James Randi on Assumptions:
More from James Randi:
Turning away from the light-hearted presentation of gory magic, we must not ignore the most notable purveyor of "horror magic," the Peruvian magician, Richiardi. He took audience discomfort to a new level by rarely providing any closure on the gruesome acts he performed. The audience was often left wondering about the reality of what they had just witnessed. Here is his contribution to the sawing illusion, with commentary by Teller.
Another great Richiardi video can be found here, in a clip from his TV show, "Chamber of Horrors." Finally, Penn & Teller rarely shy away from gore in their magic. Here is their homage to Richiardi.
The discovery in the early 90s of mirror neurons in macaques, neurons that fired both when the monkeys were performing a specific goal-directed hand action and when they viewed another monkey performing the same action, spurred a great deal of research and theorizing in the psychology and neuroscience communities. Unfortunately, many of the theories derived from the discovery of mirror neurons stepped away from the original empirical findings of Di Pellegrino et al. (1992), presuming at the outset (sans evidence) that mirror neurons in humans have evolved dramatically from those found in monkeys. That said, theorists have suggested (among other things) that mirror neurons are the source of human empathy, the evolutionary precursor to language (via action understanding), and that a mirror neuron deficiency is the cause of autism. These theories are all well and good...except that they all assume mirror neurons have behavioral consequences beyond those seen in monkeys, and they assume that humans have large circuits of mirror neurons (which have never been found in the human brain). Hickok (2009) provides one of the most well-constructed critiques of the limitations and exaggerations inherent to theories of action understanding through mirror neuron activity.
Germane to my field of study is the proposition that mirror neurons form the foundation for language (and serve an important role in the understanding of speech, providing the neural basis for the motor theory of speech perception, previously discussed here). It has been suggested that the earliest forms of communication were likely to be gestural (Arbib, 2002; Corballis, 2003; Fogassi & Ferrari, 2007). Arbib (2002) outlined seven theoretical stages in the evolution of linguistic capabilities. The first four stages involve adaptations in the ability to grasp objects with the hand and understand the grasping behaviors of other animals. Each of these evolutionary steps entails a further development of the Broca’s area homolog, including the development of mirror systems, yielding the ability to interpret the actions of others through simulation. As Arbib explained, “The evolution of mirror neurons extended ‘knowing’ from the individual to the social,” (pp. 14). Further imitative abilities allowed for a rudimentary manual communication system. As Corballis (2003) pointed out, modern wild chimpanzees exhibit a variety of manual gestures. He posited that they are one evolutionary component away from the ability to communicate effectively through mime: bipedalism. Indeed, it is likely that the earliest bipedal hominids communicated through pantomime, and this communication was accompanied by facial expressions and simple vocalizations that provided emotional valance (Fogassi & Ferrari, 2007).
A paper in press at Brain & Language (which I've made available here) examines one of the core premises of the Arbib theory of language evolution. If mirror neurons are at the heart of communication (allowing language recognition through simulation), and if language evolved from gesture, then a language that is overtly gestural, such as sign language, should be largely reliant on mirror neurons and mirror networks in the brain. Knapp and Corina (in press) evaluated three predictions derived from the mirror neuron theory of language, primarily through an examination of research in sign language:
- "Damage to the human mirror neuron system should non-selectively disrupt both sign language and non-linguistic action processing."
- "Within the domain of sign language, a given mirror neuron locus should mediate both perception and production."
- "The action-based tuning curves of individual mirror neurons should support the highly circumscribed set of motions that form the ‘‘vocabulary of action” for signed languages."
As I see it, this paper is something of a nail-in-the-coffin for the mirror neuron theory of language understanding. A language that should be most in-touch with the theoretical origin of spoken language, sign language, does not appear to be moderated by mirror neurons or mirror networks in the brain. Do we need to continue this fiasco?
Arbib, M. (2002). The mirror system, imitation, and the evolution of language. In C. Nhaniv & K. Dautenhahn (Eds.), Imitation in Animals and Artifacts. The MIT Press.
Corballis, M. C. (2003). From mouth to hand: Gesture, speech, and the evolution of right-handedness. Behavioral and Brain Sciences, 26, 199-260.
