Episodic Memory Encoding and Retrieval in Face-Name Paired Paradigm: An fNIRS Study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Medical Imaging

Background:

• Episodic memory (EM) is crucial for cognitive function and is vulnerable to aging and pathology.
• The paired-associate learning (PAL) paradigm is a standard method for assessing EM.
• Investigating non-invasive neuroimaging techniques like functional near-infrared spectroscopy (fNIRS) for EM assessment is valuable.

Purpose of the Study:

• To determine if fNIRS can detect cortical activity during the encoding and retrieval phases of the PAL paradigm.
• To examine how task novelty and difficulty influence cortical activity during memory tasks.
• To explore the potential of fNIRS for clinical EM assessments.

Main Methods:

• Twenty-two male college students participated in a face-name PAL task.
• 40-channel fNIRS was used to measure cortical activity across fronto-parietal and middle occipital regions.
• Task parameters including novelty and difficulty were manipulated.

Main Results:

• fNIRS detected distinct patterns of cortical activity for encoding (bilateral frontal cortex) and retrieval (left orbitofrontal cortex).
• Increased HbO in superior parietal and decreased HbO in inferior parietal regions were observed during encoding.
• Higher task difficulty correlated with increased bilateral prefrontal cortex activity, while novelty correlated with occipital activation.

Conclusions:

• The combination of PAL and fNIRS effectively differentiates neural activity associated with memory encoding and retrieval.
• fNIRS demonstrates potential as a tool for evaluating episodic memory in clinical settings.
• Task characteristics like difficulty and novelty modulate specific brain regions during memory processing.