Optogenetic activation of the ventral tegmental area-hippocampal pathway facilitates rapid adaptation to changes in spatial goals

Yuta Tamatsu; Hirotsugu Azechi; Riku Takahashi; Fumiya Sawatani; Kaoru Ide; Fumino Fujiyama; Susumu Takahashi

doi:10.1016/j.isci.2023.108536

Optogenetic activation of the ventral tegmental area-hippocampal pathway facilitates rapid adaptation to changes in spatial goals

iScience. 2023 Nov 23;26(12):108536. doi: 10.1016/j.isci.2023.108536. eCollection 2023 Dec 15.

Authors

Yuta Tamatsu¹, Hirotsugu Azechi¹, Riku Takahashi¹, Fumiya Sawatani¹, Kaoru Ide¹, Fumino Fujiyama², Susumu Takahashi¹

Affiliations

¹ Laboratory of Cognitive and Behavioral Neuroscience, Graduate School of Brain Science, Doshisha University, Kyotanabe 610-0394, Japan.
² Laboratory of Histology and Cytology, Faculty of Medicine, and Graduate School of Medicine, Hokkaido University, Sapporo 060-8638, Japan.

Abstract

Animal adaptation to environmental goals to pursue rewards is modulated by dopamine. However, the role of dopamine in the hippocampus, involved in spatial navigation, remains unclear. Here, we studied dopaminergic inputs from the ventral tegmental area (VTA) to the hippocampus, focusing on spatial goal persistence and adaptation. Mice with VTA dopaminergic lesions struggled to locate and update learned reward locations in a circular maze with dynamic reward locations, emphasizing the importance of VTA dopaminergic neurons in the persistence and adaptation of spatial memory. Further, these deficits were accompanied by motor impairments or motivational loss even when dopamine receptors in the dorsal hippocampus were selectively blocked. Stimulation of VTA dopaminergic axons within the dorsal hippocampus enhanced the mice's ability to adapt to changing reward locations. These findings provide insights into the contribution of dopaminergic inputs within the hippocampus to spatial goal adaptation.

Keywords: Biological sciences; cognitive neuroscience; neuroscience.