无尽的刷屏，正在对你的大脑做什么？
过度消费网络内容的代价，远不只是浪费时间。它可能形成一个令人上瘾的神经化学循环，而你的手机恰好非常擅长让你困在其中。
Your Brain on Doomscroll
What Excessive Content Consumption Is Doing to You. Excessive content consumption is not just a bad habit. It is an additive neurochemical loop, and your phone is very good at keeping you in it.
2024年，牛津大学出版社将“brain rot”（大脑腐烂）评为年度词汇。这个词用来形容因过度接触低质量网络内容而产生的精神状态恶化，其使用频率在短短一年内激增了230%。但这个数字衡量的并不只是“分心”。它描述的是一种许多人已经隐约感受到、却很难准确说出来的变化：我们的专注力、动力，以及静下心来完成一个完整思考的能力，正在一点一点被侵蚀。
多巴胺并不只是所谓的“快乐物质”。它更准确地说，是一种与期待和动机有关的神经化学物质。大脑会在预期获得奖励时释放多巴胺，而不只是等到真正获得奖励之后才释放。
这也解释了为什么刷屏很难真正让人满足——下一条内容永远可能比上一条更有吸引力。
信息流中每一条引人入胜的帖子、令人意外的图片，甚至一场激烈的争论，都可能带来一次短暂的多巴胺反应。
这种奖励机制与暴饮暴食、冲动购物以及尼古丁依赖背后的机制存在相似之处。刷屏之所以特别容易让人陷入其中，是因为它几乎没有任何“摩擦成本”：你不需要付出太多努力，也不需要掌握什么技能，更几乎不需要等待——产生欲望与获得下一次刺激之间，只有一次滑动的距离。
当你终于放下手机，多巴胺相关的奖励信号随之降低。经历了几个小时高频、快速的刺激后，大脑会感受到这种落差，并产生重新拿起手机的冲动。
这并不意味着你“意志力太差”。这更像是大脑在适应环境之后产生的神经化学反应。真正的问题在于：这种机制并不是为了应对一台随时放在手边、可以无限提供刺激的设备而设计的。
刷屏就像是大脑的“廉价糖果”。它毫不费力、即时满足，却无法真正提供持久的滋养，只会让你在满足之后继续渴望更多。
大脑会通过不断调整自身的基线状态，来适应反复出现的刺激。当你频繁接触高刺激、低投入的内容时，大脑可能逐渐提高获得满足感所需要的刺激阈值。于是，那些过去能够让你感到愉快的活动，开始显得更加费力，也不再那么有吸引力。这就是神经适应。好消息是，这种适应并非不可逆。但它需要你有意识地改变自己持续接触的刺激类型。
持续、大量地刷屏，与注意力维持时间缩短、工作记忆表现下降，以及更难延迟满足等现象有关。
但这些变化并不意味着大脑已经“坏掉”。大脑具有很强的可塑性，能够根据新的输入不断调整和重组。只是这种重新适应，需要你持续接触那些比社交媒体信息流更需要耐心、思考和主动参与的活动。
此外，社交比较、容易引发焦虑的内容，以及碎片化的信息，都可能激活身体的应激通路。长期处于低水平的应激激活状态，尤其是在青少年群体中，与更高的焦虑和抑郁发生率有关。
社交媒体并不一定是问题的根源，但它可以成为一个非常高效的放大器。
你不需要因此彻底戒掉手机。真正需要改变的，是增加刷屏的摩擦、重新分配注意力，并让大脑重新获得更加持久的奖励来源。
- 为屏幕时间设定明确上限。把被动刷屏时间限制在每天30至60分钟，并像安排会议一样，有意识地安排这段时间。不要让刷屏成为你无聊时下意识填补空白的默认选择。这样，你重新掌握的就不只是屏幕时间，而是注意力的主动权。
- 主动选择算法给你看的内容。关注那些真正需要你参与、能够带来知识或自我成长的内容。对于那些持续制造焦虑、比较心理或愤怒，却没有提供实际价值的信息来源，可以选择取消关注、屏蔽或静音。你无法完全控制算法，但可以逐渐影响算法学会向你展示什么。
- 用更有挑战性的活动替代无脑刷屏。阅读、写作、解谜，或者学习一项新技能，都需要持续投入注意力。这些活动带来的满足感可能更慢，却往往更加持久。更重要的是，它们能够帮助你重新训练那种被碎片化内容不断打断的能力：长时间专注于一件事情。
- 保持身体活跃。身体活动能够促进脑源性神经营养因子（BDNF）的产生，而BDNF与神经可塑性和认知功能有关。即使只是每天散步30分钟，也可能对注意力和情绪产生可测量的积极影响。你不需要进行高强度运动，才能从中受益。
- 重视面对面的真实连接。面对面的互动能够更充分地调动社会奖赏系统。与此同时，你还需要观察非语言信号、理解对话节奏，以及应对交流中的不确定性。这些过程都需要大脑持续处理复杂的社会信息，也会调动前额叶皮质等脑区参与。而这些能力，并不是简单地刷评论区就能够得到同样的锻炼。
- 必要时，寻求专业帮助。如果屏幕使用已经造成明显困扰、影响睡眠，或者伴随着持续性的焦虑或抑郁症状，那么寻求合资格专业人士的帮助，会是更合适的下一步。针对问题性科技使用和相关强迫行为的行为干预，也已经显示出一定的效果。
“大脑腐烂”并不是一个精确的科学术语，但它指向的问题却相当真实。大脑不会真的“腐烂”，它会适应。而当大脑长期适应廉价、即时、毫不费力的刺激时，那些需要耐心、深度和持续投入的活动，就可能开始让人觉得格外困难。
但改变并不需要轰轰烈烈。出路是渐进的。每一次你选择放下手机，转而去做一件需要更多注意力、更深思考或更多耐心的事情，都是在向大脑发出新的信号。因为大脑的适应是双向的。
