Early Visual Cortex Supports One-Shot Episodic Memory via Spatially Tuned Reactivation.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neuroimaging

Background:

• Episodic memory retrieval often involves cortical reinstatement, reactivating perceptual representations in sensory cortex.
• Prior evidence for cortical reinstatement in sensory areas typically requires repeated exposure or explicit recall instructions.
• Everyday memory recall often occurs after single events without practice or instruction.

Purpose of the Study:

• To investigate if memory responses emerge in the early visual cortex after a single encoding event.
• To determine if the early visual cortex supports one-shot episodic memory retrieval.
• To link neural activity in early visual cortex to the precision of memory recall.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to scan 20 adults.
• Participants viewed objects presented once in parafoveal locations.
• Later, participants performed recognition and location recall tasks for the viewed objects.

Main Results:

• Low-amplitude responses were detected in the early visual cortex (V1-V3) during memory tasks.
• These responses were tuned to the original parafoveal location of the encoded objects.
• Neural tuning in early visual cortex correlated with successful memory recall and precision.

Conclusions:

• The early visual cortex exhibits memory-related responses even after a single exposure.
• Cortical reinstatement in early visual areas contributes to retrieving specific sensory details from single events.
• These findings highlight the role of early visual cortex in the fundamental capacity of episodic memory.