Brain activation patterns in patients with post-stroke cognitive impairment during working memory task: a functional...

Area of Science:

• Neuroscience
• Cognitive Neurology
• Medical Imaging

Background:

• Stroke is a leading cause of long-term disability, often resulting in cognitive impairment.
• Working memory deficits are common following stroke and impact daily functioning.
• Understanding the neural underpinnings of post-stroke cognitive impairment is crucial for developing targeted interventions.

Purpose of the Study:

• To investigate frontal cortex activation patterns in patients with post-stroke cognitive impairment during working memory tasks.
• To compare brain activity between patients with and without cognitive impairment post-stroke and healthy controls.
• To identify neural correlates of cognitive deficits in the post-stroke population.

Main Methods:

• Utilized near-infrared spectroscopy (NIRS) to measure frontal cortex activation.
• Employed an immediate recall task to assess working memory performance.
• Included three groups: post-stroke cognitive impairment (n=15), post-stroke without cognitive impairment (n=17), and healthy controls (n=15).

Main Results:

• Healthy controls outperformed both post-stroke groups in the recall task.
• Left frontal lobe activation was dominant in healthy controls during the task.
• Post-stroke patients exhibited reduced left frontal activation and increased right frontal activation, particularly in frontopolar and orbitofrontal areas, with greater changes in the cognitively impaired group.

Conclusions:

• Post-stroke cognitive impairment is associated with reduced left prefrontal cortex activation during working memory tasks.
• Patients with post-stroke cognitive impairment utilize compensatory activation in the right prefrontal cortex (frontopolar and orbitofrontal regions).
• These findings highlight altered neural processing in working memory following stroke and suggest potential targets for rehabilitation.