Neurophysiological mechanisms of sleep overheating: insights on the insular cortex connectivity
Poster No:
2582
Submission Type:
Abstract Submission
Authors:
Erfan Naghavi1, Amirhussein Abdolalizadeh2
Institutions:
1School of Medicine, Tehran university of medical sciences, Tehran, Iran, 2School of Medicine and Health Sciences, Carl Von Ossietzky Universität Oldenburg, Oldenburg, Germany
First Author:
Co-Author:
Amirhussein Abdolalizadeh
School of Medicine and Health Sciences, Carl Von Ossietzky Universität Oldenburg
Oldenburg, Germany
School of Medicine and Health Sciences, Carl Von Ossietzky Universität Oldenburg
Oldenburg, Germany
Introduction:
Sleep is a crucial factor in maintaining overall health, and its poor quality has been linked to various medical conditions, such as cardiovascular disease, cancer, and depression (Irwin 2015). Feeling overheated during sleep without any heat source, commonly referred to as hot flashes, contributes to lower sleep efficiency and perceived sleep quality (Joffe et al. 2013). The right insular cortex (rIC) is involved in linking subjective and objective sensory perceptions: the dorsal posterior part provides the foundation for the primary interoceptive representation, while the right anterior region plays an important role in subjective emotional awareness and perception of warmth (Olausson et al. 2005; Davis et al. 2023; Craig 2009). We propose that impaired connectivity between the posterior and anterior rIC may be associated with the hot flashes, irrespective of the room temperature.
Methods:
The minimally-preprocessed resting-state functional magnetic resonance imaging (rfMRI) data of the 1200 subjects human connectome project young adults (HCP-YA) was used in this study (Essen et al. 2013), including data on age, gender, depression, the Pittsburgh sleepiness questionnaire index (PSQI), while excluding participants with incomplete data (less than 4 rfMRI runs) or a positive drug test. We then included the subjects with poor sleep quality (PSQI > 5). Then, they were categorized into two groups based on the frequency of sleep disruption due to hot flashes in the last month: at least two times a week (hot sensitive group: HSG), and less than that (not-hot sensitive group: NHSG). We divided the rIC into three functional areas based on prior literature (Menon et al. 2020): dorsal anterior insula (dAI), ventral anterior insula (vAI), and posterior insula (PI). These three areas respectively correspond to AVI+MI+FOP3, AAIC, and PoI1+PoI2+Ig+FOP2 based on the Glasser's atlas (Glasser et al. 2016) (Figure 1). Pairwise functional connectivity was calculated across four functional runs, r-to-z-transformed, and averaged. We then statistically compared the pairwise functional connectivity (PI-dAI, PI-vAI, dAI-vAI) between HSG and NHSG. Age, gender, and depression were included as covariates in the analysis.
·Figure 1. The rIC components and their corresponding subdivisions.
Results:
In total, there were 245 participants, comprising 106 men and 139 women, with a mean age of 28.67 ± 3.50 years. There was no significant difference in age, gender, depression, and PSQI score between the NHSG and the HSG. The demographic data are available in detail in Table 1. Our results indicated that the functional connectivity between the PI and the dAI was significantly lower in the HSG compared to NHSG (F(1, df) = 4.387, p value = 0.037). However, the analysis did not support a significant difference in the PI and the vAI (F(1, df) = 0.539, p = 0.463), as well as the dAI and the vAI (F(1, df) = 0.349, p = 0.554) functional connectivity between the two groups (Figure 2).
·Figure 2. Comparing PI, dAI, and vAI pairwise functional connectivity between the NHSG and HSG.
Conclusions:
In conclusion, the PI and the dAI functional connectivity was significantly lower in the HSG compared to the NHSG. These findings support our hypothesis that the impaired functional connectivity between the right dorsal posterior and the anterior insular cortex may contribute to hot flashes in healthy subjects. Our findings may offer additional insights into the neurophysiological role of the insular cortex in the occurrence of hot flashes during sleep.
Modeling and Analysis Methods:
Connectivity (eg. functional, effective, structural)
fMRI Connectivity and Network Modeling
Perception, Attention and Motor Behavior:
Perception: Pain and Visceral 2
Sleep and Wakefulness 1
Keywords:
FUNCTIONAL MRI
Perception
Sleep
Other - Insula
1|2Indicates the priority used for review
Provide references using author date format
Davis, K D, G E Pope, A P Crawley, and D J Mikulis. 2023. “Perceptual Illusion of ‘ Paradoxical Heat ’ Engages the Insular Cortex,” 1248–51.
Essen, David C Van, Stephen M Smith, Deanna M Barch, Timothy E J Behrens, Essa Yacoub, Kamil Ugurbil, and Wu-minn H C P Consortium. 2013. “NeuroImage The WU-Minn Human Connectome Project : An Overview.” NeuroImage 80: 62–79. https://doi.org/10.1016/j.neuroimage.2013.05.041.
Glasser, Matthew F, Timothy S Coalson, Emma C Robinson, Carl D Hacker, John Harwell, and Essa Yacoub. 2016. “A Multi-Modal Parcellation of Human Cerebral Cortex.” Nature Publishing Group 536 (7615): 171–78. https://doi.org/10.1038/nature18933.
Irwin, Michael R. 2015. “Why Sleep Is Important for Health: A Psychoneuroimmunology Perspective.” Annual Review of Psychology 66 (January): 143–72. https://doi.org/10.1146/annurev-psych-010213-115205.
Joffe, Hadine, David P White, Sybil L Crawford, Kristin E McCurnin, Nicole Economou, Stephanie Connors, and Janet E Hall. 2013. “Adverse Effects of Induced Hot Flashes on Objectively Recorded and Subjectively Reported Sleep: Results of a Gonadotropin-Releasing Hormone Agonist Experimental Protocol.” Menopause (New York, N.Y.) 20 (9): 905–14. https://doi.org/10.1097/GME.0b013e31828292d1.
Menon, Vinod, Guillermo Gallardo, Mark A Pinsk, Van-dang Nguyen, United States, and Inria Sophia Antipolis. 2020. “Microstructural Organization of Human Insula Is Linked to Its Macrofunctional Circuitry and Predicts Cognitive Control,” 1–27.
Olausson, H, J Charron, S Marchand, C Villemure, I A Strigo, and M C Bushnell. 2005. “Feelings of Warmth Correlate with Neural Activity in Right Anterior Insular Cortex” 389: 1–5. https://doi.org/10.1016/j.neulet.2005.06.065.