DOI: 10.5061/dryad.k98sf7mm6
title: Data from: View invariant representations in ancestral cortex

description: A multilayered, thalamo-recipient visual cortex emerged ~320 MYA in stem
 amniotes. Despite its importance for understanding the evolution of
 cortical computation, its function remains unknown. We recorded visually
 evoked responses in the dorsal cortex of behaving turtles, considered a
 mammalian neocortex homolog. Using a spatial oddball paradigm, we found
 tuning to stimuli in deviant positions alongside adaptation to standard
 positions within the visual field. Eye tracking demonstrated that
 responses remained spatially selective despite gaze shifts altering
 retinal stimulus position. Thus, the turtle cortex encodes unexpected
 visual stimuli using computations invariant to retinal position, a
 property previously observed only in higher mammalian cortices. These
 results indicate that invariance computations preceded the evolution of
 local filtering computations in mammalian primary cortices, pointing to a
 new function for ancestral cortices. They also challenge hierarchical
 models of invariance computations, which assume that invariance is built
 from low-level features across multiple processing steps.
description: ## **Title of dataset:** ## View invariant representations in ancestral
 cortex Access this dataset on Dryad. DOI:
 [10.5061/dryad.k98sf7mm6](https://doi.org/10.5061/dryad.k98sf7mm6) ##
 Description of the data and file structure: Code for reproducing figures
 for Becker et al, "View invariant representations in ancestral
 cortex" The pre-processed electrophysiological data, as well as head
 and eye angles of the experimental animals, are included to reproduce the
 specific data shown in our publication. The code provided loads the data
 and creates the subplots of the figures, visualizing and explaining the
 data provided. The code is supposed to be run in Matlab 2024b, no further
 packages are necessary. Each Figure/subfigure has a script and
 corresponding metadata that will be loaded in the script. It is
 recommended to download all files into a folder and make it the current
 directory in matlab. Then each script can be opened, and the metadata will
 automatically be loaded from the same folder. Running each script will
 give one or several figure outputs in the end. The name of the script
 indicates which figure from the publication it refers to, e.g.
 “plot_Fig1g.m” will load the data and recreate the figure 1g. If a piece
 of code reproduces several figures from the same data it is indicated in
 the filename divided by underscores (e.g. “plot_Fig1i_j.m” plots figure 1i
 as well as 1j). The names of the data files for each code are mentioned
 and loaded in the beginning of each script. The content and structure of
 the data files vary from figure to figure but is explained inside the code
 and by the figure outputs. The main variables of the data are: LFP –
 downsampled electrophysiological data for specified periods PC1 – first
 principal component of the LFP data nPC1 – z-scored mean PC1 per recording
 session Headangles/eyeangles – the estimated head and eye angles of the
 animal viewangle - combined head+eye angles of the animal
 Headspeed/eyespeed – the estimated speeds of the head and the eye of the
 animal recname – the individual identifier per session #### Sharing/Access
 information Future code updates and packages can be found at:
 [https://github.com/EvolutionaryNeuralCodingLab/SpatiallySelectiveViewInvariance](https://github.com/EvolutionaryNeuralCodingLab/SpatiallySelectiveViewInvariance)