Monday, June 25, 2018

Virtual reality technology opens new doors of (spatial) perception

Within the past few months, using immersive technology in the lab has enabled researchers to study sound perception in realistic settings! Virtual reality was used to probe auditory special awareness in real-life-like studies. The experiment has somebody put on headgear that puts them into a parklike setting. They are then told that they will hear a sound, and they should turn their head in the direction they hear it coming from. While doing this, the experimenter (Travis Moore, in this case) manipulates two essential location cues. The first one is the difference in timing from when the sound wave reaches the person's ear (measured in millionths of a second.) The other is the difference in sound pressure levels registering in each ear.
What they found was a considerable variability in how much weight subjects' brains assign to each cue. This is important since we don't yet know how the process of integrating two cues plays out in real-world listening tasks. Technologies like the ones used in this study should help yield better hearing aids for the hearing impaired, more accurate diagnosing of auditory disorders, and a richer sound experience in video games. Perhaps we can make acoustics of simulation indistinguishable from the real world! If something like this does happen, I'm wondering how different it would be to watch a movie and have it sound like it's happening in real life. I'm thinking that would be really cool!J

the ganzfeld experiment
the ganzfeld experiment is a technique used in parapsychology which is used to test individuals for extrasensory perception (ESP). The ganzfeld experiments are among the most recent in parapsychology for testing telepathy.
In a typical ganzfeld experiment, a "receiver" is placed in a room relaxing in a comfortable chair with halved ping-pong balls over the eyes, having a red light shone on them. The receiver also wears a set of headphones through which white or pink noise (static) is played. The receiver is in this state of mild sensory deprivation for half an hour. During this time, a "sender" observes a randomly chosen target and tries to mentally send this information to the receiver. The receiver speaks out loud during the thirty minutes, describing what he or she can see. This is recorded by the experimenter (who is blind to the target) either by recording onto tape or by taking notes, and is used to help the receiver during the judging procedure.
In the judging procedure, the receiver is taken out of the Ganzfeld state and given a set of possible targets, from which they select one which most resembled the images they witnessed. Most commonly there are three decoys along with the target, giving an expected rate of 25%, by chance, over several dozens of trials.[9]

Tactile Illusions

Image result for writing on chalkboard

    As we learned reading our text, See What I'm Saying, our brain's senses do not work independently as once thought. Our perceptual experiences are essentially multi-sensory. Because what you feel is strongly affected by what you hear, (cross-modal interaction), we can experience illusions with our sense of touch when paired with hearing. If you happen to have access to a chalkboard this is an interesting illusion to test out. Write your name on the chalkboard. Now write your name on the chalkboard while listening to music with headphones on. You should feel a difference in the chalkboard. Without hearing the sound of the chalk scraping against the board, it should feel smoother. This example of cross-modal interaction is most powerful between our sense of touch and hearing.

The Ganzfeld Effect

The Ganzfeld effect is a phenomenon of perception caused by exposure to unstructured stimuli. Unstructured stimuli in the form of white noise and or a uniform field of light can cause your brain to actually hallucinate. This effect is the result of the brain amplifying neural noise in order to look for the missing visual signals. The noise is interpreted in the higher visual cortex, and gives rise to these hallucinations. The video linked will provide more information about this phenomenon and you can see two people share their experience trying it out themselves.

Sunday, June 24, 2018

Why you think your phone is vibrating when it's not.

Are we hallucinating when we feel our phone "vibrate" and we look down and do not have any notifications? While it may not necessarily be an actual syndrome, this does happen regularly to a lot of people including myself. Sometimes I either think I felt my phone vibrate or I think I heard a ring. Some researchers and doctors argue we could be hallicinating because our brains are perceiving a sensation that is not actually present. This also has probably been a thing since landline phones were invented; however, it is more common now because people are always on their phone and we have the ability to take it every where we go. One article I read even states, "Individuals with phantom vibration syndrome are so accustomed to hearing their phone vibrate or ring, that their brain expects more." There are many other factors as to why this could be happening as well. There are many studies that show the reasons why and even more studies are still being conducted today.

Coke or Pepsi?

In the video, Buzz-feed does an experiment where the participants try and determine if they're drinking Coke or Pepsi. This experiment has been repeated over and over through out the years with different participants but it is interesting to see if people are able to determine the difference between the two. Most participants were able to tell the difference but most likely because they have drank a decent amount of both in their life time. Just like the book, See What I'm Saying, states, "we all have the ability to be expert taste testers." It's all about attention an practice. Therefore, someone like me who prefers coke over Pepsi will most likely be able to tell the difference between the two because I'm actually paying attention to what I am drinking. Where as someone who likes both, does not necessarily prefer one over the other, may not be able to tell the difference. This is because they most likely aren't concerned about which one the restaurant carries and just asks for "Coke or Pepsi, what ever you have." Nine times out of ten the waiter or waitress brings either over without telling you what it is and these people are the ones who aren't paying attention.

