Hypofrontal activity during word retrieval in older adults: A near-infrared spectroscopy study

► NIRS was sensitive to VFT-related supplementary motor area (SMA) activity. ► Elder SMA responses were different from young ones at the same VFT level. ► Anterior SMA in elder was less activated than that in younger. ► Anterior SMA response in elder only regresses with VFT performance. ► Anterior SMA in elder may be closely related to word retrieval difficulties.