Excessive focus refers to an intense and overwhelming concentration on a particular subject or aspect, often to the point of neglecting other important areas.
Related terms
Perseveration: The tendency to get stuck on one idea or behavior and have difficulty shifting attention.
Obsession: An intrusive thought, urge, or image that repeatedly enters someone's mind causing anxiety or distress.
Tunnel vision: A metaphorical term for being hyper-focused on one thing while ignoring everything else around it.