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Savant Syndrome:
New Advances and New ResourcesThree Australian researchers
have used rTMS (repetitive transcranial magnetic stimulation) to test
the theory that higher cortical mechanisms and cognitive processing
which normal persons use in day to day functioning are such that they
over-lay and bury access to lower level savant circuitry and processes
that might lie in all of us. That idea is explored also on the
"Is
there a little 'Rainman' in each of us" portion of this web site. By
temporarily disabling these higher level processes, using rTMS, the
researchers designed tests and procedures to search for such buried
circuitry in 17 non-savant volunteers. The theory behind that research,
and its results, are summarized in a new section on this site entitled:
In
Search of the Savant Within Us Using rTMS.
The Savant Syndrome in Autism is an up to date review
chapter by Dr. Treffert in a new book entitled AUTISM:CLINICAL AND
RESEARCH ISSUES edited by Accardo, Magnusen and Capute, York Press,
Baltimore, 2000. This chapter summarizes early descriptions, present
knowledge of this condition in Autistic Disorder, some well known
autistic savants, theories to explain the savant, Williams Syndrome and
Autistic Disorder, and present day research on the interface between
autistic disorder and savant syndrome. It contains as well an up to date
bibliography.
Blindness, Autism and Prematurity
The association of blindness, autism and autistic-like symptoms, and
savant syndrom, especially musical genius, is striking given the rarity
of each of those conditions singly. A number of such savants including
Tony, Leslie and Blind Tom, just to name several, share that remarkable
triad of handicap and special abilities. Shedding some light on the
association of the retinopathy of prematurity (ROP), formerly known as
retrolental fibroplasia, is an article by Ulla Ek and others from
Sweden, which appeared in Developmental Medicine and Child Neurology
1998 40:297-301. Several conclusions from that study are pertinent to
savant syndrom:
1. The researchers compared 27 children with retinopathy of
prematurity (ROP) to 14 children with total blindness due to hereditary
retinal disease, and entirely different entity. 15 of the 27 ROP
patients (7 boys/7 girls) had Autistic Disorder (according to DSM-IV
criteria) and four children (3 boys/1 girl) had autistic-like
conditions. 18 of the children had IQs below 79; 8 of the children had
cerebral palsy. In the comparison group with hereditary retinal diesease
2 of the 14 met criteria for Autistic Disorder but their development
differed markedly from teh other 12 children, all of whom had normal
IQ's and all of whom were in mainstream classes. Thus, there is a
decided link between blindness from ROP and autism, compared to ther
causes of blindness.
2. As I have indicated elsewhere on this site, the same damage to the
retina (which is brain tissue) in ROP, from the same causes, is
suspected of producing damage elsewhere in the central nervous system
and could play an important role in the production of autistic disorder.
Rimland had raised such a possibility in his work as early as 1950. This
study confirms that speculation in that the researchers conclude in this
study that ROP was associated with strong clinical evidence of brain
damage, and, autistic disorder is linked to cerebral damage/dysfunction
and is not primarily an effect of blindness per se.
3. I have made the distinction between Autistic Disorder (autism) as
an illness and autism (autistic like behaviors) as a symptom. The
latter, autistic-like behaviors, occur in a number of persons with brain
damage who are not autistic in terms of the specific illness of Autistic
Disorder. This study goes beyond that finding and adds another very
important and pertinent observation. Many of the children with blindness
from hereditary retinal disease, who are not autistic and had normal
IQ's, showed what are called "blindisms", or behaviors which could be
mistakenly interpreted as "autistic". These included stereotyped
behavior such as rocking, swaying and hand waving. These were more
frequent earlier in life, increased with boredom, emotion, or new and
unfamiliar settings. These behaviors were seen as "adaptive" in the
non-brain injured blind child, and define an additional category of
autistic-like behaviors that are not Autistic Disorder as such.
Artistic Savants
In work that continues to support left hemisphere dysfunction in savant
syndrome, Miller and his co-workers revisit six savant artists of the
past (Mind, Yamashita, Yamamoto, Yamamura and Nadia) and compare those
historical accounts to the careful analysis, including brain imaging (SPECT)
and neuropsychological findings, of a present day nine year old savant
artist (DB). The researchers conclude that the six artistic savants of
the past all either did have diagnostic features of autism itself or at
least one of the spectrum illnesses of Pervasive Developmental Disorder
(PDD) which includes autistic disorder. Each of the six also had
features characteristic of savant artists: restricted variation in art
themes; the preferred use of a single medium on a single topic;
repetitive behaviors; realistic renderings of objects or animals; the
compulsive need to perform; the ability to focus on a specific theme for
long periods of time; and extraordinary degree of visual and kinetic
knowledge of their topics; and neither the interest nor capacity to
study art theory. All of these skills, abilities and behaviors coalesced
finally to produce a beautiful product. With respect to these
characteristics the authors state: "These features reflect
disproportionate dysfunction of the left hemisphere, although right
hemisphere deficits are also present in autism."
DB, the only savant in whom functional imaging was performed, showed
"increased perfusion in frontal areas, an imaging feature of patients
with obsessive-compulsive disorder." He also showed "hypoperfusion in
the region of the left amygdala on SPECT."
Of particular interest is this article’s documentation of "remarkable
parallels" between these savants and the individuals that these
researchers reported earlier (see Miller et al above in this section)
who had the onset of new, savant artistic abilities as a fronto-temporal
dementia began and progressed. In those individuals the "degeneration of
the anterior temporal lobes facilitates, or even precipitates new visual
artistic skills. In some of these patients artistic interest developed
only when the left sided anterior temporal degeneration was clinically
manifest."
Overall the authors conclude "the anatomic substrate for the
savant syndrome may involve loss of function in the left temporal lobe
with enhanced function of posterior neocortex." The citation for
this article is: Hou, C, Miller, BL et al. Artistic Savants
Neuropsychiatry, Neuropsychology & Behavioral Neurology 2000m Jan:
13(1)29-38.
The 'Rain Man' In All Of Us
Savants flex unused mental muscles
February 15, 2000 By Adam Pasick
For more information:
http://www.foxnews.com/health/021500/savants.sml
The Grand Rounds section of the December, 1999 issue of CNS
SPECTRUMS: The International Journal of Neuropsychiatric Medicine
(Volume 4, No. 12 pages 57-60) presents a review article on savant
syndrome by Dr. Treffert entitled "The Savant Syndrome and Autistic
Disorder". It is a concise synopsis of past and current research
findings. The color artwork illustrating savant artistic talent as a
part of that article is one of Richard Wawro's wax oil crayon drawings
entitled The Island of Scilly.
Richard Wawro
Richard Wawro, the savant artist in Scotland, now has his own
website at:
www.wawro.net.
Blind Tom
During his lifetime from 1849 to 1908 'Blind Tom' Bethune was referred
to as "the eighth wonder of the world" and "the greatest musical prodigy
of his age". At age 11 he played at the White House and at age 16 began
a piano concert tour that took him around the world. His vocabulary was
less than 100 words but his musical repertoire was over 7000 pieces,
including about 100 of his own compositions. In Philadelphia a panel of
16 outstanding musicians of the day signed a statement that "whether in
his improvisations of performances of composition by Gottschalk, Verdi
and others; in fact in every form of musical examination--and the
experiments too numberous to mention--he showed a capacity ranking him
among the most wonderful phenomena in musical history."
The story of Blind Tom, and his incredible musical savant abilities,
is documented in detail in Extraordinary People in Chapter Two based on
descriptions by Edward Sequin and other observers of that time. A March
5, 2000 New York Times article entitled "The Legacy of a Prodigy Lost in
Mystery" provides a detailed account of Blind Tom's life as well. Now a
number of Blind Tom's original compositions such as "The Balle of
Manassas", "Water in the Moonlight" and "Oliver Galop" have been
recorded by John Davis on a Newport Classic CD entitled "John Davis
Plays Blind Tom" (NPD 85660). It is available from
www.Newport-cd.com
or other CD vendors.
A National Public Radio's Performance Today program has an hour long
audio program on Blind Tom, including some of his compositions as played
by John Davis, which can be accessed on the internet at
http://npr.org/programs/pt/news/features/990827.blindtom.html.
The Extreme Male-Brain Theory of Autism
In a book chapter entitled "The Extreme Male-Brain Theory of Autism" (Neurodevelopmental
Disorders, Helen Tager-Flusberg (Ed.) MIT Press, Cambridge, MA, 1999)
Simon Baron-Cohen discusses in depth the recent male brain/female brain
research, and its relationship to autism which can, in some 'pure' cases
of autism, can have male-female ratios as high as 9:1. Beyond autism,
the data in that chapter has some interesting implications for
understanding savant syndrome. The chapter provides evidence of
biologically based psychological gender differences and the 'male brain'
is defined.
