TY - JOUR A1 - Alves, Caroline L. A1 - Toutain, Thaise A1 - Aguiar, Patricia A1 - Pineda, Aruane M. A1 - Roster, Kirstin A1 - Thielemann, Christiane A1 - Porto, Joel A1 - Rodrigues, Francisco A. T1 - Diagnosis of autism spectrum disorder based on functional brain networks and machine learning JF - Scientific Reports N2 - Autism is a multifaceted neurodevelopmental condition whose accurate diagnosis may be challenging because the associated symptoms and severity vary considerably. The wrong diagnosis can affect families and the educational system, raising the risk of depression, eating disorders, and self-harm. Recently, many works have proposed new methods for the diagnosis of autism based on machine learning and brain data. However, these works focus on only one pairwise statistical metric, ignoring the brain network organization. In this paper, we propose a method for the automatic diagnosis of autism based on functional brain imaging data recorded from 500 subjects, where 242 present autism spectrum disorder considering the regions of interest throughout Bootstrap Analysis of Stable Cluster map. Our method can distinguish the control group from autism spectrum disorder patients with high accuracy. Indeed the best performance provides an AUC near 1.0, which is higher than that found in the literature. We verify that the left ventral posterior cingulate cortex region is less connected to an area in the cerebellum of patients with this neurodevelopment disorder, which agrees with previous studies. The functional brain networks of autism spectrum disorder patients show more segregation, less distribution of information across the network, and less connectivity compared to the control cases. Our workflow provides medical interpretability and can be used on other fMRI and EEG data, including small data sets. KW - Maschinelles Lernen KW - Gehirn KW - Neuronales Netz KW - Autismus Y1 - 2023 UR - https://rdcu.be/dcwIP U6 - https://doi.org/https://doi.org/10.1038/s41598-023-34650-6 VL - 2023 IS - 13/8072 SP - 1 EP - 20 ER - TY - JOUR A1 - Alves, Caroline L. A1 - Cury, Rubens G. A1 - Roster, Kirstin A1 - Pineda, Aruane M. A1 - Rodrigues, Francisco A. A1 - Thielemann, Christiane A1 - Ciba, Manuel T1 - Application of machine learning and complex network measures to an EEG dataset from ayahuasca experiments JF - PLOS ONE N2 - Ayahuasca is a blend of Amazonian plants that has been used for traditional medicine by the inhabitants of this region for hundreds of years. Furthermore, this plant has been demon� strated to be a viable therapy for a variety of neurological and mental diseases. EEG experi� ments have found specific brain regions that changed significantly due to ayahuasca. Here, we used an EEG dataset to investigate the ability to automatically detect changes in brain activity using machine learning and complex networks. Machine learning was applied at three different levels of data abstraction: (A) the raw EEG time series, (B) the correlation of the EEG time series, and (C) the complex network measures calculated from (B). Further, at the abstraction level of (C), we developed new measures of complex networks relating to community detection. As a result, the machine learning method was able to automatically detect changes in brain activity, with case (B) showing the highest accuracy (92%), followed by (A) (88%) and (C) (83%), indicating that connectivity changes between brain regions are more important for the detection of ayahuasca. The most activated areas were the frontal and temporal lobe, which is consistent with the literature. F3 and PO4 were the most impor� tant brain connections, a significant new discovery for psychedelic literature. This connec� tion may point to a cognitive process akin to face recognition in individuals during ayahuasca-mediated visual hallucinations. Furthermore, closeness centrality and assorta� tivity were the most important complex network measures. These two measures are also associated with diseases such as Alzheimer’s disease, indicating a possible therapeutic mechanism. Moreover, the new measures were crucial to the predictive model and sug� gested larger brain communities associated with the use of ayahuasca. This suggests that the dissemination of information in functional brain networks is slower when this drug is present. Overall, our methodology was able to automatically detect changes in brain activity during ayahuasca consumption and interpret how these psychedelics alter brain networks, as well as provide insights into their mechanisms of action KW - Ayahuasca KW - Elektroencephalographie KW - Alzheimerkrankheit KW - Gehirn Y1 - 2022 U6 - https://doi.org/https://doi.org/10.1371/journal. pone.0277257 VL - 2022 IS - 12 SP - 1 EP - 26 ER - TY - JOUR A1 - Bouillet, Thomas A1 - Ciba, Manuel A1 - Alves, Caroline L. A1 - Rodrigues, Francisco A. A1 - Thielemann, Christiane A1 - Colin, Morvane A1 - Buée, Luc A1 - Halliez, Sophie T1 - Revisiting the involvement of tau in complex neural network remodeling: analysis of the extracellular neuronal activity in organotypic brain slice co-cultures JF - Journal of Neural Engineering N2 - Objective: Tau ablation has a protective effect in epilepsy due to inhibition of the hyperexcitability/hypersynchrony. Protection may also occur in transgenic models of Alzheimer's disease by reducing the epileptic activity and normalizing the excitation/inhibition imbalance. However, it is difficult to determine the exact functions of tau, because tau knockout (tauKO) brain networks exhibit elusive phenotypes. In this study, we aimed to further explore the physiological role of tau using brain network remodeling. Approach: The effect of tau ablation was investigated in hippocampal-entorhinal slice co-cultures during network remodeling. We recorded the spontaneous extracellular neuronal activity over two weeks in single-slice cultures and co-cultures from control and tauKO mice. We compared the burst parameters and applied concepts and analytical tools intended for the analysis of the network synchrony and connectivity. Main results: Comparison of the control and tauKO co-cultures revealed that tau ablation had an anti-synchrony effect on the hippocampal-entorhinal two-slice networks at late stages of culture, in line with the literature. Differences were also found between the single-slice and co-culture conditions, which indicated that tau ablation had differential effects at the sub-network scale. For instance, tau ablation was found to have an anti-synchrony effect on the co-cultured hippocampal slices throughout the culture, possibly due to a reduction in the excitation/inhibition ratio. Conversely, tau ablation led to increased synchrony in the entorhinal slices at early stages of the co-culture, possibly due to homogenization of the connectivity distribution. Significance: The new methodology presented here proved useful for investigating the role of tau in the remodeling of complex brain-derived neural networks. The results confirm previous findings and hypotheses concerning the effects of tau ablation on neural networks. Moreover, the results suggest, for the first time, that tau has multifaceted roles that vary in different brain sub-networks. KW - Neuronales Netz KW - Alzheimerkrankheit KW - Gehirn KW - Schnittpräparat Y1 - 2022 U6 - https://doi.org/DOI 10.1088/1741-2552/aca261 VL - 2022 IS - November SP - 1 EP - 2 ER -