Absolute Threshold Demo

Today in class we'll be exploring basic principles of sensation, including absolute thresholds.

When prompted, check out this interactive demo on absolute thresholds in order to build your understanding of this concept.

Studying for Your Sensation and Perception Test

By now you've probably noticed that, although this unit doesn't contain any more vocabulary than previous units have, the major challenge it presents is that so many terms and concepts seem to be only separated by subtle differences. And, given their abstraction, writing about them (like on an FRQ...) can be a challenge because of the sophistication of the description required.

So...let's get started reviewing! Here is a handy list of study tools that may help you in your efforts:

• First, remember that our Study Session for this Unit is SUNDAY, November 15th at 5 PM. Because we've been struggling with space issues in the past, I've moved this one to the CAFETERIA. Here are the links to the study session materials used tonight!
• Slide Show (many folks requested that I share this link; I'm posting it here to save time).
• Which One Doesn't Belong exercise, and answers. 
• Practice FRQ
• I will also keep the final Socrative questions we did at the end (15 new ones) up tonight if you want to practice. Just visit m.socrative.com and enter room 109495 to try them.
• You should have a list of the Unit Objectives for Sensation and Perception. You will want to be prepared to do any of the tasks listed on that handout!
• Don't forget to brush up on that vocabulary! Quizlet can help make sure you don't miss anything.
• Carefully review that list of Confusing Term Pairs from this unit. Can you describe how these things are kind of the same YET different from each other?
• If you've already burned through the practice questions on the paper Study Guide you were given in class and are looking for more, here are some practice questions on Sensation and Perception.

Quizlet Flashcards


Basic Sensation and Perception Principles


Visual Process


Auditory Process


The Other Senses
Note...I may or may not use all of this in class. I'm contemplating a different activity for handling Module 21 content, so you might not actually view these slides in class. I'm posting them here in case I use them AND in case you miss Friday and need some way to access content covered that day.

PsychSim: The Auditory System

In order to review material from Module 20 and prepare effectively for class on Wednesday, you'll need to complete a PsychSim module on The Auditory System.

To access the module:

1. Go to this website.
2. From the "Main Menu" select Sensation and Perception.
3. Select The Auditory System.
4. Use the navigation buttons to move through the module, and complete the accompanying worksheet. 

Also, a reminder: Headphones will be helpful on Wednesday, since you'll have the opportunity to experience some auditory phenomena using your Chromebook.

Online Synesthesia Test & More Info

If today's discussion of synesthesia has you wondering whether this condition describes you, it might be helpful to visit http://synesthete.org/. The site gives more information about synesthesia research and provides online tests for different forms of synesthesia.

Study Tools for Sensation & Perception Test

I've thoroughly enjoyed this unit and its fun demos, but all good things must come to an end. For us, the end will be on Thursday as you complete your test on Sensation and Perception. Now, even though this unit is cool, I'll warn you that the unit test can be a challenge. There are a LOT of concepts and terms to remember this unit, so don't kid yourself about the amount of studying you'll need to do in order to be ready.

Here are some things you can do to help prepare:

• Quizlet flashcards - Remember, you should be ready to provide written examples or explanations of these things in your own words, so practice doing so!
• Don't forget that List of Confusing Term Pairs you received in class. Can you explain how these are similar to AND different from each other?
• More practice MC items: Sensation and Perception
• Crash Course Videos: Sensation & Perception, Perceiving is Believing, Homunculus Crash Course

Sensation and Perception Notes:


Vision


Audition


The Other Senses

Sensation & Perception Review Tools

Hi all!

With your Sensation & Perception test approaching rapidly, you'll want to take some time to review all of the terms, concepts, and theories from this substantial unit. In addition to the Study Guide you received in class, and the handout on commonly confused term pairs from this unit, you may want to use the links below to aid your review. Good luck!

General Review

• Practice MC Questions on Sensation - test your knowledge of Ch. 5 (sensation)
• Practice MC Questions on Perception - test your knowledge of Ch. 6 (perception)
• Quizlet Flashcards/Games for Sensation & Perception

By Topic

• How the Ear Works - a video review of ear anatomy & function.
• How the Eye Works - a little more in-depth than our in-class discussion, but still helpful.
• Video Review: Psychophysics 
• Absolute Thresholds - quick, online module
• Synesthesia Video - What is Synesthesia?
• Depth Perception - review video (includes several binocular & monocular cues)

Auditory Processes PsychSim & Sensation Activities

For Monday, you will be completing this homework assignment using the PsychSim 5 Module on the Auditory System. You will learn about properties of sound waves and how the ear responds to these properties to create our experience of hearing. Complete the ear diagram you received in class as you work through the module. Once you have finished the module, you may wish to play around with these fun hearing links:

• Test out your difference threshold for pitch using this online test.
• Check out this interactive module about the work of Georg Von Bekesy, a Nobel Prize winner who made important discoveries about how the cochlea works to allow us to discriminate pitch. You also get to play a game with this one. :)
• A fan favorite: the backmasking in music site. 