Di Pellegrino, G., Fadiga, L., Fogassi, L., Gallese, V., & Rizzolatti, G. (1992). Understanding motor events: A neurophysiological study. Experimental Brain Research, 91, 176-180.
Fogassi, L. & Ferrari, P. F. (2007). Mirror neurons and the evolution of embodied language. Current Directions in Psychological Science, 16, 136-141.
Hickok, G. (2009). Eight problems for the mirror neuron theory of action understanding in monkeys and humans. Journal of Cognitive Neuroscience, 21, 1229-1243. (link)
Knapp, H. P. & Corina, D. P. (in press). A human mirror neuron system for language: Perspectives from signed languages of the deaf. Brain & Language. (link)
My master's thesis defense is scheduled for next Monday. That said, I'm taking this week off from blogging, returning next week with renewed vigor. Thank you for your kind attention.
Throughout the past decade Soma has developed a unique way of entertainment, which took him all around the world. His original phone-act, acclaimed by his peers as "magic as unique, and as original as it gets", appeared in gala-shows and magic conventions all around Europe, the United States and Asia. He has won many prizes in many countries.
The main objective of Soma's magic is to deliver an experience never seen before. A professional way of entertainment: That is the purest expression of what he does.
Here is the act with which Soma won the FISM 2009 Grand Prix for Stage Magic:
Shawn Farquhar has been entertaining audiences around the globe for over two decades. His magic has been seen on Television shows like the X-Files and Highlander, in Motion Pictures like Spooky House and the Fly II, for corporate clients like IBM and Konica, and on the most luxurious cruise vessels such as Norwegian Star and Radiance of the Seas.
The Canadian Association of Magicians awarded Shawn the MAGICIAN OF THE YEAR, the Pacific Coast Association of Magicians awarded him the GRAND PRIX D'HONNEUR and the International Brotherhood of Magicians awarded him both STAGE MAGICIAN and SLEIGHT OF HAND MAGICIAN OF THE YEAR, making him the ONLY magician in history to win BOTH world championships!
Here's a portion of the act Shawn competed with :
Update: Word on the street is that Shawn has made it to the finals of the Grand Prix contest.
3 volunteers are brought onstage and requested to selected a dynamite looking firecracker. 4 are real and one is a dud ( he lights one to prove it - literally shaking the CNCC convention centre to its core with an enormous bang ) The volunteers each take one - the last spectator inadvertently providing the magician with incorrect information as to what number he has selected. With the magician now reaching for one of the remaining sticks ( using incorrect information as to what sticks remain ) - he places it in his mouth and begins to light it. Some members of the audience are horrified - not knowing whether to intervene to prevent a ghastly accident. A scream is heard and the magician's face is covered in blood ... he had planned it all and knew exactly which one to choose.
I can't help but be reminded of this often-fumbled magic trick (not for the squeamish), except that, in Doumergue's case, the failure was staged. No video is available of Doumergue's fire-cracker trick, but here's his well-known version of the torn and restored card.
In this performance Julius Frack is manically dancing around his attic in an eccentric tail-coat, magically designing an exquisite dress for his mannequin. His thimbles move to the rhythm of the music and his scissors mysteriously float shaping his vision. With this act he won several awards in international contests and a high reputation in the world of magic. In 2005 the young magic pro’s new full-evening show “Imagi©nations” started on a tour around theatres in Germany.
This year, he is competing in the "stage illusion" category, leading me to believe that he will probably be presenting a different act. His unique suspension illusion (seen below) could do him well in this category!
Since 1997, Jeremy has made several milestones for himself. He won several local and international awards for his performances. Jeremy is the First and Only Magician in Singapore’s history to win the Singapore Association of Magicians “Magician of the Year” Award for 3 consecutive years! He made appearances on local and foreign television broadcasts, newspapers and magazines. He was also invited as special guest speaker, lecturer and consultant in Singapore and overseas.
Here is a portion of his act featuring a re-thinking of the "Professor's Nightmare" rope trick.
source: the Taipei Times
Uh oh. It looks as if things have taken a turn for the worst at the FISM competitions in Beijing. From Tim Ellis at MagicUnlimited:
There was one incident that was so unexpected it left the room literally in shock.
