DOI: 10.5061/dryad.xgxd254rb
title: Individual choices shape divergent brains and behaviors

description: Individual choices shape life course trajectories of brain structure and
 function beyond genes and environment. We hypothesized that individual
 task engagement in response to a learning program results in
 individualized learning biographies and connectomics. Genetically
 identical female mice living in one large shared enclosure freely engaged
 in self-paced, automatically administered and monitored learning tasks. We
 discovered growing and increasingly stable inter-individual differences in
 learning trajectories. Adult hippocampal neurogenesis and connectivity as
 assessed by a high-density multi-electrode array positively correlated
 with the variation in exploration and learning efficiency. During some
 tasks, divergence transiently collapsed, highlighting the sustained
 significance of context for individualization. Thus, equal environments
 and equal genes do not result in equal learning biographies because life
 confronts individuals with choices that lead to divergent paths.
description: This dataset contains behavioral data from a study examining how
 individual choices shape brain structure and function in mice, beyond
 genetic and environmental factors. Using the IntelliCage (IC) system, a
 fully automated home-cage apparatus from TSE Systems, we tracked the
 exploratory, learning, and social behaviors of 16 genetically identical
 female mice over two months. The apparatus is equipped with four operant
 conditioning corners, each of which contains two water bottles with
 sweetened water as reward, two nosepoke holes, and doors allowing or
 denying access to the reward. The system, controlled by software, allowed
 us to create specific learning protocols where access to rewards was based
 on predefined combinations of factors, such as corner visits, nosepoke
 patterns, and individual mouse identity. The IC system recorded events
 such as corner visits, nosepokes, and licking behavior through RFID
 antennas, nosepoke sensors, and lickometers. Mice engaged in 10
 self-paced, pre-programmed learning tasks, with each animal's
 behavior automatically recorded and time-stamped. The dataset includes raw
 event logs, detailing the time, duration, mouse ID, corner ID, and
 corresponding rewards for each behavioral event, providing a comprehensive
 look into individual learning trajectories. During the
 10-day adaptation phase, mice were familiarized with the enclosure,
 presence of rewards at the corners, the requirement to nosepoke for a
 reward, and the time restrictions on reward access. The learning phase
 consisted of five main tasks with ten variations: Place Learning with 3
 Correct Corners (PL3CC), Place Learning with 1 Correct Corner (PL1CC),
 Patrolling (with correct corners shifting either clockwise or
 anticlockwise), Reverse Patrolling (where the correct corner's
 direction was reversed), and the Serial Reversal Task, in which two
 diagonally opposite corners were rewarded and the assignment of correct
 corners was reversed every four days. Behavioral data was recorded
 automatically by the IntelliCage system, capturing detailed information
 about each mouse's visits to operant corners. Exploratory behavior
 during the adaptation phase was assessed through roaming entropy (RE).
 This metric was derived from the duration of visits to different corners
 and then converted into the probability of the mouse being located in a
 specific corner on a given day using Shannon entropy. In the learning
 phase, the percentage of correct visits was used to track learning, where
 a correct visit was defined as a visit to a rewarded corner followed by
 more than one nosepoke, indicating reward-seeking behavior. Flexibility in
 adapting to new tasks was assessed by calculating how often mice visited
 previously correct corners after a task reversal.