Saturday, June 23, 2018

Perception And The Art of Magic

Luke Dancy is a well-known magician who has been practicing magic for almost 30 years! In the video I attached, he talks about perception and says how the art of magic is making people perceive things in a way that will fool their minds. Luke says “The same thing can be said about life: Things are based on the way you look at it; there are two sides to every reality.” Living in Las Vegas, he says he sees it all the time - people tend to get fooled by the “friendly” environment there, but in reality, it’s usually just one big illusion. After a short talk, he goes right into a simple card trick (which you can watch on the video.) When the “act” is over, he shows the people watching how he did it and explains that it was just testing their perception. We all enjoy watching magic shows because they’re entertaining and exciting; however, what I find interesting is that the whole thrill we get from the performance is just somebody manipulating our brains to perceive things the way he or she wants us to. I always knew that magicians learned to do certain tricks, practiced them, and then performed, but I never thought about it in depth until now. What amazes me is how all it takes is one (experienced) human-being to stand up in front of a crowd, and literally fool every person’s mind and perception! Does that scare you at all? To me it seems just a little “creepy”, what do you think? 

Alice in Wonderland Syndrome

After reading Chapter 6 in the text, I couldn't help but think of Alice in Wonderland Syndrome. It's a rare condition that causes people to experience size distortion such as micropsia, macropsia, teleopsia, and pelopsia. In other words, it causes one to perceive objects and/or one's own body to either grow or shrink, just like Alice in Lewis Carroll's novel, for which the condition is named. This condition is not one of the eyes, but rather, one of perception. These episodes may also occur alongside migraines and epilepsy, but typically don't last long, resolving in under an hour.

As a child, I experienced this quite often, mostly at night when I would try to fall asleep. It was terrifying. Even with my eyes closed, I could see and feel everything shrinking and moving away from me, sort of like the endless hallway scene in Poltergeist, and I felt like I was growing in size. I would perceive my hands growing, my fingers extending in length so far that to bend them required the same amount of force as to twirl a long wooden rod. Using my mediocre 7-year-old vocabulary, I could not effectively communicate that I was hallucinating, so my parents took me to an eye doctor. They found nothing wrong with my eyes; I have 25/20 vision, but the doctor fitted me with bifocals anyway, because I described things as appearing "small" and "far away" during these episodes. As I aged, the episodes became less and less common, and now rarely happen at all, and only occur if I'm extremely sleep deprived. It wasn't until I was a senior in high school and came across an article about Alice in Wonderland Syndrome that I suspected what might have been going on when I was a kid.
Anyway, I just thought this is an interesting example of how perception can go awry. Below are a couple of websites that describe the condition in more detail.

Color Affects Perception of Taste

We taste what we see. I'm sure we all want to think we'd be smart enough to taste the difference between, say, lime and strawberry gummy bears. But if you've ever looked at the back of a bag of Haribo gummy bears, under the green gummy bear, you won't see "lime" or "green apple" listed as the flavor. Green Haribo gummy bears are actually strawberry flavored.

If you're anything like me, you'll question whether your entire existence is a lie. But as it turns out, this is a perfect example of how what we see - color - can influence what we taste. Generally, we perceive red foods as sweet, green foods as tart, yellow foods as sour, and so on. This is the reason food manufacturers put dyes in food to begin with. It enhances the food's perceived taste. Only, in this case, the color choice is rather deceptive.
This video shows this effect in action. So if you could have sworn green Haribo gummy bears tasted like lime or strawberry, don't feel so bad. You aren't alone. It turns out your brain is to blame for jumping the gun.

Visual Cliff Experiment

Is depth perception innate or is it learned through experience? The visual cliff experiment sought to answer this question. In the experiment, a table was designed so that a checkered pattern would appear to drop off like a cliff. Infants were placed on this table and coaxed to cross the "deep end" of the table by their mothers to determine whether or not these infants possessed depth perception. And as it turns out, they did. The original conclusion of these experiments was that depth perception was innate, although all these infants had unavoidably already had experience interacting with their environment.

Of course, these experiments took place before ethical concerns were more widely considered. Many of the infants would cry for their mother's help because they were too afraid to cross the "deep end". Regardless, depth perception is now considered to be partially innate, refined through experience.

How do you remember where you parked your car?

Neuroscientist Neil Burgess gives us a good understanding on how the hippocampal, the area responsible for memory, works to create a cognitive map for us to know where you we parked the car or if we going in the right direction.  My husband seems to have a good sense of direction and always does all the driving anytime we take a trip. I on the other hand don’t feel I am as good in finding my way.  
Neil Burgess points to studies with rats and mice that point to the finding that the brain neurons communicate with each other by sending little pulses or spikes of electricity marking a spot in the space the rats are in. Together these space cells form a map for the rest of the brain, informing where you are. Place cells activating each other via dense interconnections and then reactivating boundary cells to create the spatial structure of your surroundings and viewpoint.  Grid cells move this viewpoint through that space. Head direction cells, fire like a compass providing the viewing direction from which you generate an image for your visual imagery. This is an impressive mechanism that all works together to tell you where you parked your car.
The hippocampal continues to grow as place cells, grid cells, boundary cells, head-direction cells and visual imagery continue to develop its cognitive map.  This explains why my husband is better at direction then I am. He simply does more driving and his hippocampal is more developed. I tend to do less driving and in fact if I am going somewhere for the first time I would rather ask my husband to take me then to make the effort to learn how to get there. Well, based on this, I think I will try to do more of the driving and develop my hippocampal to get better at knowing my way around.

Below is the link for Neil Burgess Ted Talk: