Altered Functional Connectivity in a Mouse Model of Fragile X Syndrome

  • Miguel Dasilva
  • Alvaro Navarro-Guzman
  • Luca Maiolo
  • Andres Ozaita
  • Maria V. Sanchez-VivesEmail author
Conference paper
Part of the Advances in Cognitive Neurodynamics book series (ICCN)


We evaluated the integrity of the cortical network in the Fmr1 knockout mouse model of fragile X syndrome (FXS) by recording micro-electrocorticogram (ECoG) activity and measuring functional connectivity, alongside the degree of clustering (modularity) and integration capacity (path length). We found that functional connectivity is increased at both the short- and long-range levels, especially in prefrontal areas in the FXS model. This correlates with a decrement in the degree of cortical network clustering, together with an anomalously high information exchange capacity at high-frequency oscillatory bands. We conclude that the cognitive deficits manifested in FXS could be associated with the state of over-synchronization of the cortical network, which is more evident at high-frequency oscillatory bands and at frontal areas of the brain.


Cortex Fragile X syndrome Functional connectivity Integration Segregation 



Funded by EU H2020 Research and Innovation Programme, Grant 720270 (HBP SGA1), BFU2014-52467-R (MINECO), BFU2015-68568-P (MINECO/FEDER, UE), FLAGERA-PCIN-2015-162-C02-01, FRAXA Research Foundation, and CERCA (Generalitat de Catalunya). We thank Ernesto Pereda de Pablo (Universidad de La Laguna) for his valuable suggestions for the analysis. We also thank Guglielmo Fortunato (CNR) for the collaboration on the design and fabrication of the electrodes.


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Miguel Dasilva
    • 1
  • Alvaro Navarro-Guzman
    • 1
  • Luca Maiolo
    • 2
  • Andres Ozaita
    • 3
  • Maria V. Sanchez-Vives
    • 1
    • 4
    Email author
  1. 1.Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS)BarcelonaSpain
  2. 2.Istituto per la Microelettronica e Microsistemi (CNR)RomeItaly
  3. 3.Universitat Pompeu Fabra (UPF)BarcelonaSpain
  4. 4.ICREABarcelonaSpain

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