Savant Syndrome: Clinical and Neuropsychological Features

Abstract

Savant syndrome defines the people who have severe developmental and mental disabilities but also have extraordinary mental skills which are missing in many people. Although general mental capacity is under average mental level, savant has excessive knowledge about one or more domains. It is accepted that as many as one in 10 persons with autistic disorder have such remarkable abilities in varying degrees, although savant syndrome occurs in other developmental disabilities or in other types of central nervous system injury or disease as well. Males outnumber females by an approximate 6 : 1 ratio in savant syndrome. Savant skills are limited to five general categories. These are music, art, calender calculating, mathematics and mechanical or spatial skills. Savant skills can also be divided into three as savants who have splinter skills, talented savants and prodigious savants. A remarkable memory welds to the special abilities determined in savant syndrome. Savant syndrome can be congenital or it can be acquired. Most often savant skills emerge in childhood, superimposed on some underlying developmental disability present at birth. However, acquired savant skills can also appear, when none were previously present, in neurotypical individuals following brain injury or disease later in infancy, childhood or adult life. Savant skills don't depend on only rote memory. It is approved that an enhanced or spared ability to represent and manipulate highly organised domain-specific information. Various theoretic models were defined to explain the neuropsychological profile in savant syndrome. Interest in savants has a long history, stretching back to the early 18th century; nevertheless, the savant syndrome remains as much a mystery now as it did when it was first described. Given that many questions about the existence and nature of savant talent remain unanswered, it seems likely that research efforts will continue unabated.

Keywords

• Savant, Autism, Memory, Talent, Savant Syndrome

Savant Sendromu: Klinik ve Nöropsikolojik Özellikleri

Öz

Savant sendromu, ağır düzeyde gelişimsel ya da zihinsel yetersizliklerin yanında çoğu insanda bulunmayan sıra dışı zihinsel becerileri olan kişileri tanımlamaktadır. Kişinin genel zeka düzeyi ortalamanın altında olmasına karşın bir ya da birden fazla alanda aşırı düzeyde bilgi sahibidir. Savant sendromu olgularının yaklaşık yarısının otistik bozukluğa bağlı, kalan yarısının da diğer tip gelişimsel bozukluklar, zeka geriliği veya merkezi sinir sistemi hastalıkları ya da yaralanmalarına bağlı olduğu kabul edilmektedir. Erkeklerde kızlara oranla altı kat daha sık görülür. Savant becerileri genellikle beş genel kategori ile sınırlıdır. Bunlar müzik becerileri, sanat becerileri; takvim hesaplama becerisi; matematik becerisi ve mekanik ya da mekansal becerilerdir. Savant olguları parçalı becerileri olan savantlar, yetenekli savantlar ve olağanüstü savantlar olarak üçe ayrılabilir. Savant sendromunda saptanan özgül becerilere hemen her zaman olağanüstü bir bellek eşlik eder. Savant sendromu konjenital ya da edinsel olabilir. Birçok savant becerisi doğumda var olan bazı gelişimsel güçlüklerin üzerine eklenerek çocuklukta ortaya çıkmaktadır. Edinsel savant becerileri sağlıklı gelişim gösteren bireylerde bebeklik, çocukluk ya da erişkinlikte geçirilen kafa travması ya da merkezi sinir sistemi travması sonrası gelişebilir. Savant becerilerinin zaman içinde kaybolması kural olmaktan ziyade istisnadır. Savantların becerileri sadece ezber belleğine dayanmamaktadır. Oldukça organize, alana özgü bilginin temsil edilme ve düzenleme becerisinin gelişmiş olduğu bilinmektedir. Savant sendromundaki nöropsikolojik profili açıklamak için birçok teorik model ortaya konmuştur. Savant olgularına olan ilgi 18. yüzyılda başlamış olmasına karşın halen ilk tanımlandığı dönemdeki gibi gizemini korumaktadır. Savant'a özgü yeteneklerin varlığı ve doğası ile ilgili birçok soru halen yanıtsız olduğundan bu konu ile ilgili araştırmalar artarak devam edecek gibi gözükmektedir.

Anahtar Kelimeler

• Savant, Otizm, Bellek, Yetenek, Savant Sendromu

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