While male brain/female brain models are not synonomous with right
brain/left brain lateralization, there are some interesting correlations
significant, perhaps, in savant syndrome which is also much more common
in males that females (approximately 4:1 to 6:1 depending on the study).
In cognition studies women (as a group) are superior to men in language
tasks, tests of social judgement, measures of empathy and cooperation,
ideational fluency and pretend play, to name some of the areas. In
contrast men (as a group) are superior to women in mathematical
reasoning, some spatial skills and target-directed motor skills, also to
name just some of the areas. These skills have some interesting
correlations with right brain/left brain savant skills.
In terms of neural substrate of the Male and Female Brain, precisely
which structures distinguish these two brains is still controversial.
However there is evidence for differences in cerebral lateralization in
these two brain types with some evidence showing the right hemisphere
cortex in the human male fetus is thicker than the left. Some reports
show that the corpus callosum is larger in female subjects which might
account for female superiority in verbal fluency.
Newly acquired artistic skills in the setting of dementia
Dr. Bruce Miller and coworkers of the University of California Los
Angles School of Medicine report in the October, 1998 Journal
Neurology on five patients with frontotemporal dementia (FTD) who
acquired new artistic skills in the setting of that particular type of
dementia. While the emergence of new savant skills following brain
damage from trauma or disease (acquired savantism) early in life has
been reported as seen elsewhere on this web site, the uncovering and
unfolding of such new savant skills in some older adults raises
interesting new questions about buried potential in all of us. As with
other savants, in FTD the creativity was visual, not verbal; the images
were meticulous copies that lacked abstract or symbolic qualities;
episodic memory was preserved by semantic memory devastated; and there
was intense, obsessive preoccupation with art skills. Like other
savants, imaging studies showed a predominance of left-brain injury. The
researchers here proposed that decreased inhibition of visual systems
involved with perception enhanced artistic interest and abilities.
Another researcher, Kapur, named such a process "paradoxical functional
facilitation," a process operative not only in these five patients, but
perhaps one operative in savant syndrome overall.
Miller, BL, Cummings J, Mishkin F, et al. Emergence of artistic
talent in frontotemporal dementia Neurology 1998;51:978-982
Kapur N. Paradoxical facilitated function in brain-behavior
research Brain 1996;119:1775-1790
Islands of Genius on audio tape
Stephen Smith of Minnesota Public Radio was producer of a National
Sciences Foundation audio tape on Savant Syndrome called Islands of
Genius which describes, and interviews, several new savants and some of
the other researchers in the United States and other countries
interested in this condition. It can be accessed at the
www.soundprint.org
web site. At this site there are on-line science projects under those
the Science and Technology projects lists Islands of Genius on live
audio tape. It can also be accessed as one of the listings via
www.goto.com under
savant syndrome.
Evidence of Left Hemisphere Serotonin Deficits in Autistic
Disorder
As pointed out elsewhere on this web site savant syndrome can be
explained, in part, by left hemisphere brain dysfunction resulting in
right brain compensation. In acquired savant syndrome, such left
hemisphere brain damage can generally be documented on various imaging
studies. However, about half of the savant cases occur in persons with
Autistic Disorders and prior imaging studies did not document left
hemisphere structural defects. Nevertheless, Autistic Disorder, as
Savant Syndrome itself, is four to six times as frequent in males than
females, and some of the testosterone/left hemisphere damage theories
may be operative. In an article appearing in the March, 1999 journal
Neurology, a researcher reported that PET brain studies (which
document brain function rather than only brain structure) suggest low
serotonin (a neurotransmitter) synthesis in left hemisphere of persons
with autistic disorder, and that neuropsychological tests in these
autistic individuals also suggest left hemisphere deficits. These
findings are interesting and relevant in that they are consistent with
left hemisphere dysfunction theories with respect to savant syndrome.
The article goes on to suggest the manner in which left hemisphere
serotonin deficits alter brain development and brain circuit pathways
early in development, and such dysfunction might be linked to changes in
brain lateralization functions with respect to the learning and memory
patterns so characteristic of autism (and savant syndrome).
