mental numbness or a lack of sensitivity and interest toward external changes or stimuli

面对时代的巨大变迁，他表现出一种思想顽钝的冷漠。

a state of being slow-witted, lacking mental sharpness, or having blunt thinking

长期的封闭生活使他变得思想顽钝，很难跟上大家的节奏。