用致幻剂治疗精神障碍：研究综述
摘要
约翰斯·霍普金斯大学迷幻药与意识研究中心主任 Matthew Johnson 博士探讨了致幻化合物的药理学、临床应用及治疗机制，涵盖裸盖菇素（psilocybin）、MDMA、氯胺酮、DMT 和 LSD。对话涉及这些物质如何改变自我表征与神经预测模型，以及一次结构化临床致幻治疗从筛查到整合的完整过程。
核心要点
- 致幻剂的主要作用机制是挑战大脑的预测模型 —— 瓦解僵化的心理框架，尤其是围绕自我认同的框架，这或许可以解释其在截然不同病症中均具有治疗效果的原因。
- 血清素 2A 受体是经典致幻剂（裸盖菇素、LSD、DMT、麦斯卡林）的主要作用靶点，但其深刻效应背后超越单纯受体结合的机制仍知之甚少。
- 自我表征的改变似乎是共同的治疗核心 —— 无论是治疗抑郁症、癌症相关焦虑还是成瘾 —— 这比致幻体验的具体内容更为关键。
- HPPD（卤代药物持续性知觉障碍）确实存在，但极为罕见，在数千名临床试验参与者中从未被观察到 —— 仅见于非法使用情境，提示剂量不确定、多药合用或罕见神经系统易感性等因素可能是诱因。
- 疗程后的整合 —— 书写体验、与引导师讨论，并认真对待这段经历 —— 其治疗价值可能与疗程本身同等重要。
- 闪回在传统意义上很可能与药物无直接关联；大多数属于状态依赖性记忆提取，或是使用后一两天内出现的短暂感知异常。致幻剂储存于脂肪组织的说法没有科学依据。
- 氯胺酮（以 Spravato/艾司氯胺酮的形式）已获 FDA 批准用于难治性抑郁症，但其抗抑郁效果持续约一周，而裸盖菇素的效果可持续一年或更长 —— 这一差距可能与氯胺酮是否在完整的致幻治疗模式下给药有关。
- 心态与环境（Set and setting） —— 治疗关系、准备性会谈以及物理环境 —— 对致幻体验及其结果具有决定性影响。
- 重大人生决定（结束关系、辞职等）应在致幻疗程结束后至少推迟一到两周再做。
详细笔记
什么是致幻剂？
“致幻剂”这一术语更多属于文化概念，而非药理学范畴，涵盖多个不同药物类别。Johnson 博士将致幻剂广义定义为能够深刻改变个体现实感（包括自我感）的物质。
主要类别：
- 经典致幻剂（血清素 2A 激动剂）：裸盖菇素、LSD、DMT、麦斯卡林
- 按结构分为色胺类（裸盖菇素、DMT）和苯乙胺类（麦斯卡林）
- NMDA 拮抗剂：氯胺酮、苯环利定（PCP）、右美沙芬
- κ-阿片受体激动剂：Salvinorin A（来自墨西哥鼠尾草）
- 情感接触剂/共情致幻剂：MDMA —— 通过血清素释放发挥作用（使突触中血清素大量涌入），而非像经典致幻剂那样作为受体激动剂
“所有经典致幻剂均作为血清素 2A 受体的激动剂或部分激动剂发挥作用。“
经典致幻剂的作用机制
- 裸盖菇素在结构上与血清素相似（均为色胺类），但以不同方式激活 5-HT2A 受体 —— 触发不同的下游信号通路
- 经典致幻剂还会增加谷氨酸传递，这或许可以解释其与氯胺酮致幻效应的重叠之处
- 大脑被描述为一台预测机器，以自上而下的方式运作；致幻剂似乎能瓦解或动摇这些预测模型
- 神经可塑性由该体验所触发；实际的神经重塑是一个过程，而非单一事件，可能历经数月乃至数年逐步展开
裸盖菇素临床疗程：分步解析
筛查：
- 结构化精神科访谈（采用 DSM 诊断标准）
- 排除标准包括：精神病性障碍（精神分裂症）、双相情感障碍（尤其是有躁狂特征者）、重大心血管疾病
准备阶段（跨多次会谈，共计数小时）：
- 参与者与引导师/治疗师建立治疗性信任关系
- 告知体验可能存在的广泛差异 —— 被形容为”全能型”体验：可能是一生中最美好或最恐惧的经历
给药：
- 以小胶囊形式给予纯合成裸盖菇素（白色粉末）
- 典型治疗剂量范围：20–30 mg（历史上按体重调整，参照约 70 kg；新方案正逐步取消此调整）
- 起效时间：15–60 分钟；平均约 30 分钟
- 持续时间：约 6–8 小时
疗程期间：
- 参与者躺在沙发上，佩戴眼罩（非”蒙眼布”）以促进内省
- 播放音乐
- 每约 30 分钟监测一次血压和脉搏
- 备有心血管干预方案（舌下含服硝酸甘油）；极少需要使用
- 情绪表达 —— 包括哭泣 —— 受到明确欢迎和鼓励
- 全程有引导师陪伴；治疗性疗程中不进行认知任务或功能性磁共振成像
整合阶段：
- 疗程约 5–6 小时后进行简短的初步讨论（下午晚些时候）
- 当晚作业：书写体验（无字数要求，不做评判）
- 次日与引导师进行 1–2 小时的整合会谈，讨论体验内容及其意义
- 采用支持性、非指导性的治疗风格；人本主义取向，给予无条件积极关注
- 鼓励参与者至少在 1–2 周内不做重大人生决定
治疗机制：自我表征
这一假说被认为能解释致幻剂为何在如此多样的病症中均有效：
“共同的核心是自我表征的持久改变 —— 一个人与世界之间的根本关系。”
- 自我是大脑最大的预测模型：“我是一个吸烟者”、“我是一个抑郁的人”、“我是一个失败者”
- 致幻剂似乎能瓦解或松动这一模型，使其得以以不同方式重建
- 这并非由语言或正向自我暗示所驱动 —— 神经网络因体验而改变，而非因言语而改变
- 爱上一支笔，或处理童年创伤，最终或许殊途同归：与自我和世界之间的关系发生转变
- 记忆再巩固可能发挥作用，尤其在创伤处理中 —— 记忆似乎在体验过程中被以持久的方式重新加工
临床案例示例：
- 戒烟：参与者报告突然意识到自己可以简单地决定不再吸烟 —— 身份从”戒不掉的烟民”转变为非吸烟者
- 癌症患者：对存在性恐惧的缓解；认识到痛苦部分源于自身；重新投入生活
- 这些被描述为**“恍然大悟”的体验** —— 看似显而易见的洞见，却是之前无法触及的
氯胺酮与 NMDA 拮抗剂
- 氯胺酮（以 Spravato/艾司氯胺酮的形式）已获 FDA 批准用于难治性抑郁症
- 目前的临床模式并不将致幻体验视为具有治疗意义 —— 其被当作”副作用”处理
- 抗抑郁效果持续约一周，而裸盖菇素的效果可持续一年或更长
- 俄罗斯研究者 Krupitsky 在 1990 至 2000 年代将大剂量氯胺酮作为致幻治疗用于海洛因和酒精成瘾，成功率较高
- 氯胺酮与裸盖菇素在效果持久性上的差距，可能反映了氯胺酮缺乏致幻治疗框架的现状
- “K 洞”（K-hole）指较高剂量（约 75–100 mg 以上）时出现的重度解离状态
