Category specificity in the medial temporal lobe: A systematic review

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• The medial temporal lobe (MTL) comprises several subregions, including the perirhinal cortex, entorhinal cortex, parahippocampal cortex, and hippocampus.
• Theoretical accounts propose functional specialization within MTL subregions for processing different stimulus categories, but empirical evidence remains mixed.

Purpose of the Study:

• To systematically review and synthesize evidence for regional specialization within the MTL concerning the processing of faces, objects, and scenes.
• To evaluate neuroimaging and neuropsychological data to clarify the functional organization of MTL subregions.

Main Methods:

• Systematic review of univariate and multivariate neuroimaging studies.
• Analysis of neuropsychological studies involving patients with MTL lesions.
• Synthesis of findings across different methodologies to assess category specificity.

Main Results:

• Neuroimaging indicates preferential activation for faces in the perirhinal cortex, entorhinal cortex, and anterior hippocampus.
• Scene processing engages the parahippocampal cortex and hippocampus (anterior and posterior regions).
• Object representation shows some overlap with face and scene processing in anterior and posterior MTL regions, respectively.

Conclusions:

• Evidence supports regional specialization within the MTL for processing distinct visual categories like faces and scenes.
• Neuropsychological data highlight the hippocampus's crucial role in scene memory and perception, with less impact on face recognition if the perirhinal cortex is intact.
• Understanding category-specific patterns in the MTL is vital for refining theoretical models of MTL function.