Dopaminergic neurons promote hippocampal reactivation and spatial memory persistence.
We found that optogenetic burst stimulation of hippocampal dopaminergic fibers from midbrain neurons in mice exploring novel environments enhanced the reactivation of pyramidal cell assemblies during subsequent sleep/rest. When applied during spatial learning of new goal locations, dopaminergic photostimulation improved the later recall of neural representations of space and stabilized memory performance. These findings reveal that midbrain dopaminergic neurons promote hippocampal network dynamics associated with memory persistence.
This month Colin McNamara and colleagues report compelling evidence of how rewarding or novel experiences strengthen newly-encoded spatial memories. The hippocampus provides the brain with representations of space (J. O'Keefe and J. Dostrovsky, 1971) but newly-formed hippocampal representations may degrade with time unless stabilized by additional processes.
Published online yesterday is the latest study from Dr. David Dupret and colleagues in Nature Neuroscience.
Members of the Unit contributed to the FENS Forum 2014 held in Milan, Italy.
Dr. Peter Magill presented a symposium lecture, entitled "Functional dichotomy in the striatal-pallidal axis".
Posters given by Unit members at the Forum include:
Bazelot, M., Bocchio, M., Fischer, D., Ferraguti, F., Capogna, M. (2014) Hippocampal theta mediates disinhibition of mouse amygdala principal cells via GABAB receptors.
Bocchio, M. & Capogna, M. (2014) Serotonin switches the firing mode of nitric oxide-expressing neurons of the mouse lateral amygdala.