Northeastern · 心理与社会行为· Katya Poltorak·2026-10-21 04:38· 1 天前精选AI 评分58

神经影像综述：所谓“健康大脑”或取决于社会关系

What does a healthy brain look like? Turns out it’s all relative.

内容导读

美国东北大学伦敦分校研究者Haily Merritt及同事在一项综述中提出，fMRI扫描显示的脑活动模式会随一个人的社会关系经历而不同，因此不存在通用的心理健康或疾病脑部标志。综述聚焦默认模式网络：同一连接模式在不同社会处境下可能对应适应或回避，这也被用来解释以往关于默认模式网络与抑郁关联方向不一致的结果。报道未交代纳入研究的数量与检索方式，结论范围限于该综述覆盖的研究。

推荐理由

报道介绍的是一项综述，而非新实验；文中未给出纳入研究数量、检索方式与样本构成，因此“社会关系塑造脑活动”的结论范围以该综述所覆盖的研究为限。

中文解读

一个找不到的“标准脑”

神经科学长期在寻找某种通用的生物标志物：如果扫描能给出一个标准答案，精神健康问题的诊断与治疗就会简单许多。美国东北大学伦敦分校研究者Haily Merritt与同事在近期一项综述中提出的看法与此相反——扫描图像本身并不足以说明问题，还需要知道这个人的社会关系如何塑造了他的脑活动。

这项工作的做法不是新做实验，而是把已有研究中同时包含fMRI扫描与人际关系信息的部分放在一起比较。报道没有交代纳入研究的数量、检索方式或样本构成，因此这里的结论应理解为对该批研究的综合判断，而不是一项新的实证发现。

默认模式网络里的矛盾

综述特别提到默认模式网络（DMN）。这一网络中的区域参与解读他人情绪和管理自身感受，其内部连接的强弱、以及与其他脑区的联系，会随一个人的过往经历和当前社会关系而变化。

Merritt指出，过去的研究中，有的把默认模式网络某些区域之间交流增强与抑郁联系起来，有的则把相反的模式与同一状况联系起来。把社会处境纳入考虑后，这种矛盾有了一种解释：在一种环境里，更强的默认模式网络连接是有益的；在另一种环境里，它可能是有害的。

这并不意味着社会关系已被证明导致某种脑连接变化。报道给出的一个可能路径是应激反应：皮质醇在压力下释放，而支持性的接触可以使其下降；长期来看，应激激素会改变脑区之间交流的容易程度，从而改变扫描所测到的模式。这一机制在文中以“一种可能”的方式提出。

被当成症状的应对方式

纽约的心理治疗师Michael Herman在报道中提出，临床工作者可能过快地把某些行为计为病征，例如一个人表现得戒备、过度警觉或坚持自力更生。但这些行为也可能是在反复被辜负之后形成的保护。

创伤专家、《依恋的力量》作者Diane Poole Heller则提到，症状相似的人可能需要不同的指引：有人需要学习设立边界，有人需要在关系中愈合。她强调，鼓励更多接触只有在理解这种接触的质量与安全性时才有帮助。这些是受访者的临床观点，不是综述本身的研究结果。

报道还提到综述中描述的一个反馈循环：有可靠支持经历的人在困难时更愿意接受帮助，每一次积极的社会互动又会增强脑对未来压力的适应力；而依恋较弱的人倾向于退开，错过所需的帮助。

对诊断与治疗意味着什么

按照报道的表述，这类视角的潜在意义在于帮助临床工作者区分疾病与习得的应对方式，并在处理痛苦来源时减少症状复发，长期看可能减少误诊和治疗中的反复试错。这些是文章提出的方向性判断，报道没有给出对应的临床试验数据或效果测量。

Merritt本人把这项工作的落点表述为“投资于我们的关系，并有意识地对待它们”。这句话是研究者的主张，而非综述得出的因果结论。

正文 · 原文

What does a healthy brain look like? It depends on the company you keep.

A brain scan can’t tell the whole story. Northeastern researchers explore how our closest ties affect neural activity — and how understanding those bonds could change mental health care.

An image scan of neural brain connections, with colorful webs criss crossing the brain. — A scan might show connections in your brain, but the people in your life help explain what they mean. Getty Images

by Katya Poltorak October 20, 2026

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Squishy, wrinkled, weighing about as much as a cantaloupe, the brain may not be much to look at from the outside. Yet with a network of roughly 86 billion neurons, it generates more impulses daily than all the smartphones on the planet combined.

Scientists can track all that activity with scans. But what does a well-balanced brain actually look like?

