Extended Data Figure 5: Statistics of firing fields in the SMT.

a, Number of firing fields per cell for all 2,208 CA1 cells. Error bars, 95% multinomial confidence intervals. The count includes fields before joystick press and after joystick release. However, MEC cells did occasionally have more than one field even during sound presentation (for example, cell 5 in Fig. 4b). b, Distribution of all 1,252 CA1 firing fields throughout the SMT. Each field is assigned a time according to the time of occurrence of its maximum firing rate. Time is linearly warped between the press and the release of the joystick. c, Field width as a function of field time within the task. Fields were sorted by their time in the task, and a rolling window of 100 fields was applied. The average field time within the task and the average field width were measured in this window (black trace). Blue band shows s.e.m. of field width within the rolling window. d, Field height (peak firing rate) as a function of field time within the task. Data are plotted as in c. Fields were concentrated near the press and the release of the joystick and were narrower during these times. e–h, Statistics in MEC for 943 fields in 1,164 cells, plotted as in a–d. MEC tended to have more fields per cell than CA1, but otherwise had similar statistics. A tightening of firing fields in the vicinity of joystick presses and releases may be due to a higher density of available sensory cues during these events. Alternatively, field tightening may result from the stronger salience of these events compared to the rest of the task.