Heritability of Heschl's Gyrus : master thesis

Sitar, Anamarija (avtor), Golestani, Narly (mentor), Kepinska, Olga (komentor)

The human brain’s intricacies have long captivated researchers, driving them to unravel the interplay of genetics and environment in shaping its structures. Heschl’s gyrus (HG), crucial for auditory processing, exhibits notable variability among individuals and hemispheres, with structural differences linked to language proficiency, learning abilities, and dyslexia. This twin study aimed to ascertain HG heritability, focusing on cortical thickness and surface area. We hypothesized greater heritability for surface area than thickness and an estimated cortical thickness heritability of around 50%. Leveraging MRI data from 452 participants in the Human Connectome Project dataset, we employed the innovative Toolbox for the Automated Segmentation of HG (TASH) for brain segmentation. Structural equation modeling (SEM), specifically the ACE model, revealed higher heritability estimates for left hemisphere cortical thickness (55%), with bilateral thickness at 66% and right hemisphere thickness at 18%. Conversely, surface area heritability estimates were lower, with the left hemisphere at 2%, right hemisphere at -15%, and bilateral area at 7%. These results, while partially aligning with previous literature, contradict the initial hypothesis, as no significant heritability of HG surface area was detected. Despite the informative results, caution must be exercised when interpreting the heritability of HG area, as the sample power was too low to detect the higher heritability of this feature. Nevertheless, robust heritability estimates for cortical thickness align with prior literature. Future studies utilizing larger datasets can enhance statistical power, yielding more robust insights into genetic and environmental influences on cortical structure, particularly in regions like HG. Moreover, advanced segmentation tools like TASH could deepen understanding of the genetic and molecular mechanisms of HG and primary auditory regions, enriching our comprehension of auditory processing and cognitive functions.

• Jezik: Angleški jezik
• Ključne besede: Heschl’s gyrus, heritability, ACE model, brain segmentation, twin study, Human Connectome Project (HCP)
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: PEF - Pedagoška fakulteta
• Leto izida: 2024
• PID: 20.500.12556/RUL-164329
• Datum objave v RUL: 22.10.2024

Sekundarni jezik

• Jezik: Slovenski jezik
• Naslov: Dednost Heschlovega girusa : [magistrsko delo]

Izvleček

Zapletenost človeških možganov že dolgo navdušuje raziskovalce, ki si prizadevajo razvozlati medsebojno vplivanje genetike in okolja pri oblikovanju njihovih struk- tur. Heschlov gyrus (HG), ki je ključnega pomena za obdelavo slušnih informacij, se med posamezniki in hemisferami zelo razlikuje. Te strukturne razlike so povezane z znanjem jezika, učnimi sposobnostmi in disleksijo. Namen te študije dvojčkov je bil oceniti dednost HG, specifično njegove kortikalne debeline in površine. Hipoteza je predvidevala, da bo ocena dednosti površine HG večja kot ocena dednosti debeline HG in pa, da bo le ta okoli 50%. Uporabljene so bile MRI slike 452 udeležencev iz podatkovne zbirke Human Connectome Project (HCP) in inovativno orodje TASH (Toolbox for the Automated Segmentation of HG) za segmentacijo HG. Za oceno de- dnosti smo uporabili metodo SEM (Structural equation modeling), specifično model ACE. Rezultati so pokazali višje ocene dednosti za debelino skorje leve hemisfere HG (55 %), za debelino, povprečeno prek obeh hemisfer 66 % in debelino desne hemisfere 18 %. Nasprotno pa so bile ocene dednosti površine nižje, in sicer za levo hemisfero 2 %, za desno hemisfero -15 % in za površino, povprečeno prek obeh hemisfer 7 %. Ti rezultati se sicer delno ujemajo s prejšnjo literaturo, vendar so v nasprotju z našo hipotezo, saj ocena dednosti površine HG ni bila višja od ocene dednosti debeline HG. Kljub informativnim rezultatom moramo biti pri interpreta- ciji dednosti površine HG pazljivi, saj je bila moč vzorca premajhna za detekcijo višje dednosti površine HG. Ocene dednosti debeline HG so skladne s predhodno literaturo. V prihodnih študijah bi bilo dobro uporabiti večji vzorec, kar bi pove- čalo statistično moč in bi tako študije omogočile zanesljivejši vpogled v genetske in okoljske vplive na strukturo HG. Poleg tega lahko napredna orodja za segmentacijo, kot je TASH, poglobijo razumevanje genetskih in molekularnih mehanizmov HG in primarnih slušnih regij ter tako obogatijo naše razumevanje slušnega procesiranja in kognitivnih funkcij.

• Ključne besede: Heschlov girus, dednost, model ACE, segmentacija možganov, študija dvojčkov, projekt HCP