重新找回专注力，并不只是意志力或自律的问题。更重要的是：你每天反复要求自己的大脑关注什么。所以，从小处开始，从今天开始。你重新获得的清晰感，并不是一次性的奖励。它更像是一种大脑本来就拥有的状态——当你不再不断打断自己的注意力，它便能够慢慢回到那里。
参考文献
- Meshi D, Tamir DI, Heekeren HR. The emerging neuroscience of social media. Trends in Cognitive Sciences. 2015;19(12):771–782.
- Turel O, He Q, Xue G, Xiao L, Bechara A. Examination of neural systems sub-serving Facebook “addiction”. Psychological Reports. 2014;115(3):675–695.
- Shensa A, Escobar-Viera CG, Sidani JE, et al. Problematic social media use and depressive symptoms among U.S. young adults. Social Science & Medicine. 2017;182:150–157.
- Andrews S, Ellis DA, Shaw H, Piwek L. Beyond self-report: tools to compare estimated and real-world smartphone use. PLOS ONE. 2015;10(10):e0139004.
冯丽君 Zoey Fong 是科学传播者与内容策略师，帮助生物科技及医疗健康领域的团队，将复杂的生物医学研究转化为清晰、有影响力的策略性内容。新加坡 · 7年以上生物医学科学经验 · 8+篇论文发表 · PMP认证。
Oxford University Press named ‘brain rot’ its 2024 Word of the Year. The term, which refers to the mental deterioration attributed to excessive consumption of low-quality online content, had surged 230% in usage over 12 months. That number does not measure distraction. It measures something most people already feel but struggle to name: the slow erosion of attention, motivation, and the ability to sit with a thought long enough to finish it.
Dopamine is not a pleasure chemical. It is an anticipation chemical. The brain releases it in response to the expectation of a reward, not the reward itself. This is why the scroll never satisfies, and the next post is always slightly more compelling than the last one.
Every engaging post, surprising image, or argument in your feed triggers a small dopamine pulse. The mechanism is structurally identical to what drives binge eating, compulsive shopping, or nicotine dependence. What makes scrolling uniquely effective as a dopamine delivery system is that it is frictionless. There is no effort required, no skill to develop, and no delay between the desire and the next hit.
When you put the phone down, dopamine levels fall. The brain, calibrated by several hours of rapid-fire stimulation, registers the drop as a deficit and generates the urge to return. This is not a weakness. It is a well-documented neurochemical correction mechanism. The problem is that this mechanism was not designed for a device always within arm’s reach.
