Download Dazzled by the mystery of mentalism: The cognitive neuroscience of

Dazzled by the mystery of mentalism:
The cognitive neuroscience of mental athletes
Abstract: We review how often distortions on the cognitive mechanisms underlying the virtuosism
of mental athletes, including the frequent link to autistic savants or synesthesia, result from the
confusion, misconceptions and even lack of rigor found in scientific literature. We present specific
cases were ignorance about the basic training techniques of mental athlete’s world causes serious
interpretation and methodological problems. Calculations seem obviously more impressive if they
mysteriously pop-out in the air from unexplained virtues of an unexplained brain. The task of
cognitive neuroscience is the opposite. It is to find and reveal the trick and seek to unfold which
operations (often much more normal than they seem) result in these seemingly extraordinary
performances.
1. Extraordinary claims require extraordinary evidences
1.1.
Mental athletes in scientific literature
The achievements of Mental Athletes (MAs) are indeed impressive: the world record for memorizing
the order of the cards in a previously shuffled 52-cards deck is 27 seconds; three-digits by three
digits-numbers multiplications are made in less than 5 seconds, and the world record for
memorizing the pi number is 80 thousands digit, recalled in 48 hours and 35 minutes [1, 2]. The
mechanisms and algorithms used by MAs achieve these results are widely known and should be of
great value to cognitive neuroscience. However, a lot of popular myths still persist which influence
and confuse cognitive research. For instance, consider the case of a recent article [3] studying the
neural bases of calendrical skills, i.e. the ability to rapidly identify the weekday of a particular date,
in a mental calculator, Yusnier Viera (YV), concludes: “The fact that YV does not fall within the
autistic spectrum suggests that his skills are not supported by neurobiological peculiarities and
could be acquired by other people”. This conclusion is completely reasonable but somehow ignores
that calendrical calculations can be easily achieved by any person with a little practice. For an
informed person on MAs techniques, conclusions about the non-genetic determinism of calendrical
calculation would be as surprising as finding a manuscript in a physics journal, saying, for instance,
“We should conclude that Uri Geller did not bend spoons with the power of his mind”.
Here we review how often distortions on the cognitive mechanisms underlying the virtuosism of MA,
including the frequent link to autistic savants or synesthesia, result from the confusion,
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misconceptions and even lack of rigor. This work builds on previous efforts of Makoto Yamaguchi
who has pointed about the necessity of more rigorous research on savant-syndrome [4-8].
We argue that the main problem in this investigation is that mental athlete’s techniques have been
largely neglected. Instead, they should be at the center of the debate, since all MA recognize that
training procedures are necessary and sufficient to achieve high levels of performance [9, 10]. They
are sufficient since the vast majority of people with a certain amount of high quality training
procedure can reach high standards in all disciplines of MA. More importantly, they seem necessary
since there are no records in MA championships in which participants without classic training
procedures have reached master levels of performance. Some have claimed virtuoso performance
without training procedures. But this mainly begun as anecdotes which have been almost
impossible to demonstrate and in cases with sufficient scrutiny - as in the case of Daniel Tammet
which we discuss below - they have been debunked [10, 11].
A similar conclusion comes from the vast work of K Anders Ericsson in expertise [12]. After a
careful investigation of prodigies in chess and other cognitive domains, he came to the conclusion
that the total time of deliberate practice is by far the best predictor of performance. Ericsson has
carefully analyzed the trajectories of "chess geniuses" showing that 1) the young talents have many
more hours of training that people believe they have and 2) that without sufficient deliberate practice
they do not reach master levels of performance. Even if the anecdote that World Chess Champion
Jose Raul Capablanca learned chess just by seeing his father play is true (which is hard to
demonstrate) he would certainly not made it to world champion without many hours of methodical
training. Yet, in the scientific literature it is often argued that prodigious calculators come in two
classes: those who train and those who have a natural gift or talent (savants). We do not claim of
course that there may be broad variability in an individual's capacity for mental calculation. We
simply state that it is unlikely (or at least that there is no rigorous evidence) showing that the highest
levels of performance in mental calculation can be achieved without a training process based on
explicit procedures and algorithms.