Delong, RG. Autism: New data suggest a new hypothesis Neurology
19699 52:911-916
Cerebral "refreshment"
Could it be that Alzheimer's Disease, or other age-related
neurodegenerative conditions, are not due to a deterioration or loss of
a fixed population of existing brain cells, but rather are due to
a deterioration or loss of the brain's ordinary capacity to make new
cells? That intriguing possibility is raised in a brief article entitled
"Fresh Horses" by Jeff Victoroff, M.D. in the January, 2000 issue of
Psychiatric Times (pp. 17-18). In that article Dr. Victoroff
summarizes various animal and human studies that provide a basis for a
very significant paradigm shift in our thinking about brain cell renewal
and plasticity. He points out that recent discoveries that neurogenesis
(continous production of new neural cells in the brain) "might be a
routine part of the ongoing remodeling of the brain throughout human
adulthood has prompted major rethinking of our models for postnatal
development. Instead of imagining a battle between deterioration (e.g.
apoptosis) and cellular repair, we might imagine a contest between cell
loss and cell replacement." After much more exploration of the
background research for such speculation, he concludes: "We must revise
our concept of cerebral refreshment right now. Lifestyle factors
(learning, exercise, and stress avoidance) and neurorehabilitation may
not just sculpt synapses, reduce the risk of erosion of a fixed
population of postmitotic cell or recruit old neighbor cells to new
tasks. They may rebuild our brains."
What might that mean for savant syndrome? I have indicated that right
brain 'recruitment', following left hemisphere damage, is felt to be an
important etiologic factor in savant syndrome in some instances. The
concept of a continually renewing stream of neurons, or a nest of neural
stem cells "awaiting awakening into functional adult neurons" from
injury or other stimulus, rather than a fixed reservoir of brain cells
(in the right brain hemisphere or anywhere else) that has been generally
the accepted concept until now, would have implications not only for
some possible etiologic mechanisms of savant syndrome, but also for
understanding brain physiology and pathology overall, especially with
respect to brain plasticity and repair.
The information in that brief report is too detailed to adequately
summarize here. It is very well written and easily understood, though,
and contains a wealth of information on this important paradigm shift,
along with pertinent references.
Uncommon Genius
A Savant Documentary
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| Leslie Lemke |
The Australian Broadcasting Company (ABC) has recently released a
documentary video on Savant Syndrome which was filmed in the United
States in April, 2000. In 1993 Robyn Young visited a number of savants
in the U.S. as part of a group of 52 savants world-wide she eventually
was able to study using a uniform psychological history and test
protocol. This film captures her trip cross-country in the U.S
revisiting these savants seven years later, along with interviewing
various experts on savant syndrome familiar with these particular
persons. The savants Dr. Young visited included George, Tony, Leslie,
Alonzo, Kim (who are described in greater detail on this site) and
several others. Experts interviewed included Drs. Treffert, Rimland and
Bruce Miller.
The video is exceptionally well done artistically showing beautiful
glimpses of United States scenery from coast to coast along with
glimpses at savant abilities in these remarkable persons. Uncommon
Genius was shown in a 30 minute abbreviated version on the
Learning Channel in the United States in March, 2001. It was shown on
Australian Public Television in May, 2001. It is available for purchase
from the Australian Broadcasting Company through inquiry at this e mail
address:
progsales@your.abc.net.au or by inquiry at this link:
http://www.abc.net.au/programsales.
EXTRAORDINARY PEOPLE: Understanding Savant Syndrome by Dr.
Treffert has now been re-issued, with an epilogue update, by
iuniverse.com through an arrangement with Author's Guild backinprint.com.
The book is available through the
www.iuniverse.com
web site. When the title window appears type in EXTRAORDINARY PEOPLE and
ordering instructions will appear. At that web site there is a graphic
of, and additional information about, the book. The book is also
available through Barnes and Noble.com at
www.bn.com and through
Amazon.com at
www.amazon.com.
For more information, please contact:
Darold A. Treffert, M.D.
Behavioral Health Services
St. Agnes Hospital
430 East Division Street
Fond du Lac, Wisconsin 54935
920-926-4297 office
920-921-9381 home office
920-926-8933 fax
dtreffert@pol.net
Information about purchasing a documentary videotape of the Leslie
Lemke story can be obtained by writing to:
Miracle of Love Ministries
8099 Grant Road
Arpin, Wisconsin 54410
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