A5059849461- Neural dynamics and brain function
- Neuroscience and Neuropharmacology Research
- Photoreceptor and optogenetics research
- Retinal Development and Disorders
- Memory and Neural Mechanisms
- Visual perception and processing mechanisms
- Functional Brain Connectivity Studies
- Neuroscience and Neural Engineering
- Neonatal and fetal brain pathology
- Autism Spectrum Disorder Research
- Genetics and Neurodevelopmental Disorders
- Neural and Behavioral Psychology Studies
- Advanced Memory and Neural Computing
- EEG and Brain-Computer Interfaces
- Ion channel regulation and function
- Neurogenesis and neuroplasticity mechanisms
- Anesthesia and Neurotoxicity Research
- Sleep and Wakefulness Research
- Motor Control and Adaptation
- Genetics, Aging, and Longevity in Model Organisms
- Apelin-related biomedical research
- Atomic and Subatomic Physics Research
- Creativity in Education and Neuroscience
- Behavioral and Psychological Studies
- stochastic dynamics and bifurcation
George Washington University
2015-2024
Massachusetts Institute of Technology
2003-2017
Aix-Marseille Université
2010-2013
Inserm
2010-2013
Institut de Neurobiologie de la Méditerranée
2010-2012
McGovern Institute for Brain Research
2003-2007
Yale University
2000-2003
University of Michigan–Ann Arbor
1996
During development, formation of topographic maps in sensory cortex requires precise temporal binding thalamocortical networks. However, the physiological substrate for such synchronization is unknown. We report that early gamma oscillations (EGOs) enable spatiotemporal neonatal rat whisker system. Driven by a thalamic oscillator and initially independent cortical inhibition, EGOs synchronize neurons single barreloid corresponding barrel support plasticity at developing synapses. propose...
During development, the brain’s “inhibitory” neurons act in a diverse manner, exciting hippocampus but inhibiting sensory cortex.
A comprehensive developmental timeline of activity in the mouse cortex vivo is lacking. Understanding changes that accompany synapse and circuit formation important to understand mechanisms by which molds circuits would help identify critical checkpoints for normal development. To key principles cortical maturation, we systematically tracked spontaneous sensory-evoked with extracellular recordings primary visual (V1) nonanesthetized mice. During first postnatal week (postnatal days P4-P7),...
A primary feature of the preterm infant electroencephalogram is presence large infra-slow potentials containing rapid oscillations called slow activity transients (SATs). Such has not been described in animal models, and their generative mechanisms are unknown. Here we use direct-current multisite extracellular, as well whole-cell, recording vivo to demonstrate existence regularly repeating SATs visual cortex rats before eye opening. Present only absence anesthesia, at postnatal day 10–11...
Spontaneous retinal waves are critical for the development of receptive fields in visual thalamus (LGN) and cortex (VC). Despite a detailed understanding circuit specializations retina that generate waves, whether central also exist to control their propagation through pathways brain is unknown. Here we identify developmentally transient, corticothalamic amplification drive as mechanism wave transmission infant rat brain. During period connections excite LGN, rather than driving feedforward...
In the premature infant, somatosensory and visual stimuli trigger an immature electroencephalographic (EEG) pattern, "delta-brushes," in corresponding sensory cortical areas. Whether auditory evoke delta-brushes cortex has not been reported. Here, responses to were studied 46 infants without neurologic risk aged 31 38 postmenstrual weeks (PMW) during routine EEG recording. Stimuli consisted of either low-volume technogenic "clicks" near background noise level neonatal care unit, or a human...
The ability to generate behaviorally appropriate cortical network states is central sensory perception and plasticity, but little known about the timing mechanisms of their development. I paired intracellular extracellular recordings in visual cortex awake infant rats determine synaptic circuit regulating development a key state, persistent stable subthreshold membrane potential ( V m ) depolarization associated with wakefulness/alertness networks, called “desynchronized” or “activated”...
