Neural changes associated with semantic processing in healthy aging despite intact behavioral performance

• Published in: Brain and language Vol. 149; pp. 118 - 127
• Main Authors: Lacombe, Jacinthe, Jolicoeur, Pierre, Grimault, Stephan, Pineault, Jessica, Joubert, Sven
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.10.2015
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Aging - physiology; Elderly; Female; Healthy Volunteers; Humans; Language; Magnetoencephalography; Male; MEG; Memory - physiology; Middle Aged; Nerve Net - physiology; Neural reorganization; Normal aging; Parietal Lobe - physiology; Prefrontal Cortex - physiology; Semantic executive processes; Semantic memory; Semantics; Temporal Lobe - physiology; Thinking - physiology; Young Adult; Semantic memory; Language; Normal aging; Semantic executive processes; Elderly; MEG; Neural reorganization
• ISSN: 0093-934X; 1090-2155
• DOI: 10.1016/j.bandl.2015.07.003

•Neuronal changes underlying semantic processing occur during the course of aging.•Young (vs old) adults recruit the inferior prefrontal regions to a greater extent.•Older (vs younger) adults recruit the temporoparietal region to a greater extent.•This may contribute to maintain a high-level performance during semantic processing. Semantic memory recruits an extensive neural network including the left inferior prefrontal cortex (IPC) and the left temporoparietal region, which are involved in semantic control processes, as well as the anterior temporal lobe region (ATL) which is considered to be involved in processing semantic information at a central level. However, little is known about the underlying neuronal integrity of the semantic network in normal aging. Young and older healthy adults carried out a semantic judgment task while their cortical activity was recorded using magnetoencephalography (MEG). Despite equivalent behavioral performance, young adults activated the left IPC to a greater extent than older adults, while the latter group recruited the temporoparietal region bilaterally and the left ATL to a greater extent than younger adults. Results indicate that significant neuronal changes occur in normal aging, mainly in regions underlying semantic control processes, despite an apparent stability in performance at the behavioral level.