Large-scale brain networks account for sustained and transient activity during target detection

Area of Science:

• Cognitive Neuroscience
• Neuroimaging

Background:

• Target detection studies cognitive functions like attention and memory.
• The P300 component in EEG signals is linked to detecting task-relevant stimuli.
• Variability in P300 responses remains mechanistically unclear.

Purpose of the Study:

• Investigate if P300 variability relates to distinct cortical networks.
• Understand the contribution of large-scale brain networks to target detection.
• Explore the functional roles of attention networks in target detection.

Main Methods:

• Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) were used.
• 13 healthy subjects performed a visual oddball task.
• A trial-by-trial EEG-fMRI correlation approach was employed.

Main Results:

• Five large-scale brain networks were identified, overlapping with known attention, core, visual, and sensory-motor networks.
• The ventral attention network showed transient activation related to target occurrence.
• The dorsal attention network exhibited sustained activity, potentially for target search.

Conclusions:

• Distinct cortical networks, particularly the ventral and dorsal attention networks, play differential roles in target detection.
• The ventral attention network is involved in salient stimulus detection, while the dorsal network supports sustained target search.
• This research offers insights into the neural mechanisms underlying P300 variability during cognitive tasks.