If you're still looking for more sensation-related challenges, here are a few we've used/talked about in class recently:

• This one allows you to test your absolute threshold for visual processing. 
• A color blindness test

Studying for Your Sensation and Perception Test

We will be wrapping up our sensation & perception unit tomorrow with a test on those topics, so that means tonight should involve some careful studying of the many (over 100!) terms and concepts we learned over the past couple of weeks. To help you, I've included some links and videos below.

How the Eye Works (a little more detailed than the version we used in class, but it does hit all of the major parts). For more info on this and other eye-related stuff, check out the National Eye Institute Website.


How the Ear Works


For your entertainment as you review all those depth perception cues: SNL Skit on No-Depth Perception Guy!



And, of course, we don't want to leave out our favorite vocab review tool: Quizlet. For your reviewing pleasure, all 105 vocabulary terms from this unit. Yikes!

Fun with Illusions!

At about halfway through the Sensation & Perception unit, we've seen a good number of visual illusions, and more will follow. I like to try to post links to sources of the ones I use in class, as well as new, interesting ones that students bring to my attention.

The one shown below is of the latter type. A student sent me the link, and I think it works by simulating stroboscopic movement (we perceive movement in a series of slightly changing static images). Seems like it would be fun to try using the links to print out your own! (Shown in the comments section if you view in YouTube.)



Also, back again this year are the holophonic illusions that exploit stereophonic hearing and the results of the Visual Illusion of the Year contest held by the Vision Sciences Society. Embedded below is the 2012 contest winner, which shows a device that creates the convincing illusion that one's hand has disappeared! Unfortunately, the video has no accompanying sound, which made me question whether my computer's speakers were working for a moment (that was probably not an intended part of the illusion).

Thresholds & Subliminal Sensation

Today in class we explored absolute and difference thresholds, particularly as they relate to "subliminal sensation." I usually have quite a few students interested in exploring these things on their own, so to that end here are the links to the musical backmasking site we looked at in class and another that examines "reverse speech" in recorded speech. As you probably can guess, based on the psychological research about subliminal messaging, I don't give a whole lot of weight to the claims made by some of the authors of these sites, but you should feel free to explore them on your own in light of the research we discussed in class.

And for fun...this video clip from the popular Monty Python series pokes fun at the inconvenience of working with people who have varying absolute thresholds for hearing. Thanks, Nathan S., for passing this on.

Vestibular Sense & Dolphins

While hunting for information in response to a student question (the best type of prompt to get me thinking!), I happened upon this interesting post on the vestibular sense of dolphins from the Dolphin Communication Project (DCP).

Is this a thinly-veiled excuse to share weird animal information? Maybe. But it does relate to psychology, particularly sensation.

According to the post, some evolutionary biologists believe dolphins evolved particularly small (and thus, less sensitive) vestibular systems as compared to other mammals because they have little need to be aware of which way is "up" in the way that land-based mammals do. Three times smaller than similarly-sized mammals, it turns out. Thus, they can now execute impressive barrel rolls and directional changes that would nauseate land-based mammals attempting to replicate them.

Of course, the original student question had nothing to do with dolphins, just motion sickness and weightlessness (which is addressed in the dolphin article to some degree).

If you're looking for a possible cure for motion sickness, this website on motion sickness offers a number of potential solutions, some more extreme than others. I was particularly intrigued by one strategy mentioned by the website: the "Puma Method," which unforunately does not reference the animal, but rather a NASA-employed Dr. Sam Puma. A video below...

Also, according to the website, those wrist bands for reducing motion sickness are probably effective only due to their role as placebos.

More Fun with Vision

Thank you to one of my students, Adam S., for alerting me to this video by the Blue Man Group. The title - Rods and Cones - is a big hint as to what sensory process the song is dedicated to.

Also, by request, here is the link to the Rotating Spiral Illusion, which is great fun due to its ability to generate a strong motion after-image.

Some Links from Class - Sensation & Perception

Today in class I shared a few links to sites that demonstrate principles of sensation and/or perception.

The Rotating Cat Illusion was a popular one. The cat appears to rotate one direction initially, but if you stare at it long enough it will seem to reverse directions. Different people have different initial perceptions of it (some see it rotating right, others left). This is a great illustration of how the exact same sensory stimulus can elicit different perceptions from people. A related illusion that you might be familiar with is the Spinning Silouette illusion, which is often INCORRECTLY described as a left/right brain personality test.

