Does ventrolateral prefrontal cortex help in searching for the lost key? Evidence from an fNIRS study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Medical Imaging

Background:

• Spatial navigation planning is crucial for daily activities.
• Neuropsychological tests like the Key Search Task (KST) assess cognitive functions.
• Understanding the neural correlates of navigation planning is essential for clinical applications.

Purpose of the Study:

• To investigate the hemodynamic response in the prefrontal cortex during navigation planning using the KST.
• To identify specific brain regions involved in mental navigation and planning.
• To explore the utility of functional near-infrared spectroscopy (fNIRS) in studying navigation.

Main Methods:

• Thirty-eight healthy volunteers performed the KST and a control task.
• A twenty-channel functional near-infrared spectroscopy (fNIRS) system measured hemodynamic responses (O2Hb and HHb changes).
• Prefrontal cortex activity was analyzed during task execution.

Main Results:

• Activation was observed in the right ventrolateral prefrontal cortex (rVLPFC) during the KST (mental navigation).
• Bilateral dorsolateral prefrontal cortex (DLPFC) activation was noted during the control task.
• The findings localized the rVLPFC as a key region for mental navigation.

Conclusions:

• The rVLPFC plays a critical role in spatial navigation planning, as evidenced by its activation during the KST.
• The KST, combined with fNIRS, is a promising tool for evaluating navigation planning in clinical settings.
• fNIRS offers a less constrained neuroimaging method for studying human navigation.