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.

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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.

 

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Week 3 (31 Oct – 4 Nov): Sensation & Perception 1

Sensation & perception is one of the most fascinating topics in psychology, both for the beginning student & for the professional psychologist, because it addresses one of the most fundamental issues of life: how does information from the world get into the brain & then processed to make meaningful information. When you think about it, the brain does not perceive or sense anything. It only receives electro-chemical messages from the sense organs. Everything we experience in the world comes from this process.

  1. Over the next few days, we will cover some very hard concepts:
  2. How sensation becomes meaningful
  3. How sensation is filter to be manageable
  4. How each of the senses work (eye, ear, nose, tongue, skin, & balance) — Yes that is six!

As far as something interesting to blog about, I think that the vestibular sense or balance is it. Most of us believe that the sixth sense is ESP (extra-sensory perception), but it is not. It is our sense of balance. Our balance gives us information about the world just as much as our eyes give us information about shapes, color, & texture; ears, sound; nose, scent; tongue, taste; or skin, temperature, touch, or pain. Without a sense of balance, our lives would be greatly impaired just as they are if we loose any of our other senses.

Think about it. If you could not balance, you could not walk, sit up right, or even lie down. You would constantly feel dizzy and have the sensation of falling. Someone like me that gets motion sickness easily would be constantly nauseated. It is little wonder that people who loose their sense of balance have the highest suicide rate of any group that looses a sense.

That’s right, people (a) can loose their sense of balance & (b) it is so disturbing and difficult to compensate for that these people commit suicide at a much higher rate than those who are blind, deaf, cannot smell, cannot taste, cannot feel pain, cannot feel sensation, or cannot sense temperature. And, some how we are completely unaware of our sense of balance.

Just to whet your appetite, and hopefully, get you to return to this blog, I will blog about a case study of someone who lost her sense of balance & was successfully treated for it! Check back soon for that exciting & interesting update!