Children with Fragile X syndrome (FXS) have deficits of attention and arousal. To begin to identify the neural causes these deficits, we examined juvenile rats lacking mental retardation protein (FMR-KO) for disruption cortical activity related Specifically, switching visual cortex between activated inactivated states that normally occurs during movement quiet rest, respectively. In both wild-type FMR-KO rats, third fourth postnatal weeks periods was dominated by an state prominent 18–52 Hz...
Two major checkpoints of development in cerebral cortex are the acquisition continuous spontaneous activity and modulation this by behavioral state. Despite critical importance these functions, circuit mechanisms their remain unknown. Here we use rodent visual system as a model to test hypothesis that locus change responsible for developmental continuity state dependence measured sensory is relay thalamus, rather than local cortical circuitry or interconnectivity two structures. We conducted...
Abstract Fragile X syndrome (FXS) is characterized by sensory hyper-sensitivity, and animal models suggest that neuronal hyper-excitability contributes to this phenotype. To understand how dysfunction develops in FXS, we used the rat model (FMR-KO) quantify maturation of cortical visual responses from onset responsiveness prior eye-opening, through age equivalents human juveniles. Rather than hyper-excitability, before eye-opening had reduced spike rates an absence early gamma oscillations,...
Maturation of excitatory synaptic connections depends on the amount and pattern their activity, activity can affect development inhibitory synapses as well. In superficial visual layers superior colliculus (sSC), developmental increases in effectiveness γ-aminobutyric acid (GABA A ) receptor–mediated inhibition may be driven by maturation inputs. rat sSC, GABA receptor currents significantly jump amplitude between postnatal days 17 18( P17 P18), approximately when effects cortical inputs are...
Abstract During a short perinatal interval, N‐methyl‐D‐aspartate receptor (NMDAR) function is essential to process in which spontaneous retinal waves focus axon arbors the superficial layers of rodent superior colliculus (sSC). Here we provide evidence that this NMDAR‐dependent axonal refinement occurs through elimination uncorrelated synapses arising from disparate loci, rather than stabilization topographically appropriate inputs. The density synaptic release sites within fluorescently...
We explored the potential for cFOS expression as a marker of functional development “resting-state” waking activity in extended network hippocampus and entorhinal cortex. examined sleeping awake mice at (P)ostnatal days 5, 9, 13, 17 well adulthood. find that is state-dependent even 5 old, with reliable staining occurring only mice. Even during waking, was rare weak P5. The septal nuclei, cortex layer (L)2, anterodorsal thalamus were exceptional they had robust P5 similar to or greater than...
We have investigated the role of NMDA glutamate receptor (NMDAR) in genesis and regulation structural plasticity during synaptogenesis visual layers rat superior colliculus (sSC). In this neuropil, three projections compete for synaptic space development. By fluorescently labeling both eyes imaging them with confocal microscopy, we can quantify sprouting ipsilateral retinal projection that follows removal a portion contralateral and/or corticocollicular projection. Using these techniques...
NMDA receptors (NMDARs) play an important role in the structural maintenance and functional strength of synapses. The causal relationship between these anatomical roles is poorly defined. Using quantitative confocal microscopy, synaptic vesicle immunoreactivity, differential label retinal projections, we measured axon volume synapse density along ipsilateral axons (ipsi axons) sprouting into superficial visual layers superior colliculus (sSC) deafferented by a contralateral lesion (a...
Synchronous firing among the elements of forming circuits is critical for stabilization synapses. Understanding nature these local network interactions during development can inform models circuit formation. Within cortex, spontaneous activity changes throughout development. Unlike adult, early occurs in discontinuous population bursts separated by long silent periods, suggesting a high degree synchrony. However, whether micro-patterning within unique to this age and specifically tuned...
The activity of the N-methyl-d-aspartate receptor (NR) regulates composition excitatory synapses and mediates multiple forms synaptic structural plasticity. In superficial superior colliculus (sSC) rat, NR is essential for full refinement retinotopy during development. We have examined NR's role in development by chronically treating sSC from birth with competitive antagonist (±)-2-amino-5-phosphonopentanoic acid (AP5) released slow-release polymer Elvax. Whole-cell voltage-clamp recordings...