Executive functions are integrative functions that include all cognitive processing necessary to perform correctly complex tasks such as perceptual analysis of the environment, selection of relevant information, attention and working memory, and temporal and/or sequential information processing. These functions allow the elaboration of response sequences, the planning of motor programs through complete execution, but also the ability to change plans when environmental signals vary or when new relevant signals appear.
From the fonctional homology between striatum (main sensory input to basal ganglia) and cerebellum on the one hand, and recent anatomical data showing connections between striatum and cerebellum via thalamic relays on the other hand, we hypothesize a prefronto-striato-thalamo-cerebellar circuit (PSTC) as a neurobiological substrate for information selection processing necessary for acquisition and automatisation of instrumental behaviors, and as a controller and/or storage site of temporal memory. Moreover, possible interactions of the amygdala system with PSTC circuit is suggested by the emotional disorder appearing in different pathologies : anxiety disorders and emotional deficits in Parkinson patients, dysphoria in Huntington patients, and affective cerebellar syndrome (affect dysregulation) in cerebellar patients.
The project of our team is organized around different stages of associative learning and retention (initiale acquisition, asymptote and habit). It includes three main lines of inquiry :
1) temporal and/or sequential information processing,
2) selection of information and cognitive optimization,
3) emotionnal modulation of these functions.
The methodology used is based on the complementarity of pharmacological, molecular, electrophysiological and behavioral techniques, in normal subjects or subjects with striatal dysfunction (model of Parkinson disease by injections of 6-OHDA or of Huntington disease: transgenic rats), with cerebellar dysfunction (lesion of deep nuclei), or with lesions of thalamic nuclei linking the striatum and the cerebellum. Studies of behaviour modulation by emotion and of the role of amygdala will complete our analyses.
Our team is part of a ’Laboratoire International Associé’ with the laboratories of Joseph E. LeDoux (NYU, USA) and Regina Sullivan (NKI/NYU, USA) and the team of Anne-Marie Mouly (CRNL, Lyon).
We have developed a franco-american network composed of 6 labs, supporting exchange of students and post-doctoral fellows, network supported by the Partner University Fund.
We also participate in a European supported network COST Action TIMELY, with labs from 22 countries.
We also collaborate with labs in Germany, with exchanges of students supported by Procope.
Our team is associated with ED419 Bio-sigNE from University Paris-Sud.