Savants are people who despite serious mental or physical disability have quite remarkable, and sometimes spectacular, talents. This is an exceedingly rare phenomena, although there are several well documented cases (see Sacks, 1986; 1995; Treffert, 1989), and recently the Academy Award winning movie Rain Man has led to the term savant being much more widely known. Savant syndrome is perhaps one of the most fascinating phenomena in the study of human differences and cognitive psychology. It is often claimed that, because of the extraordinary abilities involved, we will never truly understand human memory and cognition until we understand the savant.

Savant syndrome was first properly recognised by Dr. J. Langdon Down, (n.b. he also originated the term Down’s syndrome). In 1887, he coined the term "idiot savant" - meaning low intelligence, and from the French, savoir, knowing or wise, to describe someone who had "extraordinary memory but with a great defect in reasoning power." This term is now little used because of its inappropriate connotations, and the term savant syndrome has now been more or less adopted. Another term, autistic savant, is also widely used, but this can be somewhat misleading. Although there is a strong association with autism, it is certainly not the case that all savants are autistic. It is estimated that about 50% of the cases of savant syndrome are from the autistic population, and the other 50% from the population of developmental disabilities and CNS injuries. The estimated incidence of savant abilities in the autistic population is about 10%, whereas the incidence in the learning disability population (which is very much larger) is probably less than 1%. Nevertheless, in order to understand savant syndrome, it is helpful to know something about autism, also it is important to realize that there is some confusion over these estimates of the incidence of the syndrome which stems from the different ways in which it is defined and described.

Autism is a moderately rare condition resulting from a complex developmental disability that typically appears during the first three years of life. It is a neurological disorder that affects the functioning of the developing brain, resulting in sometimes profound communicative, social and cognitive deficits. Autism is estimated to occur in as many as 1 in 500 individuals, and is four times more prevalent in boys than girls and does not seem to be associated with any demographic features, such as economic, class, racial, ethnic, etc. Autistic traits are also sometimes observed in connection with other developmental disabilities, and CNS injuries.

The term autistic was first used by Eugen Bleuler in 1908, but the condition of autism was first named and described by the psychiatrist, Leo Kanner, in a landmark paper published in 1943. It is a condition in which children and adults typically have a lowered level of intelligence, together with difficulties in verbal and non-verbal communication, in the skills of social interaction, and in play activities. The disorder makes it hard for them to relate to the outside world, and there is a marked tendency to withdraw from human interactions and become preoccupied with attachment to objects. There is a failure in human intersubjectivity, characterized by difficulties in joint action, turn taking, and shared activities. Aggressive and/or self-injurious behaviour may well be present. Often there will be continuous repetition of body movements (hand flapping, rocking), a rigidity of actions, resistance to changes in routine, and a "desire" for sameness. Independently of Kanner, in 1944 Hans Asperger, an Austrian physician, described a very similar condition, although there were some subtle differences. In 1981, Lorna Wing adopted the term Asperger’s syndrome in referring to a group of people who did not fit the strict criteria for autism, and were relatively high functioning (see Happé, 1994 for a fuller account).

It is probably best to think of autism as a spectrum disorder. For example, DSM-IV includes autism, grouped together with several related disorders, under the broad heading "Pervasive Developmental Disorder (PDD)." This is a general category of disorders which is characterized by severe and pervasive impairment in several areas of development. There are no medical criteria for diagnosing autism, a specific diagnosis is made when a specified number of characteristics are noted as present, based on the presence of specific behaviours indicated by observation and through parent consultation. Individuals who fall under the PDD category in DSM-IV exhibit commonalties in communication and social deficits, but may differ in terms of severity. Defining autism as a spectrum disorder, recognizes that the symptoms and characteristics of autism can present themselves in a wide variety of combinations, which may also range from mild to severe. Clearly, there is no standard "type" or "typical" person with autism, and the terminology in use includes: autistic traits, autistic tendencies, autism spectrum disorder, high-functioning or low-functioning autism. However, this lecture is not concerned directly with autism, its definition or diagnosis.

Savant syndrome is exceedingly rare, but a remarkable condition in which persons with autism, or other serious mental handicaps, or major mental illness, have astonishing islands of ability or brilliance that stand out in stark contrast to their overall disability. The condition can be congenital or be acquired by an otherwise normal individual following CNS injury or disease. It occurs in males more frequently than in females in an approximate ratio of 6 to 1. The skills can appear suddenly, without explanation, and have been reported as sometimes disappearing just as suddenly. It is useful to put these special skills into the following three categories: Splinter Skills where the individual possesses specific skills that stand in contrast to their overall level of functioning, Talented Savants where the individual displays a high level of ability that is in contrast to their disability, and Prodigious Savants which involves a much rarer form of the condition, where the ability or brilliance is not only spectacular in contrast to the disability, but would be spectacular even if viewed in a non-disabled person. It is very likely that many savants do go unnoticed, and depending upon whether the three categories above are recognized, estimates of the incidence of savant syndrome can vary widely. In the case of prodigious savants it has been estimated that there may be fewer than 100 cases reported in the world literature in the past 100 years.

Savant skills occur within a narrow but fairly constant range of human mental functions. If they have anything in common it is that they all more or less involve considerable feats of memory. In some cases a specific skill might exist, while in others there may be several skills that co-exist simultaneously. An important observation is that the skills tend to be right hemisphere oriented: i.e. non-symbolic, artistic, concrete, directly perceived. Table 1 describes some of the striking abilities that have been found in savants.

