Beyond the cortex-integrating hippocampal function into the Social Brain Hypothesis to explain advanced cognition

Area of Science:

• Neuroscience
• Evolutionary Biology
• Comparative Psychology

Background:

• The Social Brain Hypothesis (SBH) posits a link between primate brain size and social complexity.
• Empirical evidence for the SBH is limited, particularly regarding non-cortical brain regions.
• Existing models often focus on cortical expansion, potentially overlooking other crucial brain structures.

Purpose of the Study:

• To propose an expanded Social Brain Hypothesis (SBH) incorporating hippocampal functions.
• To investigate how both social and ecological pressures contribute to the emergence of cognition.
• To offer a more comprehensive framework for understanding primate brain evolution and cognitive origins.

Main Methods:

• Comparative analysis of brain structures and functions across primate species.
• Integration of data on social behavior, ecological factors, and hippocampal morphology/physiology.
• Development of a theoretical framework extending beyond cortical-centric models.

Main Results:

• The hippocampus plays a significant role in processing both social and ecological information.
• Cognitive abilities, including memory and spatial navigation, are shaped by a combination of social and environmental demands.
• An expanded SBH provides a more nuanced explanation for brain evolution than models focusing solely on social complexity.

Conclusions:

• Incorporating hippocampal functions offers a more complete understanding of brain evolution.
• Cognition is a product of interacting social and ecological pressures, not solely social ones.
• This extended framework is crucial for understanding the evolution of complex human cognitive abilities, such as language.