Integration Between Cerebral Hemispheres Contributes to Defense Mechanisms

Area of Science:

• Neuroscience
• Psychology
• Developmental Psychology

Background:

• Defense mechanisms are crucial for psychological coping.
• The neural basis of defense mechanism development remains largely unknown.
• Interhemispheric integration may play a role in mature defense mechanisms.

Purpose of the Study:

• To investigate the role of interhemispheric integration in defense mechanism development.
• To examine defense mechanism use in individuals with agenesis of the corpus callosum (AgCC).

Main Methods:

• Compared defense mechanism use in adults with AgCC (N=27) and matched healthy controls (N=30).
• Assessed defense mechanisms (denial, projection, identification) using Thematic Apperception Test narratives scored by the Defense Mechanism Manual.
• Analyzed defense mechanism maturity across developmental levels.

Main Results:

• Individuals with AgCC exhibited greater use of immature defense mechanisms (denial) and less use of mature mechanisms (identification) compared to controls.
• These differences were evident after age 18, suggesting a disruption in mature defense development.
• Findings characterize social and emotional processing in AgCC.

Conclusions:

• Functional integration across brain hemispheres is important for the development of defense mechanisms.
• AgCC is associated with altered defense mechanism profiles, highlighting the role of the corpus callosum.
• Results support the hypothesis linking interhemispheric integration to defense mechanism maturation.