After a contestant did an act featuring a travel theme where he gave a list of the countries he wanted to visit (which included Taiwan) a Chinese registrant leapt up from the audience, raced back stage and literally dragged the contestant back on demanding that he apologise because “Taiwan is not a country!!!”
Some of the other Chinese in the audience (including some of the cameramen) cheered, but the rest of the room sat with jaws gaping... and in one moment the beautiful veil of happiness FISM Beijing had woven over the last few days was ripped aside.
The competitions of the Federation Internationale des Societes Magiques begin in Beijing on Sunday. This is the most high-profile magic competition in the world, with past winners including people like Johnny Ace Palmer, Daryl, and of course Lance Burton. In lieu of shelling out the cash for a trip to China, next week I'll be profiling some of this year's competitors here, including video of the acts they're likely to be competing with. I hope you'll join me for my stay-at-home FISM 2009.
Update: Tim Ellis, a FISM jury member, is doing a FISM play-by-play over at his blog, Magic Unlimited. I've added his blog to the sidebar.
Photograph collectors in Maryland have discovered what appears to be the only known photograph of Phineas Gage. Gage is a legend in neuroscience and psychology. Here's why (from the Boston Daily Courier, September 20th, 1848):
Horrible Accident. Phineas P. Gage, a foreman on the Rutland Railroad at Cavendish, Vt., was preparing for a blast on Wednesday last, when the powder exploded, carrying through his head an iron instrument, an inch and a fourth in circumference, and three feet and eight inches in length. The iron entered on the side of his face, shattering the upper jaw, and passing back of the left eye, and out the top of his head. Singularly enough, he was alive at two o'clock the next afternoon, in full possession of his reason, and free from pain (Macmillan, 1986, p. 77).
In many ways, the story of Phineas Gage has grown into a myth, and the legend surrounding Gage's condition probably began with the newspaper article above. There is still a pervasive view that Gage recovered fully from his injuries in a very short period of time. While it was amazing that Gage survived having a tamping iron travel through his brain, by no means was he ever the same person following the accident. For more information on Phineas Gage, I suggest you track down two great articles penned by Malcolm Macmillan at the University of Melbourne:
- Macmillan, M. B. (1986). A wonderful journey through skull and brains: The travels of Mr. Gage's tamping iron. Brain and Cognition, 5, 67-107.
- Macmillan, M. (2008). Phineas Gage - Unravelling the myth. The Psychologist, 21, 828-831. (link)
h|t BPS Research Digest
Although something is obviously not quite right about the image, it doesn't look terribly out of the ordinary. It's difficult to pinpoint the abnormality until the image is rotated right-side up.
Right-side up, the image is grotesque. You can now readily notice that although the relative configuration of the eyes and mouth has been maintained, each element has been flipped upside-down. The illusion suggests that we are relatively insensitive to the specific features of a face during recognition (otherwise, the upside-down face would look abnormal). Instead, we rely on the overall configuration of said features. Here's an even more compelling demonstration of the effect using the faces of celebrities (and a little bit of creepy music):
Adachi, Chou, and Hampton (2009) created "Thatcherized" images of rhesus monkey faces.
The researchers presented their monkey subjects with un-Thatcherized images of normal and rotated monkey faces over and over, habituating the monkeys to the images. They then presented a series of Thatcherized images, reasoning that if monkeys perceived abnormalities in the images, they should become dishabituated, spending more time gazing at the new photographs. Just as predicted, only the upright Thatcherized images captured extra attention, replicating the Thatcher effect seen in humans, and suggesting that monkeys use face recognition strategies similar to those used by humans.
Adachi, I., Chou, D. P., & Hampton, R. R. (2009). Thatcher effect in monkeys demonstrates conservation of face perception across primates. Current Biology, 19, 1-4.
