Neuronal communication: firing spikes with spikes

Spikes of single cortical neurons can exert powerful effects even though most cortical synapses are too weak to fire postsynaptic neurons. A recent study combining single-cell stimulation with population imaging has visualized in?vivo postsynaptic firing in genetically identified target cells. The results confirm predictions from in?vitro work and might help to understand how the brain reads single-neuron activity.