Diseases and Disorders

Savant Syndrome

Unaiza Naeem


Abstract

“Savant”, or ‘knowledgeable person’, is derived from the French word ‘saviour’ meaning ‘to know’ [1]. It was Dr. J. Langdon Down who,  125 years ago, described savant as a distinct condition. Savant syndrome occurs when a person with below-average intelligence displays a special talent or ability in a specific area.The term autistic savant is frequently heard as forms of developmental conditions such as autism are present[2]. As  Dr.David Hiles of De Montfort University aptly states, “A savant has extraordinary memory but with a great defect in reasoning power" [3].                                                                              

 

What Is It?

Savant syndrome is a rare but remarkable condition in which persons with developmental disabilities, including  autistic disorder, brain injury, or brain disease have some spectacular “islands" of skill or ability that stand in jarring, marked contrast to overall handicap [4] . The condition can be congenital (genetic),can be acquired later in childhood, or can begin even in adulthood. The savant skills co-exist with or are superimposed upon various developmental disabilities including autistic disorder, or other conditions such as mental retardation, brain injury. The extraordinary skills are always linked with prodigious memory of a special type, exceedingly deep, but very narrow. Savant skills are characterized by its domain-specificity, enhanced memory capability, and excessive focus on low-level perceptual processing. In addition, impaired integrative cognitive processing such as social cognition or executive function, restricted interest, and compulsive repetition of the same act is observed in savant individuals [5].  

  

Causes and Risks

Some researchers think that savants may have some brain injury or abnormality on the left side of the brain, the side which controls language, or to other areas of the brain which control abstract thinking. While this may be true for some savants, others show normal electrical activity in the brain when they are tested [6]. Another explanation involves left brain injury with right-brain compensation. The two brain hemispheres do tend to have specialized functions and the skills most often seen in savants are those associated with the right hemisphere, and those most lacking are those associated with the left hemisphere. Several cases studied thus far document left hemisphere damage on CT and MRI scans, and those imaging studies are also correlated with corresponding left-sided deficits on detailed neuropsychological testing. PET studies have also shown particular defects in the left hemisphere function in autistic persons, with confirming left-sided findings on neuropsychological tests. A theory that offers plausible explanations for savant abilities states that pneumo encephalograms demonstrated left hemisphere abnormalities, particularly in the left temporal lobe areas.  Supportingly, in a study of seventeen autistic patients, fifteen of the seventeen patients had left hemisphere abnormalities and four had savant skills in music or mechanical interest areas. In addition to left-brain injury and right brain compensation, in the savant, it is postulated that there is corresponding damage to the higher-level cognitive or semantic memory circuitry, with enhanced compensatory function in the lower level, more primitive, habit or procedural memory circuitry. This results in reliance on the characteristic automatic memory. Such left-brain damage/right brain compensation, coupled with semantic memory damage and procedural memory compensation, produces then the emergence of right-brain skills coupled with automatic memory typically and characteristically seen in savant syndrome [7].

Some experts suspect that developmentally disabled savants have inherited two separate genes, one for mental retardation and one for the special ability; however, only some savants have family histories that contain special skills. Some researchers have speculated that autistic or developmentally disabled persons may receive only a limited amount of sensory stimulation. This low level of stimulation might be due to biological causes or because such people are sometimes ignored by others and live in relative isolation. According to this theory, the resulting boredom could lead to the development of super-intense concentration levels as seen in savants that normal people are unable to achieve. However, this accounts for only some savants. Another theory holds that since savants cannot think abstractly, they come to rely entirely on concrete thinking, channeling all of their mental energy into one form of expression, be it art or calendar calculating [6]. Certain risks associated with the syndrome is a family history of having the savant condition, mental illness in the family, prematurity in infants where the gestation period is less than 35 weeks, parent’s maturity (Father: over 49, Mother: over 40). Different investigations have related the abilities of the savants with chromosome 15 associated alterations, as in the case of the Prader-Willi syndrome. Asperger's syndrome in the family is also included as a risk [8].