We argue that scientists investigating prodigies should remain highly skeptical and avoid the
temptation of believing that these individuals are endowed with special natural gifts [13]. We present
specific cases were ignorance about the basic training techniques of mental athlete’s world causes
serious interpretation and methodological problems. Scientists, who should be skeptic by nature,
are often less skeptic than magicians themselves. Harry Houdini was the most emblematic of a very
influential tradition of skeptic magicians actively exposing esoterism, charlatans and fraudulent
artists. It is important to understand that the task is not easy since it requires inhibiting natural
psychological reactions. Woody Allen´s film "Magic in the Moonlight" brilliantly describes how even
the most rational and skeptical mind may be dazzled and confused by the mystery of mentalism.
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1.2.
The tricks and algorithms behind exceptional mental arithmetic
We begin with a concrete case of the analysis of a prodigy that performed exponentials of the form
xy with a basis (x) between 10 and 99 and exponents (y) between 10 and 20 [14]. But in fact the
prodigy only respond the third and four digiit of the correct response (in a forced choice between
four two digit numbers). In the paper, it is argued that this is done because the result of the
calucluation are number with high number of digits. To the eye of a trained magician this
immediately suggests a trick which may vastly simplify the calculation process. This task can
"simply" be achieved by memorizing a table containing 990 two-digit numbers, 90 possible basis
times 11 possible exponents. This task requires substantial effort and a few days of training for
experts, but it is certainly easier and very different in nature than performing the full exponential
calculus. The result of both processes is exactly the same in the subset of tasks used in this
experiment. In the paper this possibility is simply not taken into account. This is an example of what
we present as insufficient skeptical analysis of the performance of a prodigy.
It is of course not that difficult to discard this possibility. The prodigy could be asked different digits
in some trials. But none of this is reported in the paper and the possibility that the prodigy may be
using a shortcut (a trick) to achieve the task is not even considered. Moreover, it would have been
particularly desirable to have an introspective report by which the prodigy can explain and describe
his calculation procedure. Its particularly important because, contrary to other demonstrations of
MA, there are no reported algorithms to achieve exponentiations of large numbers [15, 16]. If an
accessible mental algorithm to calculate exponentials exists, it would have important practical
implications in numerical calculus. However, the details on the calculation process is extremely
succinct which makes it almost impossible to use it to make conclusions or inferences: “ Firstly, he
mentally calculates, retrieves rote memory, and, combines arithmetic information in working
memory, and thereafter, he constructs the output number at the very end of this complex procedure
in a sequential manner starting from the firs digit”.
If there were a specific detailed procedure, a signature of such algorithm could be found for
instance in the response time to different digits and to different numbers in the sequence. It is of
course possible that the prodigy was actually making the calculation. But as the data stands this is
impossible to tell. For all we know he could be performing a much easier task which a mental
athlete may achieve within a few training sessions. Our argument is that a more skeptical analysis
which inquires about the mechanisms used to achieve the task and which addresses possible
shortcuts and tricks is necessary to guide an informative cognitive neuroscience research of MA.
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In fact, the same prodigy (R Gamm) had been previously studied by a different research group [17].
The aim of this study was to investigate regular calculus in controls compared to the prodigy. As a
demonstration of the extraordinary calculations of R Gamm, it was shown that he can calculate the
sine of several numbers up to ten digit precision. This is yet another calculation for which there is no
known mental algorithm (Taylor approximation is used for trigonometric functions usually up to 3 or
4 digit precision [15]) and for which the current report remains obscure about the procedures by
which this was achieved.