Thompson, P. (1980). Margaret Thatcher: A new illusion. Perception, 9, 483-484. (link)
In 1977, at age 30, William H. "Doc" Eason took a 2 week motorcycle vacation from his home in California and journeyed to Snowmass, Colorado to visit some old fraternity brothers. These friends co-owned the Tower Restaurant with John Denver. As fate would have it, one of the first people he met in Snowmass was legendary bar magician, Bob Sheets. This chance meeting changed the course of Doc’s life forever. The two week vacation turned into an incredible run of over 27 years. He never returned to California and to make a long story very short, Doc had Bob’s old job as the magic bartender and featured entertainer at John Denver’s World Famous Tower Comedy Magic Bar and Restaurant until it closed its doors on April 10, 2004.
Below is one of my favorite Doc Eason bits. This was the only video I could find of the entire routine. Although the video is less-than-perfect, it's the story that makes the trick.
Today, I was interviewed by Phoenix's KTVK Channel 3 for a segment they're preparing on psychology/neuroscience and magic, specifically focusing on the work that Steve Macknik and Susana Martinez-Conde are doing at the Barrow Neurological Institute. I've done magic on TV a few times before, and each time I'm struck by how limiting the camera is. After capturing some of the first film footage of a performing magician, psychologist Alfred Binet noted that the magic was not nearly as effective on film. Why might this be?
Magic is an inherently social enterprise, with each trick being a shared experience of something wondrous between the magician and the spectators. The most effective elements of misdirection build upon social norms. For example, if you want to divert attention away from your hands at an integral moment, there's no better way than asking someone a question or simply saying their name. Social norms dictate that we are to look a person in the eyes while answering a question. Not only is this person's attention diverted, but the rest of the audience typically shifts their attention to the person answering the question. The camera does not allow for this kind of social interaction between magician and viewer.
The other weapon in the magician's misdirection arsenal is joint attention. The magician's focus of attention suggests to the audience where their attention should be placed. You've probably had the experience of being compelled to follow the gaze of another person. In many instances it's exceedingly difficult to resist. Tomasello, Hare, Lehmann, and Call (2007) argued that we evolved the whites of our eyes for the purpose of facilitating joint attention. In fact, our closest relatives in the animal world, the African great apes, do not have enlarged sclera, and consequently aren't as sensitive to others' shifts in attention as even young human infants are. In most cases, television drastically weakens the effect of joint attention, nullifying its ability to misdirect.
In their 2005 Perception paper, Kuhn and Land presented the results of an experiment employing the following magic trick, performed live.
When performed live, only 20% of participants noticed the magician drop the cigarette in his lap on the first viewing. Kuhn, Tatler, Findlay, and Cole (2008) repeated the experiment, this time with participants watching a video of the magic trick. In this instance, the percentage of participants who noticed the drop increased to nearly 57%. In theory, the only difference between the experiments was the ability for the magician to interact and make eye contact with the spectator.
Unfortunately, much of my magic employs misdirection of this kind. I have a difficult time thinking of any piece from my repertoire that doesn't contain an element of social misdirection. Despite these limitations, I was able to pull together a few magical effects from my act that highlight some of the psychological tendencies that magicians prey upon. Once I know when the segment is going to air, I'll post more information here.
Kuhn, G. & Tatler, B. W. (2005). Magic and fixation: Now you don't see it, now you do. Perception, 34, 1155-1161.
Kuhn, G., Tatler, B. W., Findlay, J. M., & Cole, G. G. (2008). Misdirection in magic: Implications for the relationship between eye gaze and attention. Visual Cognition, 16, 391-405.
Tomasello, M., Hare, B., Lehmann, H., & Call, J. (2007). Reliance on head versus eyes in the gaze following of great apes and human infants: The cooperative eye hypothesis. Journal of Human Evolution, 52, 314-320.
Most magic tricks rely on the fact that people have built up a lifetime of experiences, drastically biasing the way they interact with the world. Magicians want you to make assumptions about what you're watching, as it distracts you from the true method. Once you have realized that your assumptions are false, it's too late for you to go back. Watch how I lead you down a garden path and then pull the rug out from under you. There. How was that?
