Journals / İstanbul Tıp Fakültesi Dergisi / 2026 / Cilt: 88 Sayı: 2

CORTICAL THICKNESS ALTERATIONS IN ALZHEIMER’S PROGRESSIVE MEMORY IMPAIRMENT CONTINUUM: A NETWORK PERSPECTIVE

ALZHEIMER'İN İLERLEYİCİ BELLEK BOZUKLUĞU SÜREKLİLİĞİNDE KORTİKAL KALINLIK DEĞİŞİMLERİ: AĞ PERSPEKTİFİ

Gözde Kızılateş Evin(İstanbul University, Graduate School of Health Sciences)0000-0001-5518-6015
Ali Bayram(ISTANBUL UNIVERSITY, AZIZ SANCAR INSTITUTE OF EXPERIMENTAL MEDICINE, DEPARTMENT OF NEUROSCIENCE)0000-0002-6588-3479
Elif Kurt(ISTANBUL UNIVERSITY, AZIZ SANCAR INSTITUTE OF EXPERIMENTAL MEDICINE, DEPARTMENT OF NEUROSCIENCE)0000-0003-1956-575X
Emre Harı(ISTANBUL UNIVERSITY, İSTANBUL FACULTY OF MEDICINE, DEPARTMENT OF BASIC MEDICAL SCIENCES, DEPARTMENT OF PHYSIOLOGY)0000-0002-8329-5507
Çiğdem Ulaşoğlu Yıldız(ISTANBUL UNIVERSITY, AZIZ SANCAR INSTITUTE OF EXPERIMENTAL MEDICINE, DEPARTMENT OF NEUROSCIENCE)0000-0003-1849-0055
Hakan Gürvit(İstanbul University, İstanbul Faculty of Medicine, Department of Neurology, Behavioral Neurology and Movement Disorders Unit)0000-0003-2908-8475
Tamer Demiralp(ISTANBUL UNIVERSITY, İSTANBUL FACULTY OF MEDICINE, DEPARTMENT OF BASIC MEDICAL SCIENCES, DEPARTMENT OF PHYSIOLOGY)0000-0002-6803-734X
Pages
90–97
Publication Date
2025-04-28
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Result: The results showed significant cortical thinning across the PMIC, with more pronounced reductions in the ADD group.

📌 3 Key Takeaways

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Objective & Hypothesis:Objective: Alzheimer’s Progressive Memory Impairment Contin uum (PMIC) is typically the clinical reflection of the neurofibrillary tangle (NFT) spread of Alzheimer’s disease (AD), which starts with subtle memory complaints of subjective cognitive impairment (SCI), passes through objectifiable memory problems of the am nestic mild cognitive impairment (aMCI), and finally reaches the dementia stage of multiple cognitive deficits with an amnestic core (ADD).
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Key Findings & Data:Material and Methods: The study included 88 participants: 21 with mild ADD, 34 with aMCI, and 33 with SCI.
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Conclusion & Impact:Result: The results showed significant cortical thinning across the PMIC, with more pronounced reductions in the ADD group.
🔬Design:Araştırma Makalesi
📍Scope:Comprehensive Sample
⚙️Variables:lzheimer hastalığı · hafif kognitif bozukluk · yapısal manyetik rezonans görüntüleme

