Circuit defects in the neocortex of Fmr1 knockout mice
Wednesday 12th of March 2014 at 12:00pm
Subtle alterations in how cortical network dynamics are modulated by different behavioral states could disrupt normal brain function and underlie symptoms of neuropsychiatric disorders, including fragile X syndrome (FXS). Using two-photon calcium imaging and electrophysiology we recorded spontaneous neuronal ensemble activity in mouse somatosensory cortex. We find that unanesthetized Fmr1–/– mice exhibit abnormally high synchrony of neocortical network activity. Neuronal firing rates are also 3-fold higher in Fmr1–/– mice when the animals are in slow wave sleep or quiet wakefulness. Combined EEG/calcium imaging experiments confirmed that neurons in mutant mice have abnormally high firing and synchrony during sleep/rest. We conclude that cortical networks in FXS are hyperexcitable in a brain state-dependent manner during a critical period for experience-dependent plasticity. These state-dependent network defects could explain the intellectual, sleep and sensory integration dysfunctions associated with FXS.
Join Email List
You can subscribe to our weekly seminar email list by sending an email to
email@example.com that contains the words
subscribe redwood in the body of the message.
(Note: The subject line can be arbitrary and will be ignored)