Path Integration: Combining Optic Flow with Compass Orientation Matthew Collett, Thomas S. Collett  Current Biology  Volume 27, Issue 20, Pages R1113-R1116 (October 2017) DOI: 10.1016/j.cub.2017.09.004 Copyright © 2017 Elsevier Ltd Terms and Conditions

Figure 1 Path integration in the central complex. (A) Central complex of Megalopta genalis, showing the positions of the protocerebral bridge and the noduli. The protocerebral bridge is also shown enlarged to illustrate the organised mapping across the 16 segments of the head direction with respect to the celestial compass (taken from [3]). (B) The inputs to the eight columns of the path integration accumulators for a particular travel direction (central arrow shows travel direction with respect to head orientation). Each TN cell is tuned to a translational flow point of expansion 45° from the midline (direction relative to body axis indicated by dashed arrow). The outer circular histograms represent the outputs from the four TN cells to the eight columns of accumulators. Note that only two TN cells are active for any heading direction. The inner circles represent their inputs to the accumulator after inhibition from the celestial compass (displaced by 1 column for the TN2 cells and 3 columns for the TN1 cells). Stone et al. propose that each column of the accumulation is composed of reverberating circuits between the noduli and PB, and that the excitatory (TN) and inhibitory (TB1) inputs enter at opposite ends. Current Biology 2017 27, R1113-R1116DOI: (10.1016/j.cub.2017.09.004) Copyright © 2017 Elsevier Ltd Terms and Conditions