The reason why some autistic and disabled individuals have savant abilities is not understood, however, the strong link with autism does offer a good starting point. There have been many theories, but it is clear that no one theory is sufficient. Theories include: Biological-Developmental - such as genetic, neurochemical, left hemisphere dysfunction, frontal and temporal lobe damage, and the DSM IV diagnostic category is Pervasive Developmental Disorder (PDD); Cognitive - such as deficits in executive function and abstract thinking; weak coherence theory; highly developed procedural memory and eidetic imagery (Happé, 1994; Schopler & Mesibov, 1995). Other theories include a deficit in theory of mind (Frith, 1989), compensation for sensory disabilities (especially blindness) and social isolation, and the modularity of mind hypothesis which proposes that particularly when executive cognitive functions are disrupted the mind exhibits a striking modular organization (see Smith & Tsimpli, 1995). However, any theory would need to explain the link with autism, the islands of exceptional ability, the bias towards male savants, and recent research that includes a finding of the emergence of savant abilities in fronto-temporal dementia patients, and the suggestion of a neurotoxic effect of circulating testosterone on the left hemisphere in the male fetus possibly related to autism.

There are two necessary components of the savant syndrome: (i) a remarkable ability to memorize, to record detail, or repeat an operation endlessly and efficiently, and (ii) a means of giving expression to this ability. The importance of (ii) should not be underestimated. Not only are savants noticed by this expression of their special abilities, but also savants like doing something, and doing it again, again and again. No one has any idea how many savants go unnoticed. In the case of prodigious savants it is possible that early recognition and careful encouragement are important contributory factors to how the talent develops. It has been proposed that helping the savant to achieve a higher level of general functioning may result in a loss of the special savant skills. However, there is little evidence for this, and it may well be that "training the talent" could be a valuable approach towards improving socialization, communication and self-esteem.

Tim has profound sensory and communicative disabilities (his identity has been concealed). He lives in a residential home with day care facilities for adults with learning difficulties, and has been in residential or institutional care since the age of 15. He has no hearing and consequently no speech. He has moderate physical difficulties and sometimes he requires a wheelchair. Tim has probably been disabled since very early childhood, and it is believed that he has been diagnosed as having "autistic traits." But, as far as it is known, his medical records have been destroyed. He has a previous history of challenging behaviour and mood swings, which has in the past been controlled with powerful anti-psychotic drugs. These have been greatly reduced over the 5 years that he has been living at his current residential home, during which time there have been striking changes in his behaviour, including a particularly marked reduction in his challenging behviour. The most likely reason for this is due mainly to communication barriers being greatly decreased. Despite Tim’s profound disabilities, he is relatively outgoing and is not withdrawn, and he shows a remarkable intelligence (although this would be very difficult to measure formally). He is strong willed, and will only do things that he wants to do. He is helpful, he values affection, and he is considerate to other residents, especially in being tolerant of younger residents. Tim has probably received very little education, he cannot read or write (although he can recognize his name and a few words, and copy any shape that he wishes), but he has been taught a system of alternative communication called Makaton. This is a visual and signing process, usually used alongside speech, which is widely used in the UK by people with learning disabilities. The Makaton Vocabulary was designed in 1972 by Margaret Walker, a UK Speech and language Therapist. She developed Makaton in response to the needs of deaf adults with severe learning disabilities, particularly who were residents in an institution, because other sign communication systems were not very satisfactory. Without Makaton, Tim would only be able to make himself understood with a few crude gestures, and his life could and would be very confusing and frustrating. Tim uses Makaton to initiate conversations, to ask questions, and clarify any situation.

When placed within the context of all these disabilities, Tim possesses extraordinary abilities which primarily are illustrated by his drawing and his photographic memory. As far as it is known, these extraordinary abilities have gone unnoticed, or unrecognized, for most of his life. It was my wife, Elaine, who was the first to recognize Tim’s special abilities. It seems very clear that Tim falls into the category of a savant. What is particularly interesting is that very few cases of savants who are profoundly deaf have ever been documented (the one exception seems to be the case of James Henry Pullen, see Treffert, 1989). I will demonstrate what I am talking about by showing you a selection of his drawings. I will point out a number of features that show how his abilities fit well with those usually attributed to savant syndrome (see Table 2). His drawings are deceptively simple, and it is easy to underestimate the level of his achievements. I will draw especially upon the work of David Hockney (2001) who has recently uncovered some of the techniques used by the old masters in their paintings. Tim has very little difficulty drawing images in accurate perspective that the old masters could only do with sophisticated technical aids. What most people, including skilled artists, would find very difficult to do "by eye", Tim can do with little effort, from memory, sometimes months later, and without any formal instruction or training.

At this time, Tim is clearly a talented savant, he may even be prodigious. His special skills and abilities are highly specialized, and are obviously conspicuous when viewed over against his over-all handicap, he can draw in ways that most professional artists would find impossible. Tim seems to fit with one view of savant syndrome as resulting from a compensation for a sensory deficit, i.e. his deafness, and the possession of a remarkable photographic memory. My wife has adopted the position that Tim’s drawing ability would not have become so apparent if the communication barriers had not been bridged. Tim has a need to be sure of, and trust, what is happening around him. Without this need being met, Tim’s exceptional abilities would not have had the chance to develop in the way that they have. Indeed, it is highly unlikely that they would ever have been noticed at all.

http://www.bol.ucla.edu/~changc/index.html

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