Variable behavior and repeated learning in two mouse strains: Developmental and genetic contributions.

Area of Science:

• Neuroscience
• Behavioral Science
• Animal Models

Background:

• Behavioral inflexibility is often studied using reversal learning tasks.
• Limited research exists on reinforcement contingencies that select for high response variability in mice, especially in neurodevelopmental disorder models.

Purpose of the Study:

• To assess behavioral variability in BALB/c and C57Bl/6 mice using operant variability and incremental repeated acquisition (IRA) tasks.
• To investigate the impact of reinforcement contingencies on response variability.
• To evaluate BALB/c mice as a model for autism spectrum disorder (ASD) related to behavioral variation.

Main Methods:

• Operant variability task to measure response patterns under different reinforcement conditions.
• Incremental Repeated Acquisition (IRA) task to assess learning and performance sequences.
• Comparison of BALB/c and C57Bl/6 mouse strains.

Main Results:

• During adolescence, BALB/c mice showed more repetitive responses than C57Bl/6 mice when variability was not required, but more variable responses when it was.
• In adulthood, both strains learned an unchanging sequence equally well in the IRA task.
• BALB/c mice significantly outperformed C57Bl/6 mice when novel and established learning sequences alternated.
• Adolescent experience with variability did not influence adult IRA task performance.

Conclusions:

• BALB/c mice exhibit high sensitivity to reinforcement contingencies and are fast, robust learners.
• The findings suggest limitations in using BALB/c mice as a sole model for all ASD-related behavioral deficits, particularly those involving response variation.
• This study highlights unique aspects of behavioral variability and learning in different mouse strains.