Identification of cognitive load-dependent activation patterns using working memory task-based fMRI at various levels...

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Neuroimaging

Background:

• Working memory is crucial for daily functioning and cognitive processes.
• The N-back task is a standard method for assessing working memory capacity.
• Understanding brain activity during working memory tasks is key to diagnosing cognitive dysfunction.

Purpose of the Study:

• To investigate brain activity patterns in healthy individuals performing a visual N-back task with varying cognitive loads.
• To identify how increasing task difficulty affects brain activation and deactivation.
• To establish a baseline for comparing brain activity in individuals with cognitive impairments.

Main Methods:

• Functional magnetic resonance imaging (fMRI) data were collected from healthy, right-handed adults.
• Participants completed a Persian version of the visual N-back task at 1, 2, and 3-back difficulty levels.
• Statistical Parametric Mapping (SPM12) software was used for fMRI data analysis to detect cognitive load-dependent activation.

Main Results:

• Increased cognitive complexity led to more significant activation clusters in the cerebellum, frontoparietal lobes, insula, SMA, and lenticular nucleus.
• Deactivation patterns were observed in default mode network (DMN) regions during N-back task performance compared to a baseline.
• Activation patterns correlated with task difficulty, supporting the role of these brain regions in working memory.

Conclusions:

• The findings confirm the involvement of specific cortical and subcortical areas in working memory as assessed by the N-back task.
• Altered brain activation patterns with increasing task difficulty can serve as a biomarker for cognitive dysfunction.
• This research provides a foundation for future studies comparing healthy controls to patients with neurological diseases like Alzheimer's and MS.