 

Demographics

Only an estimated one out of every 2,000 developmentally disabled people living in institutions can be called a savant. It is known that the rate of savant syndrome is as much as six times higher among males than among females [6]. The left hemisphere normally completes its development later than the right hemisphere and is thus subjected to prenatal influences, some of which can be detrimental, for a longer period. In the male fetus particularly, circulating testosterone, which can reach very high levels, can slow growth and impair neuronal function in the more vulnerable, exposed left hemisphere, with actual enlargement and shift of dominance favoring skills associated with the right hemisphere. A ‘pathology of superiority’ was postulated, with compensatory growth in the right brain as a result of impaired development or actual injury to the left brain [2]. 
 

Characteristics of the Syndrome

Savant skills often appear in an individual very suddenly, rather than developing over time; the abilities are fully formed and don’t increase as the savant grows older. Savant skills disappear just as suddenly as they appeared and do not seem to require their total attention. Many can play a piece of music, draw a picture, or make complex mathematical calculations while their mind appears to be elsewhere. They seem to exercise their talents without conscious effort, as if some part of their brain, unconnected to the rest, operates automatically. a savant who, given any date in the past hundred years, could say what day of the week it fell on, might not be able to perform simple tasks like tying his shoes or catching a bus. The skills of savants appear to be almost robot-like r. For example, a musical savant may be able to reproduce a complex musical piece after hearing it once, but if the original rendition contains a mistake, the savant will repeat that mistake. Further, they do not appear to be able to reason about what they are doing. For instance, a savant who can read and perfectly memorize a book containing the complete works of Shakespeare, even to the point of being able to recite a specific page of text when given a page number, probably cannot explain what those plays and poems mean [6].

While measured IQ levels in savant syndrome are most often below 70, a low measured IQ score, or “mental retardation” either as a symptom or separate disorder, is not what determines whether a person is or is not a savant. Thus, a low IQ score, while often present in savant syndrome, is not necessarily the case in all instances, and it is not a finding essential or requisite to savant syndrome. Some savants do score in the normal or superior range on commonly used IQ tests, or at least on some of the subtests that make up the overall IQ test battery [9].

 

Types of Savants

Savant syndrome can be congenital or acquired. Congenital savant syndrome means savant skills present from birth or emerging in early childhood with conditions such as early-onset and late-onset ASD, other developmental disorders, intellectual disability, Williams syndrome, agenesis of the corpus callosum, tuberous sclerosis, hypopituitarism, or other brain disorders as the underlying disability. Acquired savant skills appear, when none were previously present, in neurotypical individuals following brain injury or disease, stroke, dementia or any other central nervous system (CNS) incident later in infancy, childhood or adult life. Savant abilities that emerge, are sometimes at a prodigious level [4]. The astonishing new abilities in the acquired savant are mostly in music [10].

Allan Synder, a neuroscientist at the University of Sydney has followed acquired savants intently. In research conducted in 2012, Synder and his colleagues gave 28 volunteers a geometric puzzle that has stumped laboratory subjects for more than 50 years. The challenge was to connect nine dots, arrayed in three rows, using four straight lines without retracing a line or lifting the pen. None of the subjects could solve the problem. The team then attached electrodes to the heads of subjects and used painless direct electrical currents to temporarily immobilize the left anterior temporal lobe. At the same time, they stimulated areas in the right anterior temporal lobe, making the neurons associated with creativity more likely to fire. This time more than 40 percent of the participants solved the problem. This experiment supports the theory that acquired savants blossom once brain areas normally held in check have become unfettered, meaning that savants can access raw sensory information normally off-limits to the conscious mind [11].

