Age-related differences in functional connectivity during scene encoding

• Main Author: Leow, Dayton Wei Yang
• Other Authors: Chen Shen-Hsing Annabel
• Format: Student Research Poster
• Language: English
• Published: 2014
• Subjects: Relational encoding; Scenes
• Online Access: https://hdl.handle.net/10356/79544; http://hdl.handle.net/10220/24239
• Institution: Nanyang Technological University

The functional network underlying episodic encoding involves both the prefrontal cortex (PFC) and medial temporal lobe (MTL).1 Episodic encoding differs in terms of the stimuli and the types of encoding.2. Past neuroimaging studies have found both the parahippocampus in the MTL and inferior frontal gyrus (IFG) in the PFC to be activated for scene encoding.3 In addition, when scenes are encoded based on its meaningfulness (i.e. relational encoding), the hippocampus will be activated for relational binding of the stimuli.4. In general, there is converging support for both the IFG and MTL (hippocampus/parahippocampus) to be functionally connected and work in tandem during relational encoding of scenes. Older adults performing relational encoding5 and scene encoding3 exhibited increased inferior frontal activation than young adults to meet their increased cognitive demand. Specifically, an increased inferior frontal activity was shown to compensate for the decreased medial temporal activity.3. The posterior-to-anterior shift in aging (PASA) model6 could potentially be used to account for this medial temporal-to-inferior frontal compensatory shift in brain activation. Although past studies have examined age-related differences in both the IFG and MTL activation during relational encoding of scenes, the IFG-MTL co-activation is not specifically investigated. Hence, this study utilized a functional MRI (fMRI) task sensitive to relational encoding of scenes to evaluate age-related differences in the IFG-MTL functional connectivity (FC). [1st Award]