Scene-selectivity in CA1/subicular complex: Multivoxel pattern analysis at 7T.

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Neuroimaging

Background:

• Univariate fMRI studies suggest the hippocampus's anteromedial subicular complex is key for scene cognition.
• Univariate methods may lack sensitivity for scene activity in other hippocampal subfields like CA1.
• Hippocampal functional gradients challenge traditional anatomical subfield boundaries for category selectivity.

Purpose of the Study:

• To investigate scene-based cognition across hippocampal subfields using multivariate pattern analysis.
• To determine if scene selectivity is confined to the anteromedial subicular complex or distributed more broadly.
• To compare the topographical organization of scene and face processing within the hippocampus.

Main Methods:

• Applied searchlight multivariate pattern analysis (MVPA) to high-resolution 7T fMRI data.
• Utilized a visual odd-one-out discrimination task with scene and non-scene stimuli (including faces).
• Examined overlap of scene-selective maps with hippocampal subfields and surrounding cortices.

Main Results:

• Scene-selective activity was found in the anteromedial subicular complex, inferior CA1, and posteromedial/parahippocampal cortices.
• Probabilistic maps showed gradients of scene category selectivity, strongest in the medial hippocampus.
• Face category selectivity showed stronger overlap in the lateral hippocampus, suggesting parallel processing streams.

Conclusions:

• Scene processing in the human hippocampus is more distributed than previously suggested by univariate approaches.
• Findings support parallel processing streams for scene and face information within the hippocampus and connected networks.
• This study refines our understanding of hippocampal networks involved in scene versus face perception.