Pyramidal neurons in prefrontal cortex receive subtype-specific forms of excitation and inhibition

Neuron. 2014 Jan 8;81(1):61-8. doi: 10.1016/j.neuron.2013.10.031. Epub 2013 Dec 19.


Layer 5 pyramidal neurons comprise at least two subtypes: thick-tufted, subcortically projecting type A neurons, with prominent h-current, and thin-tufted, callosally projecting type B neurons, which lack prominent h-current. Using optogenetic stimulation, we find that these subtypes receive distinct forms of input that could subserve divergent functions. Repeatedly stimulating callosal inputs evokes progressively smaller excitatory responses in type B but not type A neurons. Callosal inputs also elicit more spikes in type A neurons. Surprisingly, these effects arise via distinct mechanisms. Differences in the dynamics of excitatory responses seem to reflect differences in presynaptic input, whereas differences in spiking depend on postsynaptic mechanisms. We also find that fast-spiking parvalbumin interneurons, but not somatostatin interneurons, preferentially inhibit type A neurons, leading to greater feedforward inhibition in this subtype. These differences may enable type A neurons to detect salient inputs that are focused in space and time, while type B neurons integrate across these dimensions.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / drug effects
  • Action Potentials / physiology
  • Animals
  • Calcium / metabolism*
  • Channelrhodopsins
  • Dependovirus / physiology
  • Electric Stimulation
  • Excitatory Postsynaptic Potentials / drug effects
  • Female
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • In Vitro Techniques
  • Male
  • Mice
  • Nerve Net / drug effects
  • Nerve Net / physiology*
  • Neural Inhibition / drug effects
  • Neural Inhibition / physiology*
  • Neural Pathways / physiology*
  • Neurotransmitter Agents / pharmacology
  • Patch-Clamp Techniques
  • Prefrontal Cortex / cytology*
  • Pyramidal Cells / drug effects
  • Pyramidal Cells / physiology*
  • Synapses / classification*
  • Synapses / physiology*
  • Transduction, Genetic


  • Channelrhodopsins
  • Neurotransmitter Agents
  • enhanced green fluorescent protein
  • Green Fluorescent Proteins
  • Calcium