FINAL BLOG ENTRY

The most surprising thing I learned this semester was about taste buds.  Like many people who have not learned in depth about perception, I believed that each taste bud was for a different flavor, and I also had the misconception that different flavors had different locations on the tongue (taste bud map).  Perhaps the funniest thing I previously thought was that I could eat a Warhead (very sour candy) and not feel the pain by placing it farther back in my mouth so as to avoid my sour taste bud receptors.  My favorite fact I learned was that your taste buds are not just located on your tongue, but also on the roof of your mouth and in your throat.  Also, that taste buds on the tongue are especially present on the front tip, the sides, and the back, but not so prominent in the middle.  I also enjoyed learning about taste modification and illusions, because I had always been curious as to why orange juice tasted so foul after I brushed my teeth.  Supertasters, non-tasters, and regular tasters were interesting to study because I wondered as a child why some people were able to handle spicy foods and why it affected some people so much more.  Overall, taste was my favorite topic of study because I learned so many new things and destroyed so many misconceptions.

The aperture problem

The aperture problem is that neurons are only sensitive to a small visual field, an aperture.  So motion in this aperture can be ambiguous when it comes to one-dimensional lines.  It may appear that the lines are moving left to right, but they could be moving diagonally to the right.  It is hard to tell because you cannot see the ends of the line, only the small visual field that the neuron is responsible for.  To make up for this problem, the neurons all have to work together and combine their signals to determine the correct direction of motion.  In combining, the neurons can compare signals from each visual field to determine which direction is the right one because they have the overall picture as opposed to a small little portion.  When researching this problem, I found an interesting site which had an example of this with a series of black and white diagonal lines in a small circle moving what appeared to be diagonally.  But the site pointed out that the movement could be vertical as well, and once I read this and examined the movement again, I was surprised to see how this worked out.  I think it is interesting how much I rely on my perception, specifically my visual system, and how much I trust it despite the fact that it can deceive me so easily.

Synesthesia

Synesthesia is a phenomenon where a stimulus evokes a bizarre response.  In color synesthesia, a particular word or letter is associated with a certain color, and appears to be printed in that color.  This is the most well-known type, but there are also types where dates bring out different personalities, or numbers cause a strange reaction.  The stimulus can be visual, auditory, or completely unrelated to the senses.  It is thought to be hereditary as it tends to run in families.  I find color synesthesia to be the most interesting, probably because it is thought to be the most common and therefore the most researched.  What I love about it is that when synesthetes are tested on their associations, months, even years later they will still recount the same exact associations.  A non-synesthete who is tested on a similar task can only recount associations with 20-40% accuracy.  Not only does synthestia have a genetic cause, but it can also be caused by drugs, surgeries, and other external sources.  People with genetically caused synesthesia also tend to have higher IQ’s and are more creative than non-synesthetes.  When I encountered a list of famous people, past and present who have synesthesia, I was not surprised to notice that the majority of them had careers requiring creativity: artists, composers, and music producers.  I even found out that Pharell Williams, I musician who I enjoyed listening to in high school, was a synesthete.  I think that going through life with these effects would be extremely interesting and not really a hindrance as many people view it.

Faces

I was interested in researching facial expressions because I actually had trouble deciphering emotions in the faces in the text book.  The book said that we can accurately judge six emotions across all cultures: happiness, sadness, disgust, fear, anger, and surprise.  Only by process of elimination could I label each emotion, and I’m not sure if I was even correct in this.  I took a test online where an emotionless face was displayed on the screen and the same face with one of the emotions flashed quickly and it returned to a blank face.  You then had to select which of the six emotions it was.  I had to replay the emotion multiple times, and even doing this I only answered seven of the ten right on the first guess.  I feel that in real life I can usually judge how a person is feeling based on their facial expression, but judging a complete stranger’s expression in a photograph does not reflect this.  I am curious to know if there has ever been a test of facial expression recognition comparing emotion recognition in photographs and real people.  I wonder if people would be able to successfully label emotions more with live people than photographs.

Distraction and strange visual things

When we are not paying attention, we can fail to notice very strange things in our visual field.  I remember in my intro to psychology class, we watched the video of the boys and girls passing a basketball, and we were told to count the number of passes.  Because I was distracted, I failed to notice a person in a gorilla suit walk across the screen.  My attention had been captured by another task.  Many movies have mistakes which many people do not notice, but if you watch closely enough, you can see them.  I remember the first time I noticed a mistake like this as a child, when I was watching Liar, Liar with Jim Carrey.  While sitting in a car, at one point his son has his seat belt on, then they come back and his seat belt is not on, and when they show him again its back on.   Also, in Fatal Attraction, while Glenn Close is lying in her bed, her sheets switch from on her, to off her, to back on.  However, I usually don’t notice small mistakes like this because my attention is usually on the movie in general.  It is only when I am bored and start scanning for other things to watch that I notice these mistakes.  Another instance when I fail to notice mistakes because my attention is on something else is when I read.  If I am re-reading a paper or reading a magazine and there is some error, my mind is distracted with the reading that I do not even notice and just mentally fix it.

