Looking both ways through time: the Janus model of lateralized cognition

Area of Science:

• Neuroscience
• Evolutionary Psychology
• Cognitive Science

Background:

• Current models of brain laterality (hemispheric asymmetries) are limited in explaining overall patterns.
• A new approach is needed, focusing on shared contributions to adaptive hemispheric roles rather than intrahemispheric similarities.

Purpose of the Study:

• To propose the Janus model, an evolutionary framework for understanding brain laterality.
• To elucidate the distinct, complementary roles of the left and right hemispheres.

Main Methods:

• Literature review and theoretical modeling based on evolutionary considerations.
• Analysis of evidence from research on motor control and semantic priming.

Main Results:

• The Janus model posits the left hemisphere anticipates future scenarios and selects among them.
• The right hemisphere integrates ongoing information into a unified past view for novel event detection and response.

Conclusions:

• The Janus model offers a novel explanation for hemispheric asymmetries based on complementary evolutionary roles.
• This model contrasts with existing frequency-based models attempting to explain laterality broadly.