Goodridge J P, Dudchenko P A, Worboys K A, Golob E J, Taube J S
Department of Psychology, Dartmouth College, Hanover, New Hampshire 03755, USA.
Behav Neurosci. 1998 Aug;112(4):749-61. doi: 10.1037//0735-7044.112.4.749.
Previous research has shown that head direction (HD) cells in both the anterior dorsal thalamus (ADN) and the postsubiculum (PoS) in rats discharge in relation to familiar, visual landmarks in the environment. This study assessed whether PoS and ADN HD cells would be similarly responsive to nonvisual or unfamiliar environmental cues. After visual input was eliminated by blindfolding the rats, HD cells maintained direction-specific discharge, but their preferred firing directions became less stable. In addition, rotations of the behavioral apparatus indicated that some nonvisual cues (presumably tactile, olfactory, or both) exerted above chance stimulus control over a cell's preferred firing direction. However, a prominent auditory cue was not effective in exerting stimulus control over a cell's preferred direction. HD cell activity also was assessed after rotation of a novel visual cue exposed to the rat for 1, 3, or 8 min. An 8-min exposure was enough time for a novel visual cue to gain control over a cell's preferred direction, whereas an exposure of 1 or 3 min led to control in only about half the sessions. These latter results indicate that HD cells rely on a rapid learning mechanism to develop associations with landmark cues.
先前的研究表明，大鼠前背侧丘脑（ADN）和后扣带回（PoS）中的头部方向（HD）细胞会根据环境中熟悉的视觉地标进行放电。本研究评估了PoS和ADN的HD细胞对非视觉或不熟悉的环境线索是否会有类似的反应。在通过蒙住大鼠眼睛消除视觉输入后，HD细胞保持方向特异性放电，但其偏好的放电方向变得不那么稳定。此外，行为装置的旋转表明，一些非视觉线索（可能是触觉、嗅觉或两者兼有）对细胞偏好的放电方向施加了高于随机水平的刺激控制。然而，一个突出的听觉线索在对细胞偏好方向施加刺激控制方面并不有效。在向大鼠暴露新的视觉线索1、3或8分钟后旋转该线索，也对HD细胞的活动进行了评估。8分钟的暴露时间足以使新的视觉线索控制细胞的偏好方向，而1或3分钟的暴露仅在约一半的实验中导致控制。后一组结果表明，HD细胞依赖快速学习机制来与地标线索建立关联。
