Lomi Eleonora, Jeffery Kate J, Mitchell Anna S
Department of Experimental Psychology, University of Oxford, The Tinsley Building, Mansfield Road, OX1 3SR Oxford, UK.
School of Psychology & Neuroscience, College of Medical, Veterinary & Life Sciences, University of Glasgow, G12 8QB Glasgow, UK.
iScience. 2023 May 29;26(7):106993. doi: 10.1016/j.isci.2023.106993. eCollection 2023 Jul 21.
The thalamus and cortex are anatomically interconnected, with the thalamus providing integral information for cortical functions. The anteroventral thalamic nucleus (AV) is reciprocally connected to retrosplenial cortex (RSC). Two distinct AV subfields, dorsomedial (AVDM) and ventrolateral (AVVL), project differentially to granular vs. dysgranular RSC, respectively. To probe if functional responses of AV neurons differ, we recorded single neurons and local field potentials from AVDM and AVVL in rats during foraging. We observed place cells (neurons modulated by spatial location) in both AVDM and AVVL. Additionally, we characterized neurons modulated by theta oscillations, heading direction, and a conjunction of these. Place cells and conjunctive Theta-by-Head direction cells were more prevalent in AVVL; more non-conjunctive theta and directional neurons were prevalent in AVDM. These findings add further evidence that there are two thalamocortical circuits connecting AV and RSC, and reveal that the signaling involves place information in addition to direction and theta.
丘脑与皮层在解剖学上相互连接，丘脑为皮层功能提供不可或缺的信息。丘脑前腹核（AV）与压后皮质（RSC）相互连接。AV有两个不同的亚区，背内侧（AVDM）和腹外侧（AVVL），分别向颗粒状与非颗粒状RSC进行不同的投射。为探究AV神经元的功能反应是否存在差异，我们在大鼠觅食期间记录了AVDM和AVVL的单个神经元以及局部场电位。我们在AVDM和AVVL中均观察到了位置细胞（受空间位置调制的神经元）。此外，我们对受θ振荡、头部方向以及二者结合调制的神经元进行了特征描述。位置细胞和θ与头部方向结合的细胞在AVVL中更为普遍；更多非结合性的θ和方向神经元在AVDM中更为普遍。这些发现进一步证明存在两条连接AV和RSC的丘脑皮质回路，并揭示除了方向和θ之外，该信号传导还涉及位置信息。