We argue that using RTs variability to implicitly infer the algorithms used by MA combined with
explicit introspective reports is necessary for a rigorous cognitive neuroscience of prodigies. A
perfect example of such standard is the work on training of expertise by JJ Staszewski [9] where he
trained subjects for years until they reached the standard of masters of mental calculation. During
the training process he tracked the response time to each digit to understand how the task
architecture changed throughout the process of learning. A very simple example of a simplifying
algorithm which is known to all mental calculators is how to square a number. Using the formula
x2=(x-A)*(x+A) + A2 can make this operation much simpler by using the adequate value of A. For
instance, 23^2 is more easily calculated as 20*26 +9, using A=3. In this way, with just hours of
training a normal person can achieve standards of calculus which make him look like a virtuoso to a
naive observer. This algorithm has a signature which can be submitted to rigorous scrutinity; it is
expected that the response time to x2 should be a precise function of a (poner la forma e incluso
quizas la figura que dibujamos...). This makes it almost impossible for a MA to fake response times.
Often in performances MA slow their response to make it look hard (even when it is a relatively
simple memory retrieval). However, it seems almost impossible to simulate the precise dependence
of RT with a. [18].
1.3.
Danniel Tammet as a case study
Tammet attributes his calculation abilities to an epileptic attack at his infancy. He was featured in a
popular 2004 documentary called BrainMan and became since an extremely popular icon. The fact
that his prodigious mental abilities result from a very distinct cerebral condition, associated to
autism is often taken as granted both by the general public and also by scholars who have tracked
his case. However, over the last years, several skeptic analysts have raised very serious concerns
about his case [10, 11]. Here we refer to the main arguments and point the readers to the critical
literature for more in depth analysis.
First, as discussed by Foer in his book "Moon walking with Einstein" [11], Tammet´s mental
achievements are standard and within the range of what mental athletes achieve. The reason why
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he has become such a popular icon (as his precedent Rainman) is not so much for what he does,
but by how he claims he does it. The permanent references to savant, to synesthesia and to more
mysterious and non-laborious manners of achieving mental success make his case more appealing.
However, the evidence suggests that his achievements (which are extraordinary) may be more the
result of extensive deliberate practice than that of an exceptional mind.
The remarkable mathematical detective work of Ronald Doerfler deconstructing the documentary
BrainMan [10] and Joshua Foer in his best-selling book “Moonwalking with Einstein”, provide
excellent arguments to argue that Tammet is lying about his method. This should not be taken as a
personal attack or charged with any moral value. It is a scientific hypothesis that should always be
in consideration when studying calculating and memory prodigies, as when assessing paranormal
demonstrations like the ones performed by Uri Geller.
When Foer suggested that Tammet’s abilities may simply reflect intensive training using standard
memory techniques, rather than any abnormal neurological condition per se, psychologist
Alexandra Horowitz described Foer's speculation as among his book's few "missteps", questioning
whether it would matter if Tammet had used such strategies or not [19]. Here we argue that this is
precisely the most important consideration for cognitive neuroscience. Not focusing so much about
the achievements but instead on how they are achieved. The entire point of investigating prodigies
is to decipher the cognitive mechanisms by which they perform their feats. Not having the correct
cognitive model used to solve the task is certainly a serious mistake. Nevertheless, the faking
hypothesis has been largely ignored in many important scientific articles on mathematical prodigies.
One of the many examples investigated by Ronald Doerfler is that in one of his classic
demonstrations Tammet divides 13/97 [10]. This particular operation is famous to mental athletes
because dividing by 97 results in a repetition of shifted patterns of 96 digits and hence can be
relatively easily remembered. Moreover, the pattern can be divided in two complementary
segments, so just 48 digits should be stored in long term memory. 1/97 can be compactly written as
1/97 =
.010309278350515463917525773195876288659793814432
98969072164948453608244226804123711340206185567
.010309278350515463917525773195876288659793814432
98969072164948453608244226804123711340206185567
......
or more shortly as
1/97 = "0.ABABABABABAB..." where
5
A=010309278350515463917525773195876288659793814432
B=98969072164948453608244226804123711340206185567
.
This particular division has one notable feature. Adding A+B results in 999999..... i.e. all digits of A
and B add 9 More importantly, changing the numerator to any 2-digit number less than 97 simply
cycles the starting position of the repeating group to another location that can be easily determined
(see [10] for further details).
