"Ongoing and sensory evoked synaptic dynamics in the barrel cortex"

Inhibitory cells constitute only a small fraction of the population of cortical neurons, yet they are central in sculpting network activities. The relation between excitation and inhibition, however, is far from being understood. In recent years in-vivo intracellular recording techniques were developed to measure the relations between excitation and inhibition in different sensory areas. In the first part of my talk I will present experiments that were aimed to find if the balance between excitation and inhibition in the somatosensory cortex during repetitive stimulation of the vibrissa depends on adaptation. The goal of the experiments that I will present in the second part of my talk was to address a long lasting debate on the instantaneous relations between excitation and inhibition. Some studies suggested that these opposing inputs balance each other only on average, when measured at time scales of many milliseconds, while others proposed a correlation on the fine millisecond scale. To address this question we developed a new approach that is based on simultaneous intracellular recordings from pairs of nearby cortical cells. Our studies suggest that the balance between excitation and inhibition depends on past history of stimulation and that inhibitory control of excitation has high temporal precision.