闪回与 HPPD
卤代药物持续性知觉障碍（HPPD）：
- DSM 中的真实诊断：持续性视觉障碍（光晕、残影、色彩失真），持续数月，造成临床痛苦
- 在现代及历史研究时期数千名临床试验参与者中从未被观察到
- 仅见于非法使用情境 —— 可能与剂量不明、纯度问题、多药合用有关，
English Original 英文原文
Psychedelics for Treating Mental Disorders: A Research Overview
Summary
Dr. Matthew Johnson, Director of the Center for Psychedelic and Consciousness Research at Johns Hopkins, explores the pharmacology, clinical applications, and therapeutic mechanisms of psychedelic compounds including psilocybin, MDMA, ketamine, DMT, and LSD. The conversation covers how these substances alter self-representation and neural models, and what a structured clinical psychedelic therapy session actually looks like from screening through integration.
Key Takeaways
- Psychedelics work primarily by challenging the brain’s predictive models — dissolving rigid mental frameworks, particularly around self-identity, which may explain their therapeutic effects across vastly different conditions.
- The serotonin 2A receptor is the primary target of classic psychedelics (psilocybin, LSD, DMT, mescaline), though the mechanism of their profound effects beyond simple receptor binding remains poorly understood.
- Changes in self-representation appear to be the common therapeutic denominator — whether treating depression, cancer-related anxiety, or addiction — more so than the specific content of the psychedelic experience.
- HPPD (hallucinogen-persisting perceptual disorder) is real but extremely rare, and has never been observed in thousands of clinical trial participants — only in illicit use contexts, suggesting factors like dose uncertainty, polypharmacology, or rare neurological susceptibility.
- Integration after the session — writing about the experience, discussing it with guides, and taking it seriously — may be as therapeutically important as the session itself.
- Flashbacks are likely not drug-related in the traditional sense; most are either state-dependent memory retrieval or brief perceptual anomalies in the day or two following use. Fat storage of psychedelics has no scientific evidence.
- Ketamine (as Spravato/esketamine) is FDA-approved for treatment-resistant depression, but its antidepressant effects last roughly one week vs. one year or more for psilocybin — a gap that may relate to whether ketamine is administered using a full psychedelic therapy model.
- Set and setting — the therapeutic relationship, preparatory sessions, and physical environment — critically shape the psychedelic experience and its outcomes.
- Big life decisions (ending relationships, quitting jobs) should be deferred at least one to two weeks following a psychedelic session.
