Page 18 - Q. Neuroscience

[Q. Neuroscience-10]

Reciprocal connections between mediodorsal thalamus and

prefrontal cortex

Yelin Lee¹, Hyeonyeong Jeong¹, Eunji Cheong¹˙*

¹Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic

of Korea

Prefrontal cortex (PFC)–mediodorsal thalamus (MD) interactions are critical for cognition. In addition, executive
functions, such as working memory and cognitive control, majorly depend on PFC integrity. Most of the current

knowledge about the thalamocortical (TC) projection organization has been obtained by relying on neuronal circuit-

tracing approaches. However, the underlying circuits are unclear, and the results of previous studies are inconsistent.
Therefore, to investigate the connections between the MD and various PFC regions, this study focused on specific
MD–PFC connections using anterograde and retrograde tools. Anterograde and retrograde tools were injected into

the MD of mice, and different MD and PFC subdivisions were examined. In addition, the quantitative and qualitative
features of the MD–medial prefrontal cortex (mPFC) pathway were analyze using direct comparisons of labeling.

The MD received excitatory inputs from the motor area, mPFC, orbitofrontal cortex, and agranular insular cortex
and inhibitory inputs from the reticular nucleus and the zona incerta. The results provided insight into a new

corticothalamic circuit and the consciousness-related function of the MD which will help understand the TC
connectivity of this region and determine its functional role.