The most recent issue of Nature contains a short article about a workshop that happened last month in Lima, Peru, hosted by Medialab Prado. "Interactivos? Lima '09" brought together engineers and artists with the hope of generating new illusions based on the most modern technologies, and the finished products did not disappoint. The installations produced during the meeting included a magic wand that could change the shape of a person's shadow, a box that transformed a person's arm into the leg of a lion, and a telekinetic spoon that was moved by a hidden theremin (fast-forward to the 3:50 mark in the following video to see a demo of the spoon in action).
This conference was appropriate, as magicians have always been among the first to learn about and exploit new technologies. Famously, Robert-Houdin, the oft-labeled "father of modern magic," used electromagnetism even before scientists had developed applications for it. He used it in an illusion called the "Light and Heavy Chest." From magicexhibit.org:
He invited a spectator on stage to lift the small wooden box he said he kept to store his money. His volunteer always did this easily. Then the magician commanded the box to stay where it was, so it could not be stolen. No matter how hard the volunteer tried after that, he couldn't move it.
Hidden inside the wooden chest was a metal plate, and an electromagnet sat under the stage. When his assistant turned on the magnet, the strong attraction made it impossible to move the chest. Robert-Houdin wrote in his autobiography that at this time "the phenomena of electromagnetism were wholly unknown to the general public. I took very good care not to enlighten my audience as to this marvel of science."
It's even rumored that Robert-Houdin used this effect to prevent a war in Algeria.
The other act is a man named Charlie Caper. Here he is doing some equally creative (and arguably, more original) magic:
I think I'm rooting for the second guy...His climax is a change-blindness trick (the bowtie vanishes long before you realize that it's gone)!
Over at NewScientist.com, Richard Wiseman has published the results of his recent Twitter experiment on remote viewing (previously blogged about here). Wiseman traveled to a number of different secret locations. Once there, he directed Twitter participants to "tweet" about any feelings they were receiving about the secret location. Later, he sent them a link to a website that presented participants with images of five different places. They had to choose the location they believed Wiseman to be at. In addition, Wiseman probed participants about their belief in the paranormal and psychic ability.
Not surprisingly, the group (of nearly 1000) failed miserably. Wiseman treated the most frequently selected location as the group's choice in each of four trials. The group failed to choose the correct location on every trial. In addition, those who proclaimed belief in psychic ability performed no better on the task than those who professed no belief. Granted, this is far from being an ideal experimental design, as anyone with genuine psychic ability would get washed away by all the guessing within the group. What this study does accomplish is a demonstration of a possible (and promising) use for social networking sites by the scientific community.
Some folks are getting all bent out of shape about this experiment. I suggest you head over to the comments section on NewScientist.com and enjoy the circus.
A few weeks ago, I invited you to take part in an online survey for which I provided very little background. Your job was to determine which of two English words was the appropriate translation of a Japanese word. Since most people in the Western world have very little knowledge of the Japanese language (aside from "konnichiwa" and "sayonara") you were probably just guessing. But, is there anything systematic about people's guessing in an experiment like this?
What you didn't know while taking the quiz was that the appropriate translation was not always provided as one of the answers. Sometimes the Japanese word was paired with its actual translation and an unrelated item. Other times, it was paired with the opposite of its actual translation and an unrelated item (so, the Japanese word for "bright" was paired with "dark"). A recent experiment in press at the journal Cognition used a similar design. Nygaard, Cook, and Namy (in press) taught English-speaking participants the translations of a series of Japanese words that were presented auditorily, but unbeknownst to the participants, they were either learning the direct translation of the word, it's antonym, or an unrelated translation.
Nygaard et al. found that participants learned the items more efficiently (evidenced by accuracy and response time in a recognition task) if they were learning the true meaning or its antonym than if they were learning an unrelated translation.
from Nygaard et al. (in press)
Languages are thought to be abstract and arbitrary, with no systematicity between word sounds and word meanings (aside from onomatopoetic words). The authors argue that this experiment suggests a different story, that there is some sort of underlying sound to meaning correspondence that is systematic across language systems, as none of the participants in this study had even a rudimentary knowledge of Japanese. The antonyms were thought to benefit learning since they were from the same semantic category as the paired Japanese item.