Color blindness

When thinking of what to write about this week for my blog, my mind wandered back to childhood.  As a kid, I always wondered if everyone saw the same colors, or if we thought we were seeing the same colors but actually what I see as pink someone else sees green.  Then we both are told that the color we see is pink, so we think we are seeing the same thing.  Along these lines, I decided to read about color blindness, when a person cannot tell a difference between two colors for my blog.  Almost always, color blindness is inherited as a recessive trait from the X chromosome (so it is more common in males), although it can be acquired.  It can be acquired through damage to any part of the optic pathway.  There are also different types of color blindness, based on the different types of cones in the eye.  A typical person has rods and cones, and there are three different types of cones.  Color blindness can result from having only one type of cone (complete color blindness, no distinction between colors), or two types of cones (partial, no distinction between certain colors).  It can also occur because one of the types of cones is sensitive to a shifted wave length, and thus different colors.  To test if a person is color blind, they are usually given the Ishihara color test, which is a circle full of dots, the background red and a number in the middle in green.  If a person just sees a circle full of dots and cannot discriminate the number, they are colorblind.  About 8% of men are colorblind, so it is a significant issue for which we are still trying to find a solution.

The Eye is at Once the Master and the Slave of Vision

In my opionion, when Roger Carpenter said that “the eye is at once the master and the slave of vision, he was referring the the design of actual eyeball.  Our vision is very sharp in the center of our visual field, but it is not as crisp on the peripheries.  This is because, around the fovea (light from the center our of visual field strikes here), we have more cones.  This area has the greatest acuity because cones work best in bright light conditions.  The periphery has more rods, which work best in low light conditions and thus the area is not as sharp.  So, because of the design of the eye, we are restricted and limited in our visual field.  At the same time, the eye is the master of vision (near the fovea where it has the greatest acuity), and the slave of vision (near the periphery where vision is not as crisp).

My Favorite Optical Illusion

As a child, I was never able to figure out the optical illusions on the backs of cereal boxes, and I still cannot.  I was never able to see the image that was supposed to pop out at you.  However, there are other optical illusions that I do like, and one of my favorites is the shape that looks like an E made from cylinders.  Doing some research, I found that optical illusions work because of similarity between structures, our brain continuing patterns, and connecting an object based on expectations.  On closer look at my favorite, you see that the bottom and middle cylinder do not work.  The middle connects on one side to the top of the shape and on the other to the bottom.  The bottom cylinder does not have any depth, it appears completely flat.  However, if you just look at the shape you do not notice these things, only when you examine it closely do you see the flaws.  I believe this is due to our expectations and our brain filling in missing pieces, but this is just speculation.

Blindness cuts me off from things…

Helen Keller once said, “blindness cuts me off from things; deafness cuts me off from people.”  I think what she meant by this was that not being able to see cuts her off from objects, while being deaf prevents her from communicating with people.  Not being able to hear means that she could not carry a normal conversation.  Although most deaf people can use sign language, Helen Keller could not because she was blind.  Therefore, she had no ways of communicating with people.  She could speak to people and they could listen, but she could not actual interact with them.  I could not imagine a life like this.  For my first blog entry, I wrote that the sense I coud not live without would be sight, but I cannot imagine not being able to communicate with people.  Although sign language would be an option, very few people actually know sign language.  Interacting with people is a huge part of my life, I love meeting new people and learning from the experiences they have had.  Without hearing, this would be a very difficult task and only possible with people who know sign language.  I cannot even begin to imagine how difficult a life like that would be.

The One Sense I Could Not Live Without

When considering this question, I went through every sense and thought about what it would be like to live without it.  My first thought was that I could absolutely live without taste.  Although I enjoy eating delicious foods, my life would not be difficult without it.  Next, I thought of smells.  Like taste, I enjoy smelling all kinds of different scents, but I feel that I could live without it if need be.  Touch, as well, is convenient, but not necessary.  The last two senses gave me the most challenging decision.  To give up sound would mean I couldn’t listen to music, which is a huge party of my life.  Also, although I could watch tv or use sign language to communicate, it would be hard to pick up on tone of voice, which can completely change the meaning of a statement.  However, I felt that sound was less important to me than sight.  Living without sight would be more devastating for me than losing any other sense.  Not only would life be extremely difficult, but I would also have to place all my trust in others.  It would be difficult to go anywhere or do anything, like everyday activities such as grocery shopping, watching movies, going to class, or anywhere I have to find my way.  Another dreadful thing would be not being able to sightsee or observe other cultures when traveling.  One of my favorite things to do when I travel is to see all the famous landmarks, and to take in the new culture I am unaccustomed to, which I would not be able to do any more.  Considering how life would be without each sense, I think that sight is definitely the one I could not live without.