Scrolling is cheap candy for the brain. It is effortless, immediately satisfying, and leaves the system wanting more without ever having been nourished.
The brain adapts to repeated stimulation by adjusting its baseline. Frequent exposure to high stimulation, low-effort content raises the threshold needed to experience satisfaction. Activities that were previously rewarding begin to feel effortful and under-stimulating by comparison. This is neuroadaptation. It is reversible, but it requires deliberate change.
Sustained heavy scrolling has been associated with shortened attention spans, reduced working memory performance, and increased difficulty with delayed gratification. None of these are permanent. The brain retains plasticity and can reorganise in response to new inputs. But it requires consistent exposure to activities that demand more from it than a social media feed does.
Social comparison, anxiety-inducing content, and fragmented information all activate stress pathways. Chronic low-level activation of those pathways, particularly in adolescents, is associated with increased rates of anxiety and depression. Social media is not the cause. It is a very efficient amplifier.
None of the following requires eliminating screens entirely. They require adding more friction to scrolling, redirecting attention, and giving the brain more durable reward pathways than a dopamine spike from a trending post.
- Set a Hard Limit on Screen Time. Restrict passive scrolling to 30 to 60 minutes a day and schedule it deliberately, the way you would a meeting, rather than treating it as a default filler activity. This puts you in control of when and where your attention goes.
- Curate What the Algorithm Shows You. Follow accounts that produce content requiring genuine engagement and self-improvement. Unfollow or mute sources that consistently generate stress, comparison, or outrage without useful information. This will help you nurture a healthier mindset.
- Replace Effortless Scrolling with Challenging Alternatives. Reading, writing, puzzles, and learning a new skill all require sustained attention and produce slower but more lasting neurochemical rewards. These activities rebuild the attention capacity that fragmented content consumption erodes over time.
- Stay Active. Physical activity increases brain-derived neurotrophic factor (BDNF), which supports neuroplasticity and cognitive repair. A 30-minute walk is sufficient to produce measurable changes in attention and mood. It does not need to be vigorous to be effective.
- Prioritise In-Person Connection. Face-to-face interaction activates social reward circuits more fully than digital communication. It also requires reading nonverbal cues, managing conversational rhythm, and tolerating ambiguity, all of which exercise the prefrontal cortex in ways that a comment thread does not.
- Seek Professional Help When It Is Needed. If screen use is causing significant distress, interfering with sleep, or is accompanied by persistent symptoms of anxiety or depression, a qualified therapist is the appropriate next step. Behavioural interventions for technology-related compulsions have been shown to be effective.
The takeaway: Brain rot is an imprecise term for a precise problem. The brain does not rot. It adapts. And when it adapts to cheap, effortless stimulation, the activities that require patience and depth begin to feel like work they were never designed to feel like.
The way out is incremental. Each choice to put the phone down and do something that requires more of you is a signal the brain responds to. The adaptation runs in both directions.
Reclaiming focus is not a question of motivation or discipline. It is a question of what you repeatedly ask your brain to focus on. Start small. Start today. The clarity that follows is not a reward you earn once. It is a state the brain returns to when you stop interrupting its concentration.
References
- Meshi D, Tamir DI, Heekeren HR. The emerging neuroscience of social media. Trends in Cognitive Sciences. 2015;19(12):771–782.
- Turel O, He Q, Xue G, Xiao L, Bechara A. Examination of neural systems sub-serving Facebook “addiction”. Psychological Reports. 2014;115(3):675–695.
- Shensa A, Escobar-Viera CG, Sidani JE, et al. Problematic social media use and depressive symptoms among U.S. young adults. Social Science & Medicine. 2017;182:150–157.
- Andrews S, Ellis DA, Shaw H, Piwek L. Beyond self-report: tools to compare estimated and real-world smartphone use. PLOS ONE. 2015;10(10):e0139004.
Zoey Fong is a science communicator and content strategist, translating complex biomedical research into strategic content for biotech and healthcare audiences. Based in Singapore. 7+ years in biomedical science · 8+ publications · PMP certified.
Part of the case study Neuroscience Education Series