Multivoxel Pattern Analysis Reveals 3D Place Information in the Human Hippocampus

Area of Science:

• Neuroscience
• Cognitive Science
• Spatial Navigation

Background:

• Neuroscientific studies typically focus on 2D spatial navigation, leaving a gap in understanding 3D spatial representation in the brain.
• It is unknown if the brain encodes horizontal and vertical spatial information similarly or differently.

Purpose of the Study:

• To investigate how the brain represents 3D spatial information, specifically examining the encoding of horizontal and vertical movement.
• To determine if neural structures encode location and heading direction information differently across dimensions.

Main Methods:

• Used functional magnetic resonance imaging (fMRI) while participants navigated a virtual 3D environment.
• Applied multivoxel pattern analysis to analyze brain activity patterns related to spatial location and heading direction.

Main Results:

• The right anterior hippocampus showed isotropic 3D place encoding, sensitive to both horizontal and vertical location changes.
• Heading direction information was found in the right retrosplenial cortex and posterior hippocampus, primarily sensitive to vertical pitch.

Conclusions:

• The hippocampus plays a role in encoding 3D spatial locations, integrating both horizontal and vertical information.
• The retrosplenial cortex and posterior hippocampus prioritize vertical information for heading direction, potentially due to gravity cues.