Experimental path integration task. Top: While the Pure PI subtask consisted only of a grassy plain, the Landmark PI subtask additionally contained a central lighthouse serving as spatial cue. Middle: Each trial began with the “start phase”, where participants navigated to a basket (goal location), the location of which they should encode. In the following “outgoing phase,” they navigated to a variable number of trees (1–5) until reaching a tree containing an apple (retrieval location). Then, during the “incoming phase,” participants had to find the way back to the goal location before receiving feedback via zero to three stars according to performance based on the drop error. Basket and trees disappeared as soon as they were reached. Bottom left: Outgoing phase (dashed black line) and incoming phase (dotted black line) were quantified according to their spatial distances: outgoing distance corresponded to the cumulated distance from goal to retrieval location (dashed red line), and incoming distance to the Euclidean distance between retrieval and goal location (dotted red line). Bottom right: General PI performance was assessed via the drop error, which corresponded to the distance between response location (marked with an X) and goal location (solid red line). The drop error can further be differentiated into distance error, referring to the difference between retrieval-to-goal distance and retrieval-to-response distance (blue line), and rotation error, depicting the angle between the retrieval-to-goal path and the retrieval-to-response path (purple arc).
How does stress impact #navigational performance? This study shows that #cortisol administration impairs path integration, a specific navigational process, and reduces grid-like brain activity patterns in the #entorhinal #cortex @plosbiology.org 🧪 plos.io/3NmX3eG
