Positive Interpretation of Emotional Ambiguity Across Development: LC-dlPFC Circuitry

Area of Science:

• Neuroscience
• Developmental Psychology
• Cognitive Science

Background:

• Emotionally ambiguous facial expressions are crucial for understanding how the brain makes judgments under uncertainty.
• Developmental changes in interpreting emotional ambiguity are not well understood at the neural level.

Purpose of the Study:

• To investigate how locus coeruleus (LC) circuitry and its connectivity with the prefrontal cortex change across development.
• To examine the relationship between neural activity, decision-making processes, and interpretive bias in emotional ambiguity resolution.

Main Methods:

• fMRI scans were conducted on participants aged from late childhood to middle adulthood during an emotional facial morph task.
• Behavioral data were analyzed using signal detection theory and drift-diffusion modeling.
• Neural data were analyzed using LC-seeded generalized psychophysiological interaction and trial-level neural models.

Main Results:

• A positive interpretive bias increased with age, primarily driven by changes in the drift intercept (evaluative evidence accumulation).
• Locus coeruleus-dorsolateral prefrontal cortex (LC-dlPFC) coupling was associated with positive bias, particularly in middle-aged adults.
• LC's contribution to bias involved slower temporal dynamics, while dlPFC provided a clearer moment-to-moment evaluative signal.

Conclusions:

• Age-related differences in interpreting emotional ambiguity are linked to variations in evaluative evidence accumulation within the LC-dlPFC circuitry.
• Evaluative drift bias represents a circuit-level mechanism underlying age-graded emotional ambiguity resolution.
• This study highlights the role of LC-prefrontal connectivity in processing emotional ambiguity across the lifespan.