Paw preferences in mice and rats: Meta-analysis

Area of Science:

• Neuroscience
• Animal Behavior
• Comparative Psychology

Background:

• Mice and rats are crucial animal models in neuroscience research.
• Understanding brain-behaviour relationships, especially hemispheric asymmetries, is vital but often hindered by small sample sizes in rodent studies.
• Paw preference is a key indicator of behavioral lateralization.

Purpose of the Study:

• To statistically integrate existing data on paw preferences in rats and mice using meta-analysis.
• To investigate the presence and significance of individual and population-level hemispheric asymmetries in these species.
• To clarify conflicting findings regarding rodent brain-behaviour relationships.

Main Methods:

• A meta-analysis approach was employed to synthesize data from multiple studies on rodent paw preference.
• Statistical integration of findings on paw preferences in mice and rats was performed.
• Individual and population-level asymmetries were assessed.

Main Results:

• Significant individual hemispheric asymmetries were detected in both mice (81% preference) and rats (84% preference).
• Contrary to human studies, no population-level asymmetries in paw preference were found in either species.
• The findings highlight the importance of considering individual differences in hemispheric specialization.

Conclusions:

• Individual-level hemispheric differences in paw preference are prevalent in mice and rats.
• Population-level brain-behaviour asymmetries, as seen in humans, were not evident in the analyzed rodent data.
• Recognizing individual hemispheric variations is critical for both basic and clinical neuroscience research involving rodents.