Facing successfully high mental workload and stressors: An fMRI study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psychophysiology

Background:

• Understanding brain activity under stress and high cognitive load is crucial for mental state assessment.
• Previous research indicates distinct neural network responses to workload and stressors.

Purpose of the Study:

• To investigate brain activation patterns and autonomic responses during high mental workload with auditory stressors.
• To explore the interplay between the executive control network (ECN), salience network (SN), and default mode network (DMN) under stress.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to measure brain activity in 20 participants.
• Participants performed a complex cognitive task under safe and aversive (auditory stressor) conditions.
• Autonomic measures including heart rate and pupil diameter were recorded.

Main Results:

• Increased mental workload engaged the lateral frontoparietal ECN and disengaged DMN regions.
• Auditory stressors led to enhanced ECN activity and deactivations in limbic SN regions.
• Task performance was maintained under stress due to inhibition of auditory regions (superior temporal gyri).

Conclusions:

• The balance between ECN, SN, and DMN recruitment can serve as an objective measure of mental state.
• Increased lateral prefrontal activity indicates efficient mental effort, while medial prefrontal deactivation suggests overload or disengagement.