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Updated: Jul 15, 2026
08:02
Generation of Local CA1 γ Oscillations by Tetanic Stimulation
Published on: August 14, 2015
Developmental expression of endogenous oscillations and waves in the auditory cortex involves calcium, gap junctions,
V C Kotak1, M Sadahiro, C P Fall
1Center for Neural Science, 4 Washington Place, New York University, New York, NY 10003, USA. kotak@cns.nyu.edu
Neuroscience
|May 5, 2007
Summary
Early brain waves (OWs) in developing auditory cortex (ACx) involve calcium, gap junctions, and GABAergic transmission. These neuronal oscillations are crucial for neural circuit maturation before hearing onset.
Area of Science:
- Neuroscience
- Developmental Neuroscience
- Computational Neuroscience
Background:
- Neuronal oscillations and population waves (OWs) are hypothesized to play a critical role in the maturation of neural circuits in the developing central nervous system (CNS).
- Understanding the developmental trajectory and underlying mechanisms of these early network activities is essential for comprehending brain development.
Purpose of the Study:
- To investigate endogenous network activity, specifically OWs, in the developing auditory cortex (ACx) of gerbil pups during the first three postnatal weeks.
- To explore the network ensemble correlates of these OWs using intracellular calcium imaging.
- To determine the role of calcium, gap junctions, and GABAergic transmission in these propagating activities.
Main Methods:
- Whole-cell and paired extracellular recordings were performed in gerbil ACx slices.
- Population intracellular free calcium (Ca2+) imaging was utilized using fura-2 AM.
- Pharmacological manipulations included [Ca2+]i chelator (BAPTA), gap junction blocker (mefloquine), and GABAA receptor blocker (bicuculline).
Main Results:
- Spontaneous multi-neuronal bursts propagated from the perirhinal cortex to the ACx.
- OWs were observed from postnatal day (P) 2-5, waned after P7, and ceased after hearing onset (P12).
- Propagating waves were dependent on intracellular calcium, gap junctions, and GABAergic transmission.
Conclusions:
- Endogenously generated, propagating OWs involving calcium, gap junctions, and GABAergic transmission exist in the developing gerbil ACx.
- These activities correlate with key developmental milestones, such as hearing onset.
- Such propagating network activity is speculated to be integral to the postnatal maturation of the auditory cortex.
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