As we already discussed with the calculation x=(x-a)*(x+a)+a^2, tthis procedure to calculate 13/97
has signatures. Hence, the hypothesis that Tammet is using it to solve his task has predictions
which can be subject to experimental inquiry. It is expected that in the onset of each fragment the
calculator should slow down revealing the onset of the retrieval process. It is expected that the
recitation of digits should be faster within each segment (A or B) and be slower in the transitions
between these remembered chunks. This is exactly what happens when the velocity of recitation of
Tammet's calculation of 13/97 is measured. He slows down and even shows some verbal hesitation
in the transition between the chunks. Doerfler concludes that a classic mnemonic technique is much
more likely than more mysterious synesthetic landscapes in the representation of numbers.
Readers are referred to Doerfler analyses [10] for many more signatures of classical MA procedures
observed in Tammet prodigious calculations .
Of course above and beyond RTs, brain response can be used with increasing efficacy to infer
mental algorithms (REFS). The brain responses of Tammet when memorizing series of numbers
seem consistent with the hypothesis that he is using classic mnemonic techniques, even ifoften
these studies concluded the opposite [20]. Tammet´s pattern of activation while memorizing was
similar to what had been previously found by MA performing the same task using a widely known
memory technique referred as the Memory Palace [21]. This is consistent with Eleanor Maguire
finding [22] who studied MA and found that there was nothing exceptional about the anatoimcal
structure of the brains of MA. Instead all functional differences could be explained by a different
structuring of the task based on classic mnemonic techniques.
The data hence suggests that Tammet uses standard techniques . While nobody doubts his
exceptional mental achievements, he is probably being misleading about his methods to seek
glamour and popularity. What is somehow paradoxical is that these tricks may have been more
effective to convince scientists than journalists and math professors. Doerfler and Foer, the principal
actors who have debunked the case of DT are not scientists. Both Doerfler and Foer are MAs and
understand the conjuring which may confuse and trick the audience. Hence, to understand why
scientists may fall in misconceptions about mental calculation and to remediate this temptation, it is
important to reveal some of the standard tricks of mental calculation. We do this in the next section.
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2. Tools to memorize random numbers and calendrical
calculation
We introduce three techniques used by mental athletes for remembering numbers.. All these
techniques have something in common: they work on the principle that images can be remembered
more easily than numbers[18] [11].
2.1.
Mayor System
The system works by mapping numbers into consonant sounds and then into words by adding
vowels (which serve only to fill words but convey no information). Table I shows the most canonical
mapping. The link is phonetic; it is the sounds that matter, not the spelling.
Table I: Associated consonant sounds for each numeral
0
1
2
3
4
5
6
7
8
9
S, Z
T, D, TH
N
M
R
L
J, SH, CH, SOFT G
K, C, HARD G, CH,
Q
F, V
P, B
To use the Mayor System one must create words or sentences using the consonants associated to
the number one want to remember and any number of vowels. For instance, 3.1415927 (an
approximation of the mathematical constant pi) can be encoded as:
MeTeoR (314) TaiL (15) PiNK (927)
2.2.
The Memory Palace
The invention of this technique is attributed to Greek poet Simonides of Ceos. In its more
straightforward application, it is used to memorize a list of numbered objects by associating them to
a previously memorized list of places or objects. Note that the number of new objects capable of
being remembered equals the number of previously memorized objects (or “rooms” of the palace).
For instance, one may have memorized (in long term memory) a list of 10 ordered objects (1-table,
2- ball, 3-spon, etc.). This list is always the same. Then, when the MA is asked to remember an
arbitrary list which has TV as the second object, he will have to associate TV and ball in an image.
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The technique works by generating images which are as bizarre, colorful, and different from
anything one has seen before.
The Memory Palace can also be used to memorize string of random numbers. In its simpler form,
what one does is to use it in combination to the Mayor System. The method consist in transforming
the string of numbers into words and then images that can be used to associate them to different
rooms in the Memory Palace. For instance, if the sequence starts with the number 15, one first form
the word TaiL (T is 1, L is 5) and then, to remember that these are the first two digits, one put it in
the first room of the palace (1-table) by creating the image of a table with tail.
