Prominent in vivo influence of single interneurons in the developing barrel cortex

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Computational Neuroscience

Background:

• Spontaneous synchronous activity is crucial for developing brain circuits.
• Ex vivo studies identified GABAergic 'hub' neurons as key orchestrators of this activity.
• All-optical methods enable in vivo investigation of neuronal circuit dynamics.

Purpose of the Study:

• To investigate the in vivo existence and function of GABAergic hub neurons in the developing brain.
• To determine if single neurons can influence population dynamics in the barrel cortex.
• To explore the role of functional connectivity in mediating neuronal influence.

Main Methods:

• In vivo calcium imaging in non-anaesthetized mouse pups.
• Holographic optical stimulation for targeted neuronal manipulation.
• Network connectivity analysis to identify hub cells.

Main Results:

• Single GABAergic neurons, but not glutamatergic neurons, significantly influence population dynamics.
• GABAergic cells exert inhibitory control over spontaneous and sensory-evoked population bursts.
• Neuronal influence correlates with functional connectivity, with highly connected hubs showing the greatest impact.

Conclusions:

• GABAergic hub neurons play a critical role in shaping cortical circuit activity in vivo.
• These hub neurons are essential for coordinating network dynamics during development.
• Hub neurons may integrate intrinsic network properties with external sensory information.