Structural and functional alterations within the Papez circuit in subacute stroke patients

Area of Science:

• Neuroscience
• Neurology
• Cognitive Science

Background:

• Stroke frequently leads to cognitive impairment by disrupting brain networks.
• The specific impact on cognition-related neural circuits, like the Papez circuit, remains unclear.
• Understanding these early changes is crucial for addressing vascular cognitive impairment.

Purpose of the Study:

• To investigate structural and functional connectivity changes in the Papez circuit post-stroke.
• To explore the relationship between these neural alterations and cognitive function.
• To identify potential mechanisms and therapeutic targets for post-stroke cognitive deficits.

Main Methods:

• Studied 45 subacute stroke patients and 34 healthy controls.
• Measured gray matter volume within the Papez circuit structures.
• Utilized Granger causality analysis to assess directed functional connectivity from the hippocampus.

Main Results:

• Stroke patients showed significant gray matter atrophy in Papez circuit regions (hippocampus, amygdala, thalamus, anterior cingulate gyrus).
• Alterations in directed functional connectivity were observed within the Papez circuit, particularly involving the hippocampus and cingulate gyrus.
• These neural changes correlated with cognitive function in stroke survivors.

Conclusions:

• Early stroke disrupts both the structure and directed functional connectivity of the Papez circuit.
• These disruptions are associated with cognitive impairment in the subacute phase.
• Findings highlight the Papez circuit as a key area for understanding and potentially treating vascular cognitive impairment.