2.3.
Person-Action-Object
This technique (the PAO System) is the more powerful and as of today strictly necessary for world
record performance in memorizing numbers, cards, or binary digits. Paradoxically, it is not popular
in the scientific literature (compared to the memory palace for instance) [11]:
The PAO system uses the capacity to encode several digits in a single image by using the sentence
of action sentences. First, numbers (usually the 100 2 digit numbers) are represented as a person
performing an action on an object. This is the key aspect of the method: the encoding is redundant.
For instance, the number 46 might be Ginobili passing a basketball. The number 29 might be Pablo
Picasso painting in a wall. The number 35 Harry Potter grabbing a broom. Of course, these
association are completely arbitrary. The efficacy of the redundancy of the code is evident when one
wants to encode a 6 digit number, for instance 29 46 35. Then one simply needs to create an image
with the person of the first digit, the action of the second digit and the object of the third. So the
encoding of 29 46 35 would be Pablo Picasso passing a broom. Hence with a set of 100
associations (which have to be thoroughly worked out for rapid access) one can store 1.000.000
numbers. Also because these combinations tend to be bizarre (Picasso rarely passes brooms...)
they are easier to remember.
2.4.
Calendrical calculation
Calendrical calculation is probably the most studied savant ability. Paradoxically, the algorithms
employed by mental athletes are very difficult to find in the scientific literature. It is usually assumed
that it involves certain knowledge of the calendar structure,. However this is not at all necessary.
The algorithm can be used effectively even if one is ignorant of the calendar regularities used to
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derive it. We introduce the algorithm as explained in Secrets of Mental Math by Arthur Benjamin
[18], although there are many similar versions of it.
First, day of the week are mapped to numbers: 1-Monday, 2-Tuesday, and so on ending with 6Saturday and 7- or 0–Sunday. Then month are mapped to numbers using the following code:
Table II: Month Code for calendrical calculations
January
February
March
April
May
June
July
August
Septembe
r
October
November
December
6*
2
*
2
5
0
3
5
1
4
6
2
4
*In a leap year the code for January is 5 and for February is 1. A leap year occurs every four years with the
exception of years that are divisible by 100, although there is an exception to the exception: years divisible by
400 are leap years. Thus 1600, 2000 and 2400 are leap years but not 1700, 1800 or 1900.
A number is mapped to each year of the calendar as follows: for the years 2000 + x, take the
number x/4, ignoring any reminder, and add that to x. For instance, for 2014 the year code is 14 + 3
(. For years between 1900 and 1999 it is the same procedure (x is now given by 1900 + x) but
simply add 1 at the end. So, for instance, the year code for 1914 is 18. For dates in the 1800s
simply add 3 at the end (1814 is 20). Other rules need to be remembered to other centuries, but we
don’t explicit them here since the algorithm remains essentially the same.
Finally, to calculate the day of the week, one simply adds the month code, the year code and the
number of the day in the month and subtract from this result any multiple of 7. For instance
December 3, 2006 was a Sunday since:
3 (date) + 4 (December) + 7 (year code) = 14
and 14 – 14 (the closest multiple of 7) is 0. Note that one can also subtract any multiple of 7 from
the year code before adding it to the date and month code that the result keeps the same. For
instance, the year code for 1998 is 4 since 98/4 = 24 and 98 + 24 = 122 and 122 – 119 (multiple of
7) = 3 and since we are in the XX century we add one obtaining 4. So, December 3, 1998 was a
Thursday:3 + 4 + 4 is 11 and 11-7 is 4, i.e., Thursday.
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3. Typical misconceptions in extraordinary calculations by
savants
3.1 Prime recognition
Lighting calculation is commonly cited as the most preeminent savant ability, in particular
calendrical calculation and prime number recognition. The scientific literature on this subject is
however confusing and misleading. In his book “The man who mistook his wife for a hat” [23] Oliver
Sacks reports the case of twins which could perform extraordinary fast prime recognition. This case
has of course achieved a great amount of fame and impact.