Another new category in this syndrome is the “sudden savant”. According to Darold A. Treffert, a psychiatrist who is actively engaged in research over the subject tells that “I have 14 such cases now. Ten are female and four are male. Age of onset of the new skill averages 47.2 years. The new skill was art, painting or drawing in nine cases; mathematics or calendar-calculating in four; music in one. These cases came to my attention via unsolicited emails by people seeking explanations or advice from internet searches” [10]. An ordinary person has an unanticipated, spontaneous epiphany like a moment where the rules and intricacies of music, art or mathematics, for example, are experienced and revealed, producing almost instantaneous giftedness and ability in the affected area of skill sets. Because there is no underlying disability such as that which occurs in congenital or acquired savant syndromes, technically sudden savant syndrome would be better termed sudden genius [10]. Some features of the sudden are that the skill has an abrupt onset with no prior interest in or talent for the newly acquired ability. There is no obvious precipitating event or CNS injury or disease. There is a fear of the gift and obsessive-compulsive disorder (OCD) is evidence of losing one’s mind, and a tendency to hide the new ability from others rather than display it. The new skill is accompanied by  an obsessive-compulsive (OCD) component; there is the overpowering need to play music, draw or compute. Also, sudden savants work hard at improving their craft [12].

An interesting case of the sudden savant syndrome is of the 28-year-old gentleman from Israel who describes his epiphany moment when he suddenly could play like a well-educated pianist. He knew most of what is taught in music theory. As he writes “I suddenly realized what the major scale and minor scale were, what their chords were and where to put my fingers in order to play certain parts of the scale. I was instantly able to recognize harmonies of the scales in songs I knew as well as the ability to play melody by interval recognition” [13].

Range of Skills

Considering all the abilities in the human repertoire, it is interesting that savant skills generally narrow to five general categories: music, usually performance, most often piano, with perfect pitch, although composing in the absence of performing has been reported as has been playing multiple instruments, art (usually drawing, painting or sculpting), calendar calculating mathematics, including lightning calculating or the ability to compute prime numbers, and mechanical or spatial skills, including the capacity to measure distances precisely without the benefit of instruments, the ability to construct complex models or structures with painstaking accuracy or the mastery of map-making and direction-finding. Other skills have been reported less often, including prodigious language facility; unusual sensory discrimination in smell, touch or vision including synesthesia; perfect appreciation of passing time without the benefit of a clock; and outstanding knowledge in specific fields such as neurophysiology, statistics or navigation. In Rimland's (1978) sample of 543 children with special skills, musical ability was the most frequently reported skill followed by memory, art, pseudo-verbal abilities, mathematics, maps and directions, coordination, calendar calculating and extrasensory perception. Hyperlexia, which is distinguished by precocity rather than the age-independent level of skill, has also been frequently reported in autism [1].

Generally, a single special skill exists but, in some instances, several skills exist simultaneously. It was noted that the incidence of multiple skills appeared to be higher in savants with autism than in savants with other developmental disabilities. Whatever the special skill, it is always associated with a prodigious memory. Some observers list memory as a separate special skill; however, prodigious memory is an ability all savants possess cutting across all the skill areas as a shared, integral part of the syndrome itself. Several investigators have shown that memory alone cannot fully account for savant abilities, particularly calendar calculating and musical skills. Formal testing for eidetic imagery shows that phenomenon to be present in some, but certainly not all, savants and when present it may exist more as a marker of brain damage than being central to savant abilities [1].

The most common are splinter skills, which include obsessive preoccupation with, and memorization of, music and sports trivia, license plate numbers, maps, historical facts or obscure items such as vacuum cleaner motor sounds, for example. Talented savants are those cognitively impaired persons in whom the musical, artistic or other special abilities are more prominent and highly honed, usually within an area of single expertise and are very conspicuous when viewed in contrast to overall disability. Prodigious savant is a term reserved for those extraordinarily rare individuals for whom the special skill is so outstanding that it would be spectacular even if it were to occur in a non-impaired person [1]. Savants can be creative, rather than just duplicative, and the skills increase over time on a continuum from duplication, to improvisation to creation, rather than diminishing or suddenly disappearing [15].

