Operant social self-administration in male CD1 mice.

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Animal Models

Background:

• A model of operant social reward using female CD1 mice was previously established.
• This model involves lever pressing for affiliative social interaction with a same-sex peer.
• Male CD1 mice may exhibit lever pressing for aggressive interactions under certain conditions.

Purpose of the Study:

• To determine the generality of the operant social self-administration model to male CD1 mice.
• To investigate if male mice lever press for social interaction or aggression.
• To assess the influence of housing conditions and isolation on social behaviors in male mice.

Main Methods:

• Male CD1 mice were trained to lever press for food and social interaction under fixed-ratio schedules.
• Motivation for social interaction was tested after 15 days of isolation.
• The effects of housing conditions on operant social self-administration and unconditioned social interactions were evaluated.

Main Results:

• Male CD1 mice demonstrated operant social self-administration for peer interaction, independent of housing.
• Motivation to seek social interaction persisted after isolation.
• No sex differences in operant social self-administration or seeking were observed.
• Group-housed male mice did not exhibit aggression towards a peer.

Conclusions:

• The operant social self-administration model is generalizable to male CD1 mice.
• Adult, socially housed male CD1 mice can be utilized in operant social reward studies.
• The potential confound of aggressive responding is absent in this model for male mice.