Abstract

Objective: Alzheimer’s Progressive Memory Impairment Contin uum (PMIC) is typically the clinical reflection of the neurofibrillary tangle (NFT) spread of Alzheimer’s disease (AD), which starts with subtle memory complaints of subjective cognitive impairment (SCI), passes through objectifiable memory problems of the am nestic mild cognitive impairment (aMCI), and finally reaches the dementia stage of multiple cognitive deficits with an amnestic core (ADD). This study evaluated the patterns of cortical thick ness changes across the PMIC, using a network perspective to unravel structural and functional disruptions. Material and Methods: The study included 88 participants: 21 with mild ADD, 34 with aMCI, and 33 with SCI. Clinical and neu ropsychiatric evaluations were conducted, followed by structural MRI scanning for cortical thickness measurements. Vertex-wise cortical thickness analyses were conducted using ANCOVA. Age, gender, and education were covariates. Result: The results showed significant cortical thinning across the PMIC, with more pronounced reductions in the ADD group. The cortical thinning overlapped with the Default Mode Net work (DMN), Ventral Attention Network (VAN), and Frontoparietal Network (FPN). The comparison between the SCI and aMCI groups revealed no significant difference. Conclusion: Cortical thinning was evident across different stages of PMIC, with more extensive thinning in later stages. The observed network-wide pattern of atrophy that AD-like deterioration affects broader neural systems rather than isolated regions. The findings highlight the importance of a network based approach to understand AD-related structural changes and the potential for future research to integrate multimodal imaging to explore functional connectivity alongside structural atrophy.

Özet

Amaç: Alzheimer'ın İlerleyici Bellek Bozukluğu Sürekliliği (İBBS), Alzheimer hastalığında (AH) nörofibriler yumak (NFY) yayılımının klinik yansımasıdır. Bu süreç, subjektif kognitif bozukluk (SKB) olarak bilinen hafif bellek şikayetleriyle başlayıp, amnestik hafif kognitif bozukluk (aHKB) olarak adlandırılan belirginleşmiş bel lek problemlerine, nihayetinde amnestik bir çekirdekle karakte rize edilen çoklu kognitif bozuklukları içeren demans aşamasına (AHD) ulaşır. Bu çalışma, İBBS boyunca kortikal kalınlık değişim paternlerini ağ perspektifiyle değerlendirerek yapısal ve fonksi yonel bozulmaları ortaya çıkarmayı amaçlamıştır. Gereç ve Yöntem: Bu çalışmaya, 21 hafif AHD, 34 aHKB ve 33 SKB olmak üzere 88 katılımcı dahil edilmiştir. Klinik ve nöropsiki yatrik değerlendirmeler yapıldıktan sonra, kortikal kalınlık ölçüm leri için yapısal MRG taraması gerçekleştirilmiştir. Verteks-temelli kortikal kalınlık analizleri ANCOVA kullanılarak yapılmıştır. Yaş, cinsiyet ve eğitim kovaryet değişkenlerdi. Bulgular: Sonuçlar, İBBS boyunca anlamlı kortikal incelme old uğunu ve bu incelmenin AHD grubunda daha belirgin olduğunu göstermiştir. Kortikal incelme Olağan Durum Ağı (ODA), Ventral Dikkat Ağı (VDA) ve Frontoparyetal Ağ (FPA) ile örtüşmektedir. SKB ve aHKB grupları arasındaki karşılaştırmada anlamlı bir fark bulunamamıştır. Sonuç: Kortikal incelme, IBBS'nin farklı evrelerinde belirgindir ve özellikle ileri evrelerde daha yaygın görülmektedir. Ağ genelinde gözlemlenen atrofi paterni, AH-benzeri bozulmanın yalnızca izo le bölgeleri değil, daha geniş sinir sistemlerini etkilediğini gös termektedir. Bulgular, AH ile ilişkili yapısal değişiklikleri anlamak için ağ tabanlı bir yaklaşımın önemini vurgulamakta ve yapısal atrofinin yanı sıra fonksiyonel bağlantısallığı keşfetmek için ge lecekteki araştırmalara çoklu modalite görüntülemeyi entegre etme potansiyeline dikkat çekmektedir.

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Cite This Article

Evin, G. K., Bayram, A., Kurt, E., Harı, E., Yıldız, Ç. U., Gürvit, H., Demiralp, T. (2025). CORTICAL THICKNESS ALTERATIONS IN ALZHEIMER’S PROGRESSIVE MEMORY IMPAIRMENT CONTINUUM: A NETWORK PERSPECTIVE. İstanbul Tıp Fakültesi Dergisi, Cilt: 88 Sayı: 2, 90–97. https://doi.org/10.26650/IUITFD.1581821

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