The Autistic Savant

Savant syndrome is preferable to ‘autistic savant’, as approximately 50 percent of persons with savant syndrome have an autistic disorder and the other 50 percent have other forms of developmental disability, mental retardation or other CNS injury or disease. Thus, not all autistic persons have savant syndrome and not all persons with savant syndrome have autistic disorder [1]. The underlying disability in congenital savants was autistic spectrum disorder in 75% of cases with various other CNS disorders in 25% of cases, in congenital savants [4].  Just like in savant syndrome, males have a greater chance of developing the autistic savant condition with the male to female ratio being 4:1[1].  It does not seem to be correlated with any demographic features, such as economic, class, racial, ethnic, etc. [3].

The two halves of the brain specialize in different tasks; in general, the right side is home to creativity and the left is the centre of logic and language. “It tends to be the dominant brain region,” says Dr. Berit Brogaard, “It tends to suppress very marginal types of thinking - highly original, highly creative thinking, because it’s beneficial for our decision-making abilities and our ability to function in normal life.”. The theory goes that as the patients’ left hemispheres became progressively more damaged, while their right hemispheres were free to flourish. One theory suggests that autism arises from abnormally low levels of serotonin in the left hemisphere in childhood, which prevents the region from developing normally. Just as with sudden savant syndrome, this allows the right hemisphere to become more active. Interestingly, many people with sudden savant syndrome also develop symptoms of autism, including social problems, OCD and all-consuming interests [19]. One famous example of autistic savant syndrome is Stephen Wiltshire, who after taking a 20-minute trip on a helicopter of New York City, complete, building-by-building rendition of that aerial view, correct in every detail, was sprawled across the paper [16].

The final sensory link between autism and savant syndrome is the presence of synesthesia, where stimuli such as letters, numbers, and sounds invoke automatic and additional sensory experiences such as colors. Synesthesia occurs at higher levels among autistic individuals with savant skills and not in those without savant skills [18].

 

Diagnosis and Treatment

Savant syndrome is diagnosed when a child's ability in one area is exceptionally higher than would be expected given his or her IQ or general level of functioning [19]. Based on the identification and definition of the characteristics of those affected, both possible developmental delays and exceptional abilities, it can be identified at the infantile stage through a clinical and psychological approach [9].

Savant syndrome is not a disease or a disorder, but a condition, so it does not have to be treated itself. The underlying disorders that usually accompany savant syndrome need to be treated, such as autism or Asperger’s disorder, and it is believed that making use of the special talent of the child with savant syndrome may help treat the child's underlying developmental disorders [19].  Treatment for savant syndrome is the same treatment as that directed toward the more basic CNS disorder. Or, in the case of persons with some other form of CNS injury, for example, it would be those treatment and rehabilitation efforts as directed toward overcoming the residual symptoms from such injury. These may include tranquilizers, antiparkinsonian drugs [20].

The special skills and abilities the savant demonstrates,however, can be used as a tool in overall treatment and rehabilitation efforts directed toward overcoming or lessening the handicaps from the more basic developmental disorder, injury or disease. In many cases, those extraordinary abilities can be used as a way of engaging the handicapped person in improved communication capacity, improved social interaction and improved mastery of even daily living skills— towards greater independence overall. In that manner, the savant skills can serve as a “conduit toward normalization.” By “training the talent,” not only does the special ability improve, but there also is an increase in language skills, socialization skills, and daily living skills. Each of those leads then to greater independence overall [20]. Important aspects like neurodevelopmental sequencing, vocational exploration and habilitation are also taken into consideration [9].


References


  1. Treffert, Darold. (27/5/09). The savant syndrome: an extraordinary condition. A synopsis: past, present, future. PubMed. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2677584/. Retrieved; 5/12/19.

  2. Treffert, Darold. (n.d).Savant Syndrome: An Extraordinary Condition,A Synopsis: Past, Present, Future. Wisconsin Medical Society. https://www.wisconsinmedicalsociety.org/professional/savant-syndrome/savant-syndrome-overview/. Retrieved; 5/12/19.

  3. Hiles, David.(n.d). Savant Syndrome. The Virtual Office of David Hiles. http://www.psy.dmu.ac.uk/drhiles/Savant%20Syndrome.html. Retrieved; 30/12/19.