Oliver Sacks claims that the twins could produce 20-digit prime numbers without having memorized
them. No one ever before or after this report has been able to reproduce anything even close to this
result (other experiments never test more than 3 digit numbers because larger targets produce
prohibitively large response times in any single case it has been tested). Its questionable aspects
are obvious, and have been explained in detail by Yamaguchi [5-6]. Here we summarize the main
arguments.
1. Oliver Sacks claims that he verified the digits produced by the twins using a book of number
table of up to 10-digit prime. However, there are 455,052,511 10-digits and smaller primes.
It is impossible to include such a huge number of numbers in a single book, with a
reasonable font size.
2. Sacks wrote about the twins 20 years after witnessing it. From the magic and scientific
literature we know that people tend to unconsciously exaggerate the remembering of an
episode when astonished [24, 25].
3. If the history is partially true, the twins could had use trial and division since they might have
had context-dependent division abilities.
4. This result has never been reproduced. Not even something close to it.
The critique to this case is very different to the one argued before in the case of DT. Sacks report is
completely honest; all the elements of the story (the fact that it is a single case, witnessed many
years ago, without ever being reproduced and even the fact that he was unsure about the details of
the book) are clearly stated in the book or in later communications. The critique, if any, is how the
scientific community drives conclusions from this single and influential case to sustain the belief that
extraordinary calculation is related to anatomical abnormalities in the brain. Surprisingly, to our
knowledge, the twins were never again investigated carefully in their ability to perform prime
recognition.
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3.2 Calendrical Calculators
“If savants do not mention calculation even when they can be observed to be calculating, then what
they do not say about their method is inconclusive about the basis of their skill”.
Richard Cowan and Chris Frith [26]
In 2009 Cowan and Frith published an article in which they debunked many myths about autistic
savant calendrical calculators [26]. Particularly they discuss why some researchers reject standard
calculation as a basis for their skill: 1) because calculation draws on cognitive processes that
constitute general intelligence which is impaired in autism, 2) because autistic savants (most
notably in Sack´s twins) often lack even basic arithmetical skills and 3) because they are typically
unable to give an account of how they solve date questions. Cowan and Frith have rejected these
qualitative views by demonstrating a quantitative relation between calendrical calculation and
cognitive skills such as calculus ability or general intelligence. They could derive this conclusion by
understanding which tests were more effective to measure these abilities without contamination
from other cognitive abilities which might be impaired in autism.
Above and beyond these arguments, here we focus on the fact that calendrical calculation is a
classic mentalists demonstration, because it has the virtue to appear much more difficult than it
really is. In fact, as pointed out by Arthur Benajamin [18], “With just a little bit of practice, you can
quickly and easily determine the day of the week of practically any date in history”. It is explained
also in the book “Thirteen Steps to Mentalism” by Tony Corinda [27], originally published as thirteen
smaller booklets as a course in mentalism, and later, in 1961, republished as a book. It is
considered by most magicians until today to be a classical text on mentalism (“The Bible” for many)
and was already published when scientific literature started to report cases of autistic savants
performing calendrical calculations. In other words, all autistic savant studied until today may had
easy access to the algorithm. This fact which is commonplace in the magic literature is mostly
ignored in scientific studies of calendrical calculators.
3.3 Extrasensory perception!
In this article we reviewed misconceptions about savant performance in mathematical calculus.
Savants have also been pointed as exceptional talents in other domains of cognition such as
drawing or music. An extensive review of these skills is beyond the scope of this perspective.
