Fig. 1: Identification of PCs in the larval zebrafish brain.
From: A population code for spatial representation in the zebrafish telencephalon
a, Rectangular behavioural arena with two landmark cues containing different visual patterns on opposing corners. There is a transparent inner polydimethylsiloxane (PDMS) wall (1.5 mm wide) preventing the animal from directly contacting the landmarks. b, Normalized median chamber occupancy across seven animals. c, Distribution of PF COM for all PCs with a confined PF in an example fish (Methods). Each dot represents the COM of one cell’s PF (Methods). The six example cells (coloured dots) are shown in d. d, Spatial activity maps (left, averaged neural response by location; Methods) and corresponding animal trajectories (right, colour coded by neural activity) are shown for six example cells from c. e, Responses of an example cell with a non-directional PF for two orientations of traversal (leftwards and rightwards) through the PF. Traversals across the 90 min experiment are colour coded by neural activity. Orientation is classified by the animal’s heading as it enters the PF. f, Anatomical distribution of PCs across seven animals plotted on the reference brain (maximum projection; Methods). g, Fraction of all PCs identified anywhere in the brain that are found in each brain region. Each animal is shown individually (orange dots, n = 7 animals), along with the median across animals (black lines). Anatomical subdivisions of the telencephalon (pallium and dorsal subpallium; Extended Data Fig. 2b) are plotted separately. h, Comparison of spatial specificity for PCs found in the telencephalon and for those found in the mesencephalon and rhombencephalon (n = 7 animals, P = 8.4 × 10−124, one-sided Mann–Whitney U-test). i, Spatial activity maps and animal trajectories for two example mesencephalic cells with significant spatial information encoding the interior (top) and periphery of the chamber (bottom). Scale bars, 10 mm (a–e,i), 50 µm (f). a.u., arbitrary units. di., diencephalon; mes., mesencephalon; rhomb., rhombencephalon; tel., telencephalon.
