RORβ is a key layer 4 transcription factor orchestrating a critical juncture in barrel development where terminal differentiation and activity inputs are integrated to drive cellular organization in the cortex.

New evidence challenges the long-held view that motor cortex lacks a fourth layer, and reveals that its circuitry resembles that of other cortical regions more than previously thought.

Layer 4 neuronal identity is specified by Protocadherin20 positioning the neurons into layer 4 so that they receive a positional cue from thalamocortical axons.

Neocortical synapses in layer 4 of the human temporal lobe neocortex were quantitatively characterized, at the subcellular level, using high-end, high-resolution electron microscopy and 3D-volume reconstructions.

Touch information is represented with minimal noise in the somatosensory cortex during tactile exploration.

Layers 1 and 3b/4 of auditory cortex receive surprisingly heterogeneous but tonotopically matching input from the thalamus.

The binocular matching of thalamic inputs to layer 4 cortical neurons initiates before that of intracortical inputs.

The three main types of inhibitory neurons in mouse primary visual cortex respond differently to locomotion in darkness and during visual stimulation, revealing context-dependent responses to changes in behavioral state.

In the visual system, three rules guide the thalamocortical connectivity of cortical fast-spike interneurons and are key to understand the potent and broadly tuned feed-forward inhibition that they generate.

Accumulation of perineuronal nets around parvalbumin (PV)-positive inhibitory interneurons closes visual cortical plasticity by selectively down-regulating thalamic synapses onto PV cells in a sensory-dependent manner.