Detailed Notes
What Is a Psychedelic?
The term “psychedelic” is more cultural than pharmacological, spanning multiple distinct drug classes. Dr. Johnson defines psychedelics broadly as substances with the ability to profoundly alter one’s sense of reality, including the sense of self.
Major classes:
- Classic psychedelics (serotonin 2A agonists): psilocybin, LSD, DMT, mescaline
- Structurally divided into tryptamines (psilocybin, DMT) and phenethylamines (mescaline)
- NMDA antagonists: ketamine, PCP, dextromethorphan
- Kappa-opioid agonists: Salvinorin A (from Salvia divinorum)
- Entactogens/Empathogens: MDMA — works via serotonin release (flooding the synapse), not receptor agonism like classic psychedelics
“All of the classic psychedelics serve as agonist or partial agonists at the serotonin 2A receptor.”
How Classic Psychedelics Work
- Psilocybin is structurally similar to serotonin (both tryptamine-based), but activates the 5-HT2A receptor differently — triggering alternate downstream signaling
- Classic psychedelics also increase glutamate transmission, which may explain overlap with ketamine’s psychedelic effects
- The brain is described as a prediction machine, operating top-down; psychedelics appear to dissolve or destabilize these predictive models
- Neuroplasticity is triggered by the experience; the actual neural rewiring is a process, not a single event, and may unfold over months or years
The Clinical Psilocybin Session: Step by Step
Screening:
- Structured psychiatric interviews (using DSM criteria)
- Exclusion criteria include: psychotic disorders (schizophrenia), bipolar disorder (particularly manic features), significant cardiovascular disease
Preparation (several hours across multiple sessions):
- Participants develop therapeutic rapport with their guides/therapists
- Informed of the wide variability of possible experiences — described as “all arounders”: potentially the most beautiful or most terrifying experience of one’s life
Dosing:
- Pure synthetic psilocybin administered in a small capsule (white powder)
- Typical therapeutic dose range: 20–30 mg (historically body-weight adjusted to ~70 kg; newer protocols dropping this adjustment)
- Onset: 15–60 minutes; average ~30 minutes
- Duration: approximately 6–8 hours
During the session:
- Participants lie on a couch wearing eyeshades (not “blindfolds”) to encourage internal focus
- Music is played
- Blood pressure and pulse monitored every ~30 minutes
- Protocol exists for cardiovascular intervention if needed (nitroglycerin sublingually); rarely required
- Emotional expression — including crying — is explicitly welcomed and encouraged
- Guides are present throughout; no cognitive tasks or fMRI during therapeutic sessions
Integration:
- Brief initial discussion ~5–6 hours into the session (late afternoon)
- Overnight homework: write about the experience (no length requirement, no judgment)
- Next-day 1–2 hour integration session with guides to discuss the experience and its meaning
- Supportive, non-directive therapy style; humanistic approach with unconditional positive regard
- Participants encouraged not to make major life decisions for at least 1–2 weeks
Therapeutic Mechanisms: Self-Representation
The leading hypothesis for why psychedelics work across such diverse conditions:
“The common denominator are persisting changes in self-representation — the fundamental relationship of a person in the world.”
- The self is the brain’s largest predictive model: “I am a smoker,” “I am a depressed person,” “I am a failure”
- Psychedelics appear to dissolve or loosen this model, allowing it to be rebuilt differently
- This is not driven by language or affirmations — neural networks change in response to experience, not words
- Falling in love with a pen, or processing childhood trauma, may both lead to the same endpoint: a transformed relationship with self and world
- Memory reconsolidation may play a role, particularly in trauma processing — memories appear to be reprocessed during the experience in lasting ways
Examples from clinical work:
- Smoking cessation: participants report suddenly recognizing they can simply decide not to smoke — identity shift from “I am a smoker who can’t quit” to a non-smoker
- Cancer patients: reduction in existential fear; recognition that suffering was partly self-generated; renewed engagement with life
- These are described as “duh” experiences — insights that seem obvious but were previously inaccessible
Ketamine and NMDA Antagonists
- Ketamine (as Spravato/esketamine) is FDA-approved for treatment-resistant depression
- Current clinical model does not frame the psychedelic experience as therapeutically relevant — it is treated as a “side effect”
- Antidepressant effects last approximately one week, versus one year or more for psilocybin
- Russian research by Krupitsky in the 1990s–2000s used high-dose ketamine as psychedelic therapy for heroin and alcohol addiction, with high success rates
- The gap in durability between ketamine and psilocybin may reflect the absence of a psychedelic therapy framework for ketamine
- A “K-hole” refers to a heavily dissociative state at higher doses (~75–100 mg+)
Flashbacks and HPPD
Hallucinogen-Persisting Perceptual Disorder (HPPD):
- Real diagnosis in the DSM: persisting visual disturbances (halos, trails, color distortions) lasting months, causing clinical distress
- Never observed in thousands of clinical trial participants across the modern and historical research eras
- Only documented in illicit