I find this conclusion highly suspect. The authors point out a possible confound that I think is at the heart of the effect being seen here. During the learning phase of the experiment, the Japanese tokens were presented auditorily, paired with a written English translation on the computer screen. The spoken Japanese items were, of course, provided by a native Japanese speaker, meaning that the speaker knew the actual meanings of the words they were saying. Spoken language is a much richer source of information than the printed word. From a speaker's voice, we can ascertain things like their gender and age as well as gain information that can aid in the understanding of the words they're saying. In fact, the authors cite research demonstrating that listeners can intuit word meanings based only on voice inflections (or prosody).
In the "Japanese Words Quiz," I wanted to determine whether people could guess the meanings of the Japanese words without any sort of auditory input. Granted, this is a much different experiment from Nygaard et al. and I didn't have a fully-counterbalanced design, but if there is any systematic phonetic (or orthographic) to semantic relationship that readers can pick up on across languages, then it would be quite possible that they could guess the meanings above chance levels.
I had planned to carry out a full statistical analysis of this data, but looking at the raw numbers tells me that further analysis is not necessary. The results were almost perfectly at chance, with an overall accuracy of 51%. Accuracy on matched trials (where the actual translation was one of the possible choices) was 52%, and accuracy on antonym trials was 50% exactly. That's not a promising outcome.
I'm thinking of following up on this experiment with a formal replication using spoken word tokens generated by someone who doesn't speak Japanese but who has training in Japanese pronunciation...Someone like a vocal performance major. Thus, they would be unequipped to provide prosody that would be informative to the true meaning of the word. Could be fun! Stay tuned.
Nygaard, L. C., Cook, A. E., & Namy, L. L. (in press). Sound to meaning correspondences facilitate word learning. Cognition. (link)
What are you planning to do this weekend? That's right...nothing. You have no plans (other than just sitting at home hoping that I'll post a weekend blog entry, which just doesn't happen, folks). So, let me give you a plan for the weekend.
Saturday evening, I'll be opening for Robert Mac at Phoenix's "Clean Stand-Up Comedy Showcase." There. You've got all the makins' for a wonderful evening: magic, comedy, and ... comedy. Best of all, it'll only cost you $5. Here's all the information you need in order to plan the night of your life:
What: Clean Stand-Up Comedy Showcase
When: Saturday, June 6th, 7:00PM
Where: Mountain View Rec. Center, 2927 East Campbell Ave., Phoenix, AZ (map)
Why: Seriously? You're asking why?
If you want to see all of this information repeated, please feel free to visit my facebook page for the event here. Here's a video of Robert Mac's stand-up to whet your whistle.
The experiment will examine the possible existence of ‘remote viewing’ – the alleged ability to psychically identify a distant location.
So, how is the experiment going to work?
Well, at 3pm (UK time) each day, I will travel to a randomly selected location. Once there, I will send a Tweet, asking everyone to Tweet about their thoughts concerning the nature of the location. Thirty minutes later, I will send another Tweet linking to a website that will allow everyone to view photographs of five locations (the actual location and four decoys), think about the thoughts and images that came to them in the thirty minutes before, and vote on which of the five they believe to be the actual target location.
If the majority of people select the correct target then the trial will count as a hit, otherwise it will count as a miss. There will be trials at 3pm on Tuesday, Wednesday, Thursday and Friday this week. Three or more hits in four trials will be seen as supporting the existence of extrasensory perception.
In addition to these formal trials, there will be an informal trial (to test the procedure) today at 3pm.
As well as being the first ever scientific experiment on Twitter, I think this is going to be the largest ever test of Remote Viewing, so I am excited about the project.
So, head on over to Richard's Twitter stream at https://twitter.com/RichardWiseman to take part in the fun!
Mahka Tendo is best known for his ground-breaking work with jumbo card productions which earned him a Silver Medal in Manipulation at FISM 1985. More recently he's brought out a selection of products including canes, with SEO Magic, and he was presenting a weekly magic spot on NHKTV in Japan.
The study outlined in the Scientific American article examined the motor contributions to speech perception in a different way. If we are constantly simulating oral gestures when listening to speech, then manipulating our own oral motor activity during speech processing should influence perception. Ito, Tiede, and Ostry (2009) presented people with an ambiguous word (somewhere in between "head" and "had") while a machine, pictured below, stretched the participants' mouths in one of three directions.
