A cellular mechanism underlying enhanced capability for complex olfactory discrimination learning

Naveen Chandra, Richa Awasthi, Togba Ozdogan, Friedrich W. Johenning, Barbara Imbrosci, Genela Morris, Dietmar Schmitz, Edi Barkai

Research output: Contribution to journalArticlepeer-review


The biological mechanisms underlying complex forms of learning requiring the understanding of rules based on previous experience are not yet known. Previous studies have raised the intriguing possibility that improvement in complex learning tasks requires the long-term modulation of intrinsic neuronal excitability, induced by reducing the conductance of the slow calcium-dependent potassium current (sI AHP ) simultaneously in most neurons in the relevant neuronal networks in several key brain areas. Such sI AHP reduction is expressed in attenuation of the postburst afterhyperpolarization (AHP) potential, and thus in enhanced repetitive action potential firing. Using complex olfactory discrimination (OD) learning as a model for complex learning, we show that brief activation of the GluK2 subtype glutamate receptor results in long-lasting enhancement of neuronal excitability in neurons from controls, but not from trained rats. Such an effect can be obtained by a brief tetanic synaptic stimulation or by direct application of kainate, both of which reduce the postburst AHP in pyramidal neurons. Induction of long-lasting enhancement of neuronal excitability is mediated via a metabotropic process that requires PKC and ERK activation. Intrinsic neuronal excitability cannot be modulated by synaptic activation in neurons from GluK2 knock-out mice. Accordingly, these mice are incapable of learning the complex OD task. Moreover, viral-induced overexpression of Gluk2 in piriform cortex pyramidal neurons results in remarkable enhancement of complex OD learning. Thus, signaling via kainate receptors has a central functional role in higher cognitive abilities.

Original languageEnglish
Article numbere0198-18.2019
Issue number1
StatePublished - 1 Jan 2019

Bibliographical note

Publisher Copyright:
© 2019 Chandra et al.


  • GlUk2 receptors
  • Intracellular recordings
  • Meta-learning
  • Olfactory-learning
  • Pyramidal neurons
  • Spost-burst AHP

ASJC Scopus subject areas

  • General Neuroscience


Dive into the research topics of 'A cellular mechanism underlying enhanced capability for complex olfactory discrimination learning'. Together they form a unique fingerprint.

Cite this