The following text is about neuroscience.
The default mode network (DMN), a set of brain regions active when people are not focused on external tasks, was long considered mere "noise" in brain imaging. Researchers now understand it supports crucial functions: self-reflection, social cognition, remembering the past, and imagining the future. Dysfunction in the DMN appears in depression, autism, and Alzheimer's disease. The discovery challenges the assumption that rest is mental inactivity; instead, the resting brain engages in sophisticated internal processing that may be as important as task-focused cognition for mental health and function.
What shift in understanding does DMN research represent?
From viewing mental rest as sophisticated processing to viewing it as noise
From dismissing resting brain activity as noise to recognizing its important functions
From studying mental disorders to ignoring them
From focusing on internal processing to only studying external tasks
Correct Answer: B
Choice B is the correct answer. The DMN "was long considered mere 'noise'" but researchers now understand it "supports crucial functions"—a shift from dismissal to recognition.
- Evidence: Once noise; now understood as crucial.
- Reasoning: Assumptions about rest being inactivity were wrong.
- Conclusion: Resting brain activity is now valued.
Choice A is incorrect because this reverses the actual shift. Choice C is incorrect because disorders are now linked to DMN, not ignored. Choice D is incorrect because internal processing is now recognized as important.