happens when sensation reaches the brain.

I give you these possible blog post prompts:

  1. After reading through the material on sensory adaptation, I found myself wondering if it were the product of the receptor cells located in the sensory organs or a product of a certain part of the brain. Perhaps you could answer that question in your blog: what brain structure is responsible for sensory adaptation? There is only one right answer. You must use your knowledge of brain layers & structures to answer it though.
  2. As the textbook contains this question (p. 114), “Do you see why it’s not a good idea to listen to interesting music while you are studying?”  I like this question. Most of us have tried to study while listening to favorite music, but have been distracted. I find it easier to study in a slightly noisier & chaotic environment like a coffee shop or my study hall, but more difficult to study in silence, at home, or if it gets too  loud. My blog prompt for you: (a) what is the answer to the author’s question, (b) where is it easier for you to study? & (c) what is happening when environment mental noise becomes distracting? All three questions are essentially the same.
  3. We’ve looked at two aspects of thresholds so far, absolute threshold & difference threshold. Those are relatively straightforward in their meaning. However, when we get to signal detection theory, the author notes that “the classic theory of thresholds ignores the (perceiver)”. In a blog post, you could explore the relationship between perceiver & sensory thresholds. What aspects of your physical or mental condition or the environment have you noticed in your experience as a perceiver make a difference in your personal sensory thresholds?
  4. Lastly, the textbook covers subliminal persuasion on pages 116 – 117. What do you make of subliminal persuasion? Why is it included in a chapter on sensation & perception? What was convincing to you in the section?

I look forward to reading your thoughts on these issues or ones that I haven’t thought of yet! Surprise me with your insights & reactions this week.