Heading in the right direction

The mechanisms that rodents employ to navigate through their environment have been greatly studied. Cognitive mapping theory suggests that animals use distal cues in the environment to navigate to a goal location (place navigation). However, others have found that animals navigate in a particular direction to find a goal (directional navigation). The rodent brain contains head direction cells (HD cells) that discharge according to the head direction of the animal. Navigation by heading direction is disrupted by lesions of the anterodorsal thalamic nuclei (ADN), many of which are HD cells. Aim 1 tested whether male C57BL/6J mice exhibit direction or place navigation in the Morris water maze. Aim 2 tested the effects of temporary inactivation of the ADN on directional navigation. Together, these data indicate that C57BL/6J mice also exhibit preference for directional navigation and suggest that the ADN may be crucial for this form of spatial navigation.