A psychologist is highlighting a counterintuitive habit that may slowly make a sharp mind feel less sharp: leaning too heavily on the skills, routines and patterns a person has already mastered. Rather than neglect or laziness, the concern is that deep competence can make daily thinking more automatic and less demanding over time.

The idea, based on new research referenced by Forbes, is that mental dullness may grow quietly when life becomes filled with tasks we can do almost effortlessly. When people spend most of their time operating inside familiar strengths, they may face fewer moments that require real problem-solving, adaptation or fresh learning.

That does not mean expertise is a bad thing. Building knowledge and skill is valuable, but the warning is about imbalance. If too much of everyday work and life runs on autopilot, the brain may get less of the challenge that helps keep thinking flexible and engaged.

The takeaway is that a sharp mind may depend not only on what a person knows, but also on whether they still make room for novelty, difficulty and growth. The habit to watch is not doing too little, but staying too comfortably inside what has already become easy.