Spoiler alert: new research says there’s no universal signature of mental health — or illness.

“A lot of the work in neuroscience is trying to identify some kind of universal biomarker,” said Northeastern University London researcher Haily Merritt. To do this, scientists use techniques like functional magnetic resonance imaging (fMRI), which measure changes in blood oxygen levels.

In a recent study, Merritt and her colleagues argue that scans look different depending on how a person’s social relationships have shaped their brain activity. Behaviors that let someone cope in one environment may prove unhelpful in another context, leaving unique neural traces that make the search for a universally “healthy brain” a perpetual wild goose chase.

“What is healthy depends on experience,” Merritt explained.

For example, a certain pattern could reflect a useful adaptation in a person lacking strong supports, but might signal avoidance in someone with a solid crew.

Related: What regular music practice means for a developing brain

The insights point clinicians to better treatment strategies and improved diagnosis by helping them distinguish illness from learned ways of coping while addressing the patient’s sources of distress in a way that prevents symptoms from returning. In the long term, this could mean fewer misdiagnoses and less trial and error in treatment. The findings also explain why the search for markers of mental health disorders kept producing conflicting answers.

Portrait of Haily Merritt with magenta hair and a nose ring in a black turtleneck against a white backdrop — Northeastern University London researcher Haily Merritt studies how close relationships shape brain activity and what those connections mean for mental health care. Courtesy photo

“This is a cornerstone of ‘treating the patient, not the problem,’” Michael Herman, a psychotherapist at Tribeca Therapy in New York City, told Northeastern Global News.

Merritt and her colleagues reviewed studies that paired fMRI scans with information about people’s relationships to examine neural connection patterns in different contexts.

To Merritt, the most profound insight was the fact that social bonds leave a visible mark on the brain at all.

“Our social relationships are really important for how we engage with the world,” she said.

The imprint was especially pronounced in the area known as the default mode network (DMN).

Regions in the DMN are involved in decoding other people’s emotions and managing one’s own feelings. The strength of the connections between them — and their links to other brain areas — varies with a person’s history and current social ties, Merritt explained.

For example, past studies connected an increase in communication between certain parts of the DMN with depression, while others linked the opposite pattern with the same condition, Merritt said. Factor in the social context that shaped brain activity, and the apparent contradictions start to make sense.

“In one environment, more default mode connectivity is good. And in another, it’s actually harmful,” Merritt explained.

Patterns of activity throughout the brain are linked to behaviors, which also make more sense in context. Understanding this can benefit clinicians who may otherwise be quick to count a behavior that’s serving a useful purpose as a sign of illness, Herman noted.

“They might see someone guarded, hypervigilant, or committedly self-reliant, and see a problem that needs to be fixed,” he suggested.

However, keeping people at bay may have offered protection after repeated betrayals.

The social context also explains why people with similar symptoms might need different guidance.

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One patient might benefit from learning to set boundaries, while another could heal by letting people in, trauma expert and author of “The Power of Attachment” Diane Poole Heller suggested.

“Encouraging more contact is only helpful when we understand the quality and safety of that contact,” she added.

The study mentions a feedback loop that forms when people with a history of reliable support become more receptive to help during difficult times. Each positive social encounter also builds the brain’s resilience to future stress. Those with weaker attachments, however, tend to back away, missing out on the much-needed assistance.

Herman said this dynamic underscores why therapists should pay close attention to a patient’s past.

“We can carry our earliest relationships inside us as blueprints for what to expect from other people,” he explained. Mental health struggles make it difficult to get past the assumption that reaching out won’t do any good — and the lack of close ties and strong social bonds makes recovery even harder.

But how exactly does the social environment turn into physical differences that show up on brain scans in the first place?

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One possibility involves the stress response. Cortisol is a hormone released under stress, and simply holding someone’s hand in support can bring it down, Merritt explained.

“When we feel supported … our stress responses calm and our sense of threat eases,” Herman said. “Even actual pain can feel less intense.”

Over time, stress hormones change how readily brain regions communicate, altering patterns researchers measure on scans.

Other emotional encounters leave their own imprint, according to Paul Hokemeyer, founder of the Drayson Mews, a London-based mental health advisory firm that provides consulting services.

Repeated neural responses to positive and painful experiences form “an unconscious map” the brain uses to gauge whether new people can be trusted, he said.

To Merritt, the study’s findings are “a call to invest in our relationships and approach them mindfully,” she said.

Katya Poltorak is a science reporter at Northeastern Global News. Email her at e.poltorak@northeastern.edu.