1. SAVANT SYNDROME

2. What is Savant Syndrome?
“Persons with obvious mental [disability] who are
capable of performing remarkable feats in sharply
circumscribed areas at a remarkably high level”
Grossman 1983
 intellectual deficit is marked and broad
 remarkable behaviour is extraordinary in normal context

3. What is Savant Syndrome?
 Rare
 Severe mental disability
 “Island of genius” involving increased memory skills
 Link to autism:
 10% people with autism have savant syndrome
 50% people with savant syndrome have autistic spectrum disorder
 Also present in other developmental disabilities or CNS injury/disease

4. What is Autism?
 pervasive developmental disorder
 presence of abnormal/impaired development before aged 3 years
 abnormal functioning in the three areas of psychopathology:
 reciprocal social interaction
 communication
 restricted, stereotyped, repetitive behaviour
 phobias, sleep disorders, eating disorders, temper tantrums and self-directed
aggression are all also common
ICD-10 Classification

5. What is Autism?
 ICD-10 uses secondary behaviours
 Young et. al., developed the Flinders Observation Schedule of Pre-verbal
Autistic Characteristics (FOSPAC):
 focussed on pre-verbal behaviour
 not dependant on receptive language
 objectively measurable
 focussed on core deficit-linked behaviours
 poor interaction
 bizarre responses to external stimuli
 repetitive movements
(Young 2001)

6. Autism Diagnoses

7. Why Savant Syndrome?
Relevant to psychiatry:
 Responsible for increasing awareness of Autism
 “Training the talent” as a “Conduit towards normalisation”
 Brain function models must include this coexistence of mental disability and
exceptional mental ability
 Ethical issues surrounding search for a cure

8. Savant Skills
 Always related to incredible memory
 very deep and narrow, associated with particular skill
 Most commonly only one skill
 Multiple skills more common in autistic savants
Classification of savant skills
 Splinter Skills
 most common
 obsessions with/memorisation of music, trivia, maps etc.
 Talented Savants
 ability that is abnormally high in view of cognitive impairment
 Prodigious Savants
 very rare; <50 currently living
 ability considered extraordinary even if viewed in a non-impaired person

9. Savant Skills
Typically found in the following areas:
 musical ability
 art
 calendar calculating/mathematics
 mechanical/spatial skills
 Rarer skills:
 polyglot
 abnormal sensory discrimination
 ability to know how much time has elapsed
 outstanding knowledge in particular fields
 Usually right hemisphere in type

10. Kim Peek
 Macrocephaly, cerebellar damage, agenisis of corpus callosum
 First steps aged 4 years
 Motor difficulties
 Photographic memory
 Reading
 10 seconds/page
 recall 12,000 books
 Calendar calculation skills
 Learning piano
 Sense of humour developing

11. Daniel Tammet
 Autistic savant
 Congenital childhood epilepsy
 Mathematics, sequence memory, language skills
 Synesthesia
 π recalled to 22,514 digits
 English, French, Spanish, German, Finnish, Lithuanian,
Estonian, Icelandic and Esperanto
 Created Mänti language

12. Alonzo Clemons
 Head injury as a toddler
 Limited language
 Clay sculpting talent
 20 mins observation of TV
image
 45 mins per sculpture
 Highly accurate
 Vocabulary increasing
 Improving social competence
 More independent

13. Derek Paravicini
 Born 15 weeks premature
 0.5 Kg
 Oxygen therapy
 bind
 development affected
 Self taught piano
 Instantly recall thousands of pieces
 Can play in any key
 Jazz, Pop & Classical
 Improvisation and performance

14. How does it work?
 Numerous theories
 None are complete
 Eidetic imagery (photographic memory)
 not present in all savants
 may be simply a marker of brain damage
 Inherited skills
 not enough evidence for skills in relatives
 Rote memory
 memory cannot totally explain savant skills (Hermelin 2001)

15. How does it work?
 savant skills tend to be right hemisphere in type
 left brain dysfunction : right brain activity in autism
 PET scans have shown ↓5-HT synthesis in left hemisphere in autism
(DeLong 1999)
 Numerous case examples:
 9 year old boy
 gun shot wound to left hemisphere
 mute, deaf and paralysed
 subsequent savant mechanical skill (Brink 1980)
Right hemisphere compensation following left hemisphere injury

16. How does it work?
 Two studies by Miller and Hou:
 5 Frontotemporal Dementia patients acquired artistic skills: (Miller 1998)
 dominant left hemisphere injury
 “Loss of function in the left anterior temporal lobe may lead to the
‘paradoxical functional facilitation’ of artistic and musical skills”
 SPECT imaging of 9 year old autistic savant: (Hou 2000)
 bilateral ↑frontal lobe perfusion
 bilateral ↓anterior temporal lobe perfusion
 worse on the left
 “The anatomic substrate for the savant syndrome may involve loss of function in
the left temporal lobe with enhanced function of the posterior cortex”

17. How does it work?
 rTMS investigations: (Snyder & Mitchell 1999)
 used to temporarily halt left hemisphere functioning
 5/17 saw ↑in savant-type skills
 savant-type skill possible for some, not all
 savant processes in the brain occur in everyone but are drowned out by
higher functioning cognition
 savant syndrome individuals have “privileged access to lower levels of
information not normally available through introspection”

18. How does it work?
 However, some argue against this hypothesis:
 prosodic features of speech (usually right hemisphere mediated) may be
absent in savants
 melody recall is associated with left hemisphere
 absolute pitch associated with larger planum temporale in left hemisphere
Multiple-site model of autism
 autism shows several sites of pathology
 one of these sites is the basis for savant skill
 temporal and parietal polysensory areas
 preservative attention and expanded primary pattern extraction
 modality-specific information
 predicts only some people with autism will develop savant skills

19. Savant Syndrome
 rare
 intellectual deficit
 “island of genius”
 link to autism
 right hemisphere compensation following left hemisphere injury
 multiple-site model of autism
 possible future advances in our knowledge and understanding
 “acquired” savant syndrome
 hidden potential in us all?

20. www.savantsyndrome.com
Darold A. Treffert, MD

21. References
Treffert, D.A. Savant Syndrome: An Extraordinary Condition – A Synopsis: Past, Present, Future.
Hermelin, B. (2001). Bright Splinters of the Mind. London: Jessica Kingsley Publishers.
Young, R. (2001). Current research in the area of Autism and Savant Syndrome. International Education
Journal, 2(4):329-333.
Hou, C., Miller, B.L., Cummings, J. (2000). Artistic savants. Neuropsychiatry Neuropsychol. Behav. Neurol.,
13:29-38.
DeLong, R. (1999). Autism: new data suggests a new hypothesis. Neurology, 52:911-916.
Miller, L.K. (1999) The Savant Syndrome: Intellectual Impairment and Exceptional Skill. Psychological
Bulletin, 125(1): 31-46.
Snyder, A., Mitchell, D. (1999). Is integer arithmetic fundamental to mental processing? Proc. Royal Soc.
London Biol. Sci., 266:587-592.
Miller, B.L., Cummings, J., Mishkin, F. (1998). Emergence of artistic talent in fronto-temporal dementia.
Neurology, 51:978-982.
Rimland, B., Fein, D.A. (1988) Special Talents of autistic savants. In: The Exceptional Brain:
Neurophysiology of Talent and Special Abilities. Obler, L.K., Fein, D.A., eds. New York: Guilford Press.
Grossman, H. (1983) Classification in mental retardation. Washington, DC: American Association on Mental
Deficiency: 179.
Brink, T. (1980). Idiot savant with unusual mechanical ability. Am. J. Psychiatry, 137:250-251.
Giray, E.F., Barclay, A.G. (1977). Eidetic imagery: longitudinal results in brain-damaged children. Am. J.
Ment. Defic., 82:311-314.

22. Acknowledgements
http://www.wisconsinmedicalsociety.org
http://www.derekparavicini.net
Autism graph: www.fightingautism.org
Alonzo Clemons Photos: http://artsales.com/ARTists/Alonzo_Clemons/index.html
http://en.wikipedia.org/wiki/Image:Rain_Man_poster.jpg