DANDI:000582

Reproducing Sargolini et al. (2006) from dandiset 000582 3

Notebook reproduce_sargolini_2006.ipynb

• ◐Partially reproducedMain text, paragraph 2; Fig. 1D; table S1Averifier disagreed at first

  The proportion of cells with grid structure depended on layer. Most well-separated layer II cells were grid cells (66 of 108), against a smaller proportion in layers III (78 of 223), V (17 of 110) and VI (42 of 186).

  The proportion of cells with a sinusoidal modulation was layer-dependent (Fig. 1D and table S1). Whereas most well-separated layer II cells had strongly periodic firing fields, only a smaller proportion of the deeper neurons had such characteristics

  Main text, paragraph 2; Fig. 1D; table S1A

  Layer II has the highest grid scores (median 0.33 against 0.10 in the deeper layers). With a grid-score threshold of 0.3, 54% of layer II cell-sessions are grid cells, more than in any other layer. Against the stricter chance level from shuffled spike trains (0.61), 22 of 70 (31%) are, the same as layer III (34%) and above layers V and VI (18% each). Whether grid cells are the majority in layer II depends on the criterion, and the paper's was not available (closed access). The dandiset is described as a sample without saying how cells were selected, and most sessions last 10 minutes.

• ✓ReproducedMain text, paragraph 5; table S1B

  The proportion of grid cells with conjunctive head-direction tuning depended on layer (66% in layer III, 90% in layer V, 28% in layer VI, none in layer II); the difference was significant across all four layers and across layers III to VI.

  The proportion of grid cells with conjunctive properties was layer-dependent (table S1). The largest proportion was encountered in layers III and V, where 66% and 90% of the grid cells had dual response properties, respectively. In layer VI, the proportion was 28%. No conjunctive cells were observed in layer II. Differences between layers were significant (all four cell layers, c(3) 0 28.4, P G 0.001; layers III to VI, c(2) 0 6.2, P G 0.05)

  Main text, paragraph 5; table S1B

  What the paper reports

  • all four layers: chi-square test, χ2(3) = 28.4, p < 0.001
  • layers III to VI: chi-square test, χ2(2) = 6.2, p < 0.05

  Head-direction tuning above chance in 58% (layer III), 91% (V) and 73% (VI) of cells against 12% in layer II, which holds within the one rat recorded in both. Conjunctive cells are 62 of 396 in the deeper layers and 2 of 43 in layer II. Uses only the 71 sessions with two tracking LEDs. Counts are of cell-sessions from few rats, so they are not independent.

• ✓ReproducedMain text, paragraph 6; Fig. 4, A and B

  Regression showed a consistent positive speed-rate relation in nearly all grid cells (141 of 150), head-direction cells (153 of 220) and conjunctive cells (45 of 53).

  Yet, regression analyses showed a consistent positive speed-rate relation in nearly all grid cells (141/150 cells, P G 0.001), headdirection cells (153/220 cells, P G 0.001) and grid ... head-direction cells (45/53 cells, P G 0.001), suggesting that a substantial proportion of the network expressed information about how fast the animal was moving (Fig. 4B).

  Main text, paragraph 6; Fig. 4, A and B

  The correlation of firing rate with running speed has a positive median in every cell type (0.28 to 0.58) against -0.06 for time-shifted spike trains, and 20% to 33% of cells in each type pass the 95th percentile of the shuffles where 5% are expected. Tested for each type as a population, not for each cell.