Hemispheric asymmetries in the amygdala: A comparative primer

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Comparative Psychology

Background:

• The amygdala is crucial for emotion processing in vertebrate brains.
• Left and right amygdala exhibit functional and structural differences (hemispheric asymmetries).
• Existing literature lacks a systematic integration of amygdala asymmetry findings.

Purpose of the Study:

• To provide an integrated overview of structural, functional, and connectivity findings on amygdala asymmetries.
• To explore how temporal, valence, and perceptual factors influence amygdala lateralization.
• To examine alterations in amygdala asymmetries in patient groups and offer interpretive guidelines for researchers.

Main Methods:

• Systematic literature review of basic and clinical findings on amygdala asymmetries.
• Integration of neuroimaging and comparative animal studies.
• Analysis of factors influencing functional lateralization and alterations in patient populations.

Main Results:

• Functional amygdala lateralization is influenced by temporal characteristics, emotional valence, and perceptual properties.
• Significant structural and functional asymmetries exist between the left and right amygdala.
• Alterations in amygdala asymmetries are observed in various patient groups.

Conclusions:

• Understanding amygdala asymmetries is key to interpreting neuroimaging and clinical findings.
• A comprehensive overview of amygdala lateralization aids researchers in cognitive and clinical neuroscience.
• This review provides a framework for interpreting atypical amygdala asymmetries and their clinical relevance.