Cognitive variability in bipolar I disorder: A cluster-analytic approach informed by resting-state data

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Psychology

Background:

• Cognitive deficits are known in bipolar disorder I (BD-I), but specific affected abilities lack consensus.
• Phenotypic heterogeneity in BD-I suggests potential patient subgroups.
• Identifying these subgroups and their neural underpinnings is crucial.

Purpose of the Study:

• To identify distinct cognitive profiles within BD-I patients.
• To investigate underlying neuronal network differences associated with these profiles.
• To explain the heterogeneity of BD-I phenotypes.

Main Methods:

• 54 euthymic BD-I patients underwent cognitive testing and resting-state neuroimaging.
• Hierarchical cluster analysis was applied to executive function scores.
• Clusters were compared to healthy controls, and network properties were analyzed.

Main Results:

• Three distinct cognitive profiles emerged: cognitive flexibility/motor inhibition deficits (Cluster 1), impulsive decision-making (Cluster 2), and strong visuospatial planning (Cluster 3).
• Weaker interregional connections were observed in Cluster 1 compared to Cluster 2.
• Cluster 3 showed higher modularity, correlating with problem-solving and risk-taking.

Conclusions:

• Distinct cognitive profiles, not a uniform deficit, characterize BD-I patients.
• Interregional connectivity and subnetwork organization may underlie observed cognitive strengths and weaknesses.
• These findings contribute to understanding BD-I heterogeneity.