From Ito, Tiede, and Ostry (2009)
Two of the stretching directions corresponded to the way the face changes during the pronunciation of "head" and "had." The third was unrelated. As the motor theory would predict, the direction of stretching biased participants toward hearing the word that matched the facial movement, even if the token was more similar to the opposing word. The unrelated stretching condition had no discernible effect on perception. So, there's plenty of evidence that supports a motor component to speech recognition, but, as yet, no one has come up with an experimental design that can unequivocally refute motor theory (although methods in brain imagining are beginning to come close). It seems that it's largely unfalsifiable, which makes it a difficult theory to accept wholeheartedly.
P.S. If you liked the McGurk effect, you should check out this version of it combined with the Margaret Thatcher illusion.
Ito, T., Tiede, M., & Ostry, D. J. (2009). Somatosensory function in speech perception. Proceedings of the National Academy of Sciences, 106, 1245-1248. (link)
Liberman, A. M. & Mattingly, I. G. (1985). The motor theory of speech perception revised. Cognition, 21, 1-36. (link)
MacDonald, J. & McGurk, H. (1978). Visual influences on speech perception processes. Perception & Psychophysics, 24, 253-257.
For more information on the history of the bullet catch, I encourage you to read Jim Steinmeyer's treatise on Chung Ling Soo, The Glorious Deception.
The Japanese Words Quiz
In my blog entry regarding "The Fallacy of Personal Validation," I hit on the topic of probability estimation. People are exceptionally bad at accounting for population base rates when making decisions and are wholly incapable of recognizing randomness when they see it. In the example of an astrological reading, people underestimate the prevalence of certain personality traits in the population, thus personalizing what is in reality a quite generic personality profile. A new study just published in the journal Applied Cognitive Psychology by Paul Rogers and colleagues suggests that this gross inability to consider probabilities may be the factor that differentiates a believer in the paranormal from a nonbeliever.
Rogers, Davis, and Fisk (2009) examined individual differences in susceptibility to the conjunction fallacy, wherein people judge a series of random events as more likely to co-occur than to occur individually. Here's a concrete example. Rogers et al. presented people with the following situation:
Billy has a long lost friend who he has not seen in years. They were good friends in school but drifted apart when they went away to different colleges. Billy comes home from work one evening and sits down to eat his dinner.They then had participants rate the probability (chance in 100) of three statements:
- a. "Billy thinks about his long lost friend."
- b. "Billy's long lost friend unexpectedly phones him."
- c. "Billy thinks about his long lost friend and suddenly his long lost friend unexpectedly phones him."
The conjunction fallacy occurs when the third item (the conjunction) is rated as more probable than either event individually (the constituents). Statistically, the conjunction should never be more probable than each constituent. Interestingly, paranormal believers (as measured by the Australian Sheep-Goat Scale) were significantly more likely than non-believers to give the conjunction a higher probability rating. Although participants who had more experience in math, statistics, and psychology made fewer conjunction fallacy errors, the effect of paranormal belief was still present when math ability was held constant.
As Cohen (1960) stated, "Nothing is so alien to the human mind as the idea of randomness."
Cohen, J. (1960). Chance, skill, and luck: The psychology of guessing and gambling. Baltimore, MD: Penguin Books.
Rogers, P., Davis, T., & Fisk, J. (2009). Paranormal belief and susceptibility to the conjunction fallacy. Applied Cognitive Psychology, 23, 524-542. (link)
The spinning of the curveball creates both a physical effect (“the curve”) and a perceptual puzzle. The curve arises because the ball’s rotation creates an imbalance of forces on different sides of the ball, which leads to a substantial deflection in the path of the ball. The perceptual puzzle arises because the deflection of the ball should appear gradual, but from the point of view of the batter standing near home plate, the flight of the ball often appears to undergo a dramatic and nearly discontinuous shift in position (this sudden shift is referred to as the curveball’s “break”).
As I can't post any of the illusions themselves on this blog, here's a related video of 10 classic optical illusions in 2 minutes.