Using fMR-adaptation to track complex object representations in perirhinal cortex.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Visual Perception

Background:

• The medial temporal lobe's role in memory is expanding beyond declarative memory.
• Perirhinal cortex is increasingly recognized for its function within the ventral visual stream.

Purpose of the Study:

• To investigate the role of the visual processing stream in perceptual binding.
• To determine if item feature binding occurs before hippocampal involvement.

Main Methods:

• Functional magnetic resonance adaptation (fMRa) was employed to measure brain activity.
• Blood-oxygen-level-dependent (BOLD) responses were compared between fused and non-fused object stimuli.

Main Results:

• Neural adaptation to fused objects, but not non-fused ones, was observed in the left fusiform cortex and left perirhinal cortex.
• This indicates these regions are involved in the perceptual binding of item representations.

Conclusions:

• The visual processing stream, including the left fusiform and perirhinal cortex, contributes to perceptual binding.
• Item feature binding in these visual areas precedes hippocampal binding mechanisms.