A complex relationship exists between mesoscopic local field potentials (LFP) and single neuron firing. Using laminar recordings from all layers in the primary visual cortex (V1) of the behaving mouse, we quantified this relationship. Depth profiles of unit power and sink-source distributions of LFP provided consistent depth landmarks across animals. Coherence of gamma oscillations (30-100 Hz) and spike-LFP coupling identified six physiological layers and sublayers. Firing rates, burstiness and other features of neurons displayed unique layer and brain state-dependence. The most prominent LFP pattern during waking was a 3–6 Hz rhythm with characteristic phase preference of spikes across layers, which we consider as an evolutionary precursor of the primate alpha oscillations. Monosynaptic connections among neurons were assessed by spike transmission probability. Spike transmission between principal cells and interneurons was stronger during waking compared to non-REM sleep, but stronger among deep layer excitatory neurons during non-REM. These results bridge mesoscopic LFP and single neuron interactions
with laminar structure in V1.