General intelligence is associated with working memory-related brain activity: new evidence from a large sample study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psychometrics

Background:

• Psychometric intelligence and working memory capacity are known to be closely related.
• Previous studies investigating neural correlates of intelligence and working memory have faced statistical limitations.
• Understanding the neural basis of cognitive abilities is crucial for cognitive neuroscience.

Purpose of the Study:

• To examine the association between neural activation patterns during the N-back task and psychometric intelligence.
• To investigate the relationship between brain activity, working memory performance, and cognitive ability.
• To address statistical limitations of prior research in this domain.

Main Methods:

• Utilized a large cohort of 1235 young adults.
• Employed robust voxel-by-voxel permutation-based statistics at the whole-brain level.
• Analyzed neural activation during the N-back working memory paradigm.

Main Results:

• Observed significant correlations between neural activity and cognitive ability, often in peripheral brain areas or network boundaries.
• Found that lower activity in the task-positive network (TPN) and less task-induced deactivation (TID) in the task-negative network (TNN) were associated with higher cognitive ability.
• Identified a unique role for the pre-supplementary motor area, showing greater working memory-related activity in intelligent subjects.

Conclusions:

• Greater cognitive ability is associated with a lower overall brain response to cognitive demand, challenging some aspects of the neural efficiency theory.
• Findings suggest that the expansion or modulation of the TPN and TNN relates to cognitive ability.
• The pre-supplementary motor area demonstrates a distinct pattern of activation, highlighting its specific role in cognitive control and working memory for intelligent individuals.