Sağlıklı Bireylerde ve Bilinç Bozukluğu Olan Hastalarda İnteroseptif Kortikal Hemodinami: Pilot Çalışma

Year 2025, Volume: 5 Issue: 14

Merve Alökten

https://doi.org/10.54270/atljm.2025.93

Abstract

Amaç: Bu pilot çalışmanın amacı, sağlıklı ve bilinç bozukluğu bulunan bireylerde dinlenim ve kalp atımı sayma görevi sırasında fonksiyonel yakın kızılötesi spektroskopi (fNIRS) ile ölçülen kortikal oksihemoglobin (HbO) yanıtlarını araştırmaktır. Çalışma, interoseptif süreçlerin bilinç mekanizmalarıyla ilişkisini anlamaya ve davranışsal ölçütlerden bağımsız biyobelirteçlerin geliştirilmesine katkı sağlamak üzere bir pilot çalışma olmayı hedeflemiştir.
Gereç ve Yöntem: Çalışmaya yaş, cinsiyet ve eğitim açısından benzeştirilmiş 13 sağlıklı birey ve 6 bilinç bozukluğu bulunan hasta dahil edilmiştir. fNIRS ölçümleri 35 kanallı NIRScout cihazı ile frontal ve parietotemporal bölgelerden alınmıştır. Dinlenim koşulunda 7 dakikalık gözler kapalı kayıt yapılmış, interoseptif görev olarak Schandry’nin kalp atımı sayma paradigması uygulanmıştır. ΔHbO yanıtları Homer3 yazılımında işlenmiş, parametrik olmayan testlerle analiz edilmiştir.
Bulgular: Dinlenim durumunda gruplar arasında anlamlı fark bulunmamıştır. Sağlıklı bireylerde kalp atımı sayma görevi sırasında sol frontal ve mid frontal bölgelerde ΔHbO düzeylerinde anlamlı azalma gözlenmiştir. Bilinç bozukluğu grubunda dinlenim ve görev koşulları arasında fark saptanmamıştır. Gruplar arası karşılaştırmalarda, sağlıklı bireylerin sol ve sağ temporoparietal bölgelerde daha düşük ΔHbO değerlerine sahip olduğu belirlenmiştir.
Sonuç: Çalışma, interoseptif görevler sırasında sağlıklı bireylerde frontal ve temporoparietal bölgelerde anlamlı hemodinamik değişiklikler görüldüğünü; bilinç bozukluğu olan bireylerde ise görevle ilişkili yanıtların belirginleşmediğini göstermiştir. Temporoparietal bölgelerdeki farklılıklar, bu alanların interoseptif farkındalık ve bilinçli deneyimle ilişkisini desteklemektedir. Bulgular, sınırlı örneklem büyüklüğüne rağmen fNIRS’in bilinç bozukluklarında biyobelirteç geliştirilmesine katkı sağlayabilecek bir yöntem olduğunu düşündürmektedir.

Keywords

İnterosepsiyon , Hemodinamikler , Fonksiyonel Yakın Kızılötesi Spektroskopisi , Bilinç Bozuklukları

Ethical Statement

Bu çalışma, İstanbul Medipol Üniversitesi Girişimsel Olmayan Klinik Araştırmalar Etik Kurulu tarafından 29/12/2021 tarihinde E-10840098-772.02-6727 karar numarası ile onaylanmıştır. Sağlıklı katılımcılardan çalışmaya katılmadan önce yazılı bilgilendirilmiş onam alınmıştır. Bilinç bozukluğu olan bireyler için ise yasal vasilerinden yazılı bilgilendirilmiş onam alınmıştır.

Supporting Institution

Bu çalışma herhangi bir kamu, ticari veya kar amacı gütmeyen kuruluştan finansal destek almamıştır.

Thanks

Bu çalışmanın kavramsal temellerine ve yürütülmesine yaptığı değerli katkılardan dolayı Prof. Dr. Lütfü Hanoğlu’na içten teşekkürlerimi sunarım.

INTEROCEPTIVE CORTICAL HEMODYNAMICS IN HEALTHY INDIVIDUALS AND PATIENTS WITH DISORDERS OF CONSCIOUSNESS: A PILOT STUDY

Abstract

Aim: The aim of this pilot study was to investigate cortical oxyhemoglobin (HbO) responses measured by functional near-infrared spectroscopy (fNIRS) during resting state and a heartbeat counting task in healthy individuals and patients with disorders of consciousness (DoC). The study sought to provide preliminary insights into the relationship between interoceptive processes and mechanisms of consciousness, and to contribute to the development of biomarkers independent of behavioral measures.
Materials and Methods: Thirteen healthy individuals and six DoC patients, matched for age, sex, and education, were included. fNIRS measurements were obtained from frontal and parietotemporal regions using a 35-channel NIRScout device. Resting-state recordings consisted of 7 minutes with eyes closed, while interoception was assessed with Schandry’s heartbeat counting paradigm. ΔHbO responses were preprocessed with Homer3 software and analyzed using non-parametric statistical tests.
Results: No significant differences were observed between groups during the resting condition. In healthy individuals, the heartbeat counting task was associated with significant decreases in ΔHbO levels in the left and mid-frontal regions. In the DoC group, no differences were found between resting and task conditions. Between-group comparisons revealed that healthy participants showed lower ΔHbO values in the left and right temporoparietal regions compared to the DoC group.
Conclusion: This pilot study demonstrated significant hemodynamic changes in frontal and temporoparietal regions during interoceptive tasks in healthy individuals, whereas no task-related responses were observed in DoC patients. Differences in the temporoparietal regions highlight their critical role in interoceptive awareness and conscious experience. Despite the limited sample size, the findings suggest that fNIRS may contribute to the development of potential biomarkers for disorders of consciousness.

Keywords

Interoceptive , Hemodynamics , Functional Near-Infrared Spectroscopy , Disorders of Consciousness

Ethical Statement

This study was approved by the Non-Interventional Clinical Research Ethics Committee of Istanbul Medipol University on 29/12/2021 with the decision number E-10840098-772.02-6727. Written informed consent was obtained from healthy participants prior to participation. For individuals with disorders of consciousness, written informed consent was obtained from their legal guardians.

Supporting Institution

This study did not receive any public, commercial, or non-profit financial support.

Thanks

I would like to express my sincere gratitude to Prof. Dr. Lütfü Hanoğlu for his valuable contributions to the conceptual foundations and execution of this study.

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