Watching violent movies for a long time can brutalize people, making them indifferent to cruelty.

brutalize 由词根 brutal（残忍的）加上动词后缀 -ize 构成，表示"使变得残忍"或"使麻木不仁"。这个词描述的是暴力内容对人性的负面影响，使人逐渐丧失对残忍行为的敏感度。