Menno P. Witter Kavli Institute for Systems Neuroscience, NTNU Norwegian University of Science and Technology, Trondheim, Norway

The entorhinal cortex is a crucial component of our conscious medial temporal lobe memory system. The quest to understand this memory system after its ‘discovery’ in the late 1950th , was boosted by finding spatially modulated neurons in the hippocampus in 1971. Subsequently, many spatially modulated neurons were discovered in the entorhinal cortex as well, particularly in a part called the medial entorhinal cortex. The standard connectional scheme of the medial temporal lobe memory system is that the medial entorhinal cortex conveys spatial information to the hippocampus, the ‘where pathway’, whereas its counterpart, the lateral entorhinal cortex conveys information concerning objects, the ‘what pathway’. In my presentation I aim to present our recent findings indicating that this scheme needs to be revised. I will show that the local networks of the lateral and medial entorhinal cortex are remarkably similar and emphasize the difference in extrinsic connectivity as a major defining feature for the known functional differences. I will propose to consider the lateral entorhinal cortex as a high-order multimodal cortex, appropriately positioned to integrate representations of the external world with motivational signals, modulated by planning and decision signals originating from the amygdala and frontal cortical regions. I will then integrate this structural knowledge of entorhinal circuitry with what is known about the specific involvement of entorhinal cortex neurons in the onset of Alzheimer’s disease and argue that such an integration results in specific predictions about molecular cascades involved in, and the associated behavioral consequences of, early-stage Alzheimer’s disease.

Considering that Menno Witter, Professor at the Norwegian University of Science and Technology and member of the Kavli Institute for Systems Neuroscience, has built up a unique expertise in the study of neural networks through innovative experimental approaches;

Considering that, thanks to this expertise and to his constant curiosity as a researcher, Menno Witter has contributed to a decisive breakthrough in the understanding of the brain's system for positioning and orienting in space;

Considering that these discoveries have been awarded the most prestigious scientific prizes;

Considering that Menno Witter has been able to use his fundamental knowledge for the benefit of a better understanding of human pathologies;

Considering that Menno Witter, actor and witness of the major advances in contemporary neuroscience, intends to contribute to the promotion and dissemination of rigorous knowledge, as evidenced by his investment in numerous editorial boards of scientific journals

Considering that Menno Witter, through his activity as a visiting professor in institutions of higher learning on three continents, plays a leading role in the training and emergence of new scientific talents at the international level;

Considering that by cultivating his interest in new skills and enlightened forms of knowledge, which are values that guide him in the formation of free individuals and actors of a responsible science, Menno Witter testifies to a modern humanism shared by our academic community;

We, by virtue of the powers vested in us, appoint and declare Professor Menno Witter an honorary doctor of the UCLouvain.