Otizm Spektrum Bozukluğunda El 2D:4D Parmak Oranı ve Yüz Simetrisi

Otizmin etiyolojisi ile ilgili birçok teori vardır ve en çarpıcı olanı anne karnında testosterona maruz kalma teorisidir. Bu çalışmada, otizm spektrum bozukluğu (OSB) tanılı erkek çocuklar ve normal gelişimi olan çocuklarda ikinci ile dördüncü parmak ve yüz ölçümlerinin simetrik olup olmadığı araştırılmıştır. Çalışma için, OSB tanısı konan 30 erkek çocuk, normal gelişim gösteren 30 erkek çocukla karşılaştırılmıştır. Her bireyin yüz fotoğrafları dijital ortamda çekilmiş ve yüz yarılarında sekiz farklı referans uzunluğunda ölçüm yapılmıştır. Otizm tanısı alan çocuklarda yüz yarısı ölçümleri kendi aralarında ve normal sağlıklı gelişimi olan kontrol grubu ile karşılaştırılmıştır. Ek olarak simetri tespiti için sağ ve sol eller fotoğraflanarak ikinci (2D) ve dördüncü (4D) parmakların uzunlukları ölçülerek simetri düzeyi analiz edildi. Yüz ve parmak analizi sonucunda OSB'li bireylerin yüzlerinin normal gelişim gösteren bireylere göre daha simetrik olduğu ve 2B-4B parmak uzunluklarının normal gelişim gösteren çocuklara göre birbirine daha yakın uzunlukta olduğu belirlendi. Ayrıca otizmin şiddeti arttıkça hem yüzde hem de parmaklarda simetri eğiliminin arttığı tespit edildi. Yüzde ve elde tespit edilen simetriye eğilim, otizmli bireylerin anne karnında maruz kalınan yüksek testosteron seviyesi ve buna bağlı olarak aşırı erkek beyni teorisi ile uyumludur.

Anahtar Kelimeler:

otizm spektrum bozukluğu, otizm, simetri, yüz simetrisi, 2D:4D parmak oranı

Symmetry of Hand 2D:4D Digit Ratio and Face in Autism Spectrum Disorder

There are many theories about the etiology of autism, and the most striking is the theory of testosterone exposure in the womb. In this study, it was investigated whether the second and fourth finger and face measurements were symmetrical in boys with autism spectrum disorder (ASD) and children with normal development. For the study, 30 boys diagnosed with ASD were compared with 30 normally developing boys. Photographs of each individual's face were taken digitally and measurements were made at eight different reference lengths on the face halves. Half-face measurements in children diagnosed with autism were compared among themselves and with the control group with normal healthy development. In addition, the symmetry level was analyzed by photographing the right and left hands and measuring the lengths of the second (2D) and fourth (4D) fingers for symmetry detection. As a result of the face and finger analysis, it was determined that the faces of the individuals with ASD were more symmetrical than the individuals with normal development, and the 2D-4B finger lengths were closer to each other than the children with normal development. In addition, it was determined that as the severity of autism increased, the tendency for symmetry increased in both the face and fingers. The tendency to symmetry detected in the face and hand is compatible with the high testosterone level exposed in the womb of individuals with autism and, accordingly, the excessive male brain theory.

Keywords:

autism spectrum disorder, autism, symmetry, facial symmetry, 2D:4D ratio,

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