Venue: Neurocentre Magendie
Defense in english
Yacine Tensaouti
Team: Wolff (INCIA)
Thesis supervisor: Shauna Parkes
Title
Contribution of the rat insular cortex to stimulus-guided action
Abstract
Every day, individuals are faced with numerous decisions that shape their behavior. The factors influencing these choices are multifaceted and encompass a range of considerations. Immediate needs and desires often play a significant role in action selection, guided by the value of the outcome. However, it is crucial to recognize the impact of environmental stimuli. For instance, stimuli associated with food can not only direct us toward nourishment but also trigger cravings, even in the absence of hunger. To uncover the role of the rat insular cortex (IC) in stimulus-guided actions directed towards obtaining food outcomes, we used the Pavlovian-to-Instrumental Transfer (PIT) paradigm. Given the well-established role of IC in encoding and tracking general and specific outcome-expectancies, and its critical contribution in choice guided by specific-outcome values, we hypothesized a role of the IC during the PIT transfer test where actions are influenced by reward-predictive stimuli. Using chemogenetics, we demonstrated that IC inhibition during both general and specific transfer tests abolished the ability of Pavlovian reward-predictive stimuli to energize instrumental responding, and to specifically bias action selection towards the same outcome as the presented predictive stimulus, respectively. These results demonstrated for the first time the critical role of the IC in stimulus-guided choice, encompassing both the general motivational properties acquired by Pavlovian stimuli and their ability to specifically bias action selection towards specific outcomes. Moreover, preliminary results suggest that the latter may critically depend on an intact cortico-thalamic pathway involving the mediodorsal part of the thalamus. In conclusion, we provide the first evidence that the GC is required for both general and specific forms of PIT, with the latter depending on an intact cortico-thalamic pathway.
Publications
- Yu, TS., Tensaouti, Y., Stephanz, E.P., Chintamen, S, Elizabeth, E. Rafikian, E.E., Yang, M. & Kernie, S.G. (2021) Astrocytic ApoE underlies maturation of hippocampal neurons and cognitive recovery after traumatic brain injury in mice. Communications Biology. 4, 1303.
- Tensaouti Y, Yu TS, Kernie SG (2020) Apolipoprotein E regulates the maturation of injury-induced adult-born hippocampal neurons following traumatic brain injury. PLOS ONE 15(3): e0229240. 8
- Tensaouti Y, Stephanz EP, Yu TZ, and Kernie SG (2018). ApoE regulates the development of adult newborn hippocampal neurons. eNeuro. July/August, 5(4) e0155-18.2018 1-15. Accompanied by press release from the Society of Neuroscience.
- Yu TS, Tensaouti Y, Bagha ZM, Davidson R, Kim A, and Kernie SG. (2017) Adult newborn neurons interfere with fear discrimination in a protocol-dependent manner. Brain and Behavior. Aug 2;7(9): e00796. PMID 28948089.
Jury
Claire RAMPON, DR, CNRS, Univ. Toulouse III – Présidente, examinatrice
Fabien NANEIX, Lecturer, Univ. Aberdeen – Rapporteur
Sébastien CARNICELLA, DR, INSERM U1216, Univ. Grenoble – Rapporteur
Shauna PARKES, CR, CNRS UMR 5287, Univ. Bordeaux – Directrice de thèse