Note: if you are accessing this from school, the district's filters might block the cat website. Try Googling "spinning cat illusion" and maybe a site that you can access will be available.

For those of you interested in the backmasking and reverse speech sites, here are the links:

• Song Clips & Lyrics (forward & reverse)


• Reverse Speech (speeches and statements from public figures)

Another one...

Completed by our classmate Sally Mueller... the Sensation (Chapter 5) Quizlet!

See you Sunday at 6:00 PM for our review session! Featured topics include:

• Neuroscience
• Research Methods
• "All that Math Stuff" (standard deviation, descriptive stats)
• Learning (UCR, CR, etc.)

And the Winner is...

Emily S.! (And no...that's NOT her picture)

Emily was the lucky participant whose name was drawn to win the fabulous Therapist in a Box prize from last evening's AP Night festivities. Like many others attending, she participated in our mini-research project on facial recognition.

All participants were shown the image at right. They were asked to determine which of the two images on the left best resembled him.

Two-thirds of participants chose the lower image (labeled "B" on the wall chart used), while only one-third selected the top image. Neither answer is more "correct" because each is simply a composite image created by "mirroring" one half of the face in the original photograph. So why did people prefer the "mirrored" left side to the right?

Here's the presumed explanation: The right half of the brain is responsible for interpreting information from our left visual field (i.e. the left side of the man's face). It is also more frequently used for facial recognition and emotional interpretation. When you look at the two possible choices, the part of your brain that is most adept at recognizing faces detects a match in the lower photograph: "here's that same left side"! It does not see a "match" in the upper photo because your right brain was not studying that part of the original photo (that was your analytical left brain).

Of course, we can all "see" that the images are equally representative of the man. But thanks to your wonderful brain...it's not necessarily what we perceive.

The Tongue Map Myth

Many of my students are shocked to read in their psychology textbooks that the "Tongue Map" is somewhat of a myth, particularly because even some of their current science textbooks continue to print this misinformation. For the skeptical, here are some links to credible information on the subject:

• The Tongue Map: Tasteless Myth Debunked (from livescience.com)
• The Tongue Map: An Enduring Myth - introduces a more accurate diagram
• Tongue Myths Debunked; Frustrated Gradeschoolers Vindicated
• Really? The Claim: Tongue is Mapped Into Four Areas of Taste - NY Times Article
• I hate to mention this, but even Wikipedia doesn't buy the Tongue Map Myth

I'd have to agree with Christopher Wanjek, writer for Livescience.com's Bad Science Column:

"The degree of variation is still debated, but the kindest way to describe the tongue map is an oversimplification. Why textbooks continue to print the tongue map is the real mystery now."

Phantom Limbs

Today during our class discussions on sensation, a number of questions came up for which I had no readily available answers. The links I've put together below are an attempt to answer some of these questions.

1. Many of my students had questions about Phantom Limbs. This is a condition wherein an amputee still "feels" sensations from the missing limb (pain or otherwise). The tricky part about answering questions that relate to phantom limbs is that so much of the research is gleaned from case studies...so the question, "Would someone with a phantom limb feel ______________?" is hard to answer. It may be true of some patients, but not others. Or we might not have documentation of that specific situation within known case studies (but that doesn't mean it doesn't exist). The Psychology Department at Macalester College has a good site for further investigation. It provides a bunch of information on phantom limb patients, and examples of case studies on the phenomenon.
2. One interesting treatment for Phantom Limb Pain is the use of Mirror Boxes. Below you will find a video featuring Andrew Austin (a treatment provider from the UK) describing the use of Mirror Boxes in therapy. If you have a bit longer, you can check out a 2007 TED Talk by VS Ramachandran which describes the use of mirror boxes to successfully treat phantom pain (as well as two other types of disorders resulting from physical damage to the body).

Hearing, The Ear & Georg Bekesy

Today in class you will be exploring The Ear Pages, a site dedicated to Nobel Prize winner Georg Bekesy and his discoveries about the ability of the human ear to detect frequency (in sound waves).

When you finish, there are number of sites you might choose to explore, including some of the ones I have shown you in class over the past few days. The sound illusions work best with headphones.

• Holophonic Sound (sound illusion)
• Five Great Auditory Illusions
• The Counter-Rotating Spiral (motion afterimage)
• A Gallery of Visual Illusions (particularly good because the explanations are included)
• Another Blind Spot Locator
• Subjective (a.k.a. "illusory") Contours