38. Why Does Attention Fade Over Time? The Reticular Activating System, Vigilance Decrement and ADHD
MRCPsych on the Go: Revision EssentialsShow Notes
Why can a radar operator miss an obvious blip after two hours on shift, but catch it easily in the first ten minutes? The problem isn't their eyesight, it's how alertness itself behaves over time. We look at how the brain regulates arousal through the reticular activating system, why sustained attention reliably decays over time, the vigilance decrement, and how the same arousal circuits link to ADHD and to disturbed attention and awareness in delirium. A note before we start: the syllabus pa...
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