However, it seems natural to raise the same healthy skepticism about these demonstrations. We
focus in a single case. Dr. Darold Treffert investigation of the now famous autistic savant, Stephen
Wiltshire. This is the description of the case: [28]: “Stephen Wiltshire can certainly replicate in
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stunning fashion what he sees as demonstrated in a recent documentary film clip, when, after a 45
min helicopter ride over Rome, he completed, in a three-day drawing marathon, an impeccably
accurate drawing, on a five and half yard canvas. It captures with precision the many square miles
he has seen street by street, building by building and column by column.” The videos on Wiltshire
are everywhere in the internet and his extraordinary claims are usually cited in the scientific
literature on autistic savant. This anecdotal report influences the general public as well as
specialized scientists. However, to our knowledge, no single study has been made that could
corroborate, quantify and understand the mechanisms beyond such demonstration. This is quite
astonishing because it seems quite simple to inquire: it would suffice to take SW to a flying
simulator and precisely quantify how much could he memorize. All his drawing represent cities that
he knew in advance he would need to draw and in no case is clear if someone was controlling that
he does not consult the internet. The simple hypothesis that Wiltshire is not saying the true about
his method can easily and should be tested.
In main stream scientific journals, Darold Treffert has also argued that extrasensory perception is
among one of many savant skills. On a 2013 report to the Wisconsin Medical Society entitled
“Extraordinary telepathy as a savant skill” the argument was pushed even further on the
extraordinary virtues of savants [29]: “In our 2010 savant syndrome registry, which included 319
savants worldwide, paranormal, psi or related phenomenon were reported in 1% of cases. Now
comes this article titled “Miracle Girl” by Sajila Saseendran from the Khaleej Times, Dubai, which
documents in unusual detail the telepathic ability of a 9-year-old girl to read her mother’s mind. The
article also cites a letter from child psychiatry specialists in Sunny Specialty Medical Center in
Sharjah, United Arab Emirates, certifying witnessing “the strength of Nandana to read her mother’s
thoughts, desires and intentions.”
4. Conclusion
These arguments would raise all alarm signals to Stanley, the skeptic character of Magic in the
Moonlight. We believe they should also raise alarm signals in a skeptical cognitive neuroscience
community. Here we have raised several arguments which we believe generate misconceptions in
prodigious and exceptional performers: 1) over reliance in anecdotes and non-reproduced individual
cases, 2) errors in the methods to evaluate the capacities of savants and hence making their
performance seemingly more exceptional than it really is, 3) ignorance about techniques which
today are standards of mentalism by which performers can achieve fates with seem exceptional just
with some training.
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The last argument is particularly important as a scientific construct. Why would DT or any other
performer prefer to show themselves as virtuosos rather than "simply" the result and consequence
of tremendous effort and practice? Can they lie about their method? People like James Randi and
Michel Shermer spend their lives debunking faking demonstrations and they repeatedly recognize
that 1) people tend to lie about their methods preferring to be "geniuses" than "hard workers" and 2)
this is as necessary for scientific progress as many times unpleasant.
The reason why people lie about their methods is transparent and has been clearly expressed by
Tony Corinda, the "godfather" of mentalism [27]. “Fortunately, not everybody knows about
mnemonics and since they exist in the mind only it is difficult to tell when they are being used,
which of course makes it a good thing for the mentalist. Your protection against discovery is to
make every effort to keep the science a secret. It is tempting at times to tell your audience that you
have not used trickery as they suppose—but used a memory system which you have developed in
the mind. Let me put it this way. You will have seen the well known effect called the "Giant Memory"
where some twenty or thirty objects called out by the audience have been memorised by the
performer. This is a wonderful thing, it is very impressive, it appears incredible—but if every
member of your audience knew that given a week's practice they could do the same—how good
would be the effect? Don't try and fool yourself that the ability to do the "Giant Memory" is an
outstanding achievement. It is not. Any person of average intelligence could do it with twenty words
after a few hours study. The only thing that you have got that they have not—is the knowledge of
how to do it—and if you keep that a secret the effect remains as it is—a masterpiece”.
Even young children understand that calculations are more impressive if they do not rely in
standard techniques as using their fingers. They naturally try to impress others performing
calculations hiding the fact that they are counting with their fingers. Calculations seem obviously
more impressive if they mysteriously pop-out in the air from unexplained virtues of an unexplained
brain. The task of cognitive neuroscience is the opposite. It is to find and reveal the trick and seek to
unfold which operations (often much more normal than they seem) result in these seemingly
extraordinary performances.
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