PhD: Maria Szlapczynska

Long-range connectivity defines learning-induced intrinsic plasticity of prelimbic neurons

Defended on June 13, 2014

The medial prefrontal cortex (mPFC) is necessary for the formation of contextual representations and memory expression following fear conditioning. Recent studies have shown learning-dependent changes in the intrinsic excitability of mPFC neurons. It is not clear, however, whether these changes are region-wide or neuron-type specific. The specific connectivity and intrinsic properties of different neuronal types could cause certain neuronal populations to be preferentially involved in information processing in a learning paradigm. In this project, we investigated this hypothesis by studying the plasticity of intrinsic excitability in the prelimbic (PL) part of the mPFC in two defined neuronal groups: those projecting to the ipsilateral amygdala and those projecting to the contralateral mPFC. We used contextual fear conditioning together with retrograde tracing and whole-cell electrophysiological recordings of labeled pyramidal neurons in adult 2-3 month old male C56BL/6J mice. We show that neurons projecting to the amygdala display learning-dependent changes in neuronal excitability following contextual fear conditioning. In contrast, the excitability of neurons projecting to the contralateral mPFC does not differ between trained and control animals. Together, these results indicate that learning-induced changes in intrinsic excitability are not generalised across all PL neurons but instead are defined by the neurons’ long-range projection targets.

PhD committee

  • Dr BONTEMPI Bruno 
    Bordeaux, France Chairman
  • Dr NOLAN, Matthew 
    Edinburgh, United Kingdom  – Reviewer
  • Prof. BASHIR, Zafar 
    Bristol, United KindgomReviewer
  • Dr FRICK, Andreas
    Bordeaux, France  – PhD supervisor

Thesis supervisor

Andreas Frick
PhD, Group Leader Neurocentre Magendie, INSERM U862 Group “Circuit and dendritic mechanisms underlying cortical plasticity” Inserm U 862
Neurocentre Magendie

Last update: 14 April 2018