A generalized cortical activity pattern at internally generated mental context boundaries during unguided narrative...

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• Human experience is segmented into events based on sensory prediction errors, marked by neural responses at event boundaries.
• Internal mental states can also transition, creating boundaries without external input changes, raising questions about shared neural mechanisms.

Purpose of the Study:

• To investigate whether transitions between internal mental contexts share neural response properties with externally driven event boundaries.
• To explore the neural correlates of internally generated boundaries during unguided thought processes.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed.
• Participants watched short movies and then verbally recalled them in a self-selected order.
• Neural activity was analyzed during transitions between recalled movies, representing internal boundaries.

Main Results:

• Stereotyped spatial activation patterns were observed in the default mode network, particularly the posterior medial cortex, following the offset of each recalled movie.
• These default mode network patterns were consistent across different movie contents and tasks (watching vs. recall).
• Crucially, the neural patterns at internal boundaries between movies differed significantly from those at event boundaries within movies.

Conclusions:

• Major transitions between internal mental contexts elicit distinct neural phenomena.
• These phenomena are shared across internal and external modes of boundary detection.
• The findings suggest a unique cognitive state associated with the reconfiguration of situation models during mental context shifts.