  4. Treffert ,Darold., Rebedew, DL. (03/08/15). The Savant Syndrome Registry: A Preliminary Report. PubMed. https://www.ncbi.nlm.nih.gov/pubmed/26436185. Retrieved; 30/12/19.

  5. Takahata ,K.., Kato ,M. (2008). Neural mechanism underlying autistic savant and acquired savant syndrome. PubMed. https://www.ncbi.nlm.nih.gov/pubmed/18646626. Retrieved; 1/1/20.

  6. Porterfield,K.M. (n.d).Savant. The Gale Encyclopedia of Science. https://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/savant-1. Retrieved; 1/1/20.

  7. Treffert,Darold. (n.d).What causes Savant Syndrome?. Wisconsin Medical Society. https://www.wisconsinmedicalsociety.org/professional/savant-syndrome/faqs/. Retrieved; 1/1/20.

  8. Savant Syndrome-Definition, Causes and Treatment. (n.d).Diseasedic.com. https://diseasesdic.com/savant-syndrome-definition-causes-and-treatment/. Retrieved; 1/1/20.

  9. Treffert, Darold. (n.d) What is the relationship of savant syndrome to IQ?. Wisconsin Medical Society. https://www.wisconsinmedicalsociety.org/professional/savant-syndrome/faqs/. Retrieved; 2/1/19.

  10. Treffert, Darold. (25/7/18). Brain Gain: A Person Can Instantly Blossom into a Savant--and No One Knows Why. Scientific American. https://blogs.scientificamerican.com/observations/brain-gain-a-person-can-instantly-blossom-into-a-savant-and-no-one-knows-why/. Retrieved;3/1/19.

  11. Piore, Adam.( October 2018). The Amazing Science of Instant Savants. Reader’s Digest ,33-37. Retrieved;28/12/19.

  12. Gorvett,Zaria. (6/1/18). The mystery of why some people become sudden geniuses. BBC Future. https://www.bbc.com/future/article/20180116-the-mystery-of-why-some-people-become-sudden-geniuses. Retrieved;29/12/19.

  13. Treffert,Darold.(n.d). The Case of the ‘Sudden’ Savant. Wisconsin Medical Society. https://www.wisconsinmedicalsociety.org/professional/savant-syndrome/resources/articles/the-case-of-the-sudden-savant/. Retrieved; 29/12/19.

  14. Selfe,Lorna. (9/12/15). Nadia Chomyn obituary. The Guardian. https://www.theguardian.com/artanddesign/2015/dec/09/nadia-chomyn. Retrieved; 5/1/20.

  15. Treffert,Darold. (March 2014). Savant syndrome: realities, myths and misconceptions. PubMed. https://www.ncbi.nlm.nih.gov/pubmed/23918440. Retrieved; 2/1/20.

  16. What is an Autistic Savant?.(n.d).AppliedBehaviourAnalysisEdu.org.https://www.appliedbehavioranalysisedu.org/what-is-an-autistic-savant/.Retrieved;31/12/19.

  17. McGowan,Kat. (13/3/2013). Exploring Temple Grandin's Brain. Discover. https://www.discovermagazine.com/mind/exploring-temple-grandins-brain. Retrieved ; 5/1/20.

  18. Hughes, J.E.A., Ward, J., Gruffydd, E. et al.(2018). Savant syndrome has a distinct psychological profile in autism. Molecular Autism 9, 53. Retrieved;31/12/19.

  19. Savant Syndrome.(2004). Encyclopedia of Children’s Health. http://www.healthofchildren.com/S/Savant-Syndrome.html. Retrieved; 29/12/19.

  20. Treffert,Darold.(n.d). What is the ‘treatment’ for savant syndrome?. https://www.wisconsinmedicalsociety.org/professional/savant-syndrome/faqs/#q11. Retrieved;3/1/20.

Unaiza Naeem

Unaiza Naeem


Science enthusiast who came across neuroscience as a beautiful coherence between rationality, experimentation and life and which later became her haven.