VTechWorks staff will be away for the winter holidays starting Tuesday, December 24, 2024, through Wednesday, January 1, 2025, and will not be replying to requests during this time. Thank you for your patience, and happy holidays!

Browsing by Author "Middleton, Benita"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Circadian dynamics in measures of cortical excitation and inhibition balance
    Chellappa, Sarah L.; Gaggioni, Giulia; Ly, Julien Q. M.; Papachilleos, Soterios; Borsu, Chloe; Brzozowski, Alexandre; Rosanova, Mario; Sarasso, Simone; Luxen, Andre; Middleton, Benita; Archer, Simon N.; Dijk, Derk-Jan; Massimini, Marcello; Maquet, Pierre; Phillips, Christophe; Moran, Rosalyn J.; Vandewalle, Gilles (Springer Nature, 2016-09-21)
    Several neuropsychiatric and neurological disorders have recently been characterized as dysfunctions arising from a 'final common pathway' of imbalanced excitation to inhibition within cortical networks. How the regulation of a cortical E/I ratio is affected by sleep and the circadian rhythm however, remains to be established. Here we addressed this issue through the analyses of TMS-evoked responses recorded over a 29 h sleep deprivation protocol conducted in young and healthy volunteers. Spectral analyses of TMS-evoked responses in frontal cortex revealed non-linear changes in gamma band evoked oscillations, compatible with an influence of circadian timing on inhibitory interneuron activity. In silico inferences of cell-to-cell excitatory and inhibitory connectivity and GABA/Glutamate receptor time constant based on neural mass modeling within the Dynamic causal modeling framework, further suggested excitation/inhibition balance was under a strong circadian influence. These results indicate that circadian changes in EEG spectral properties, in measure of excitatory/inhibitory connectivity and in GABA/glutamate receptor function could support the maintenance of cognitive performance during a normal waking day, but also during overnight wakefulness. More generally, these findings demonstrate a slow daily regulation of cortical excitation/inhibition balance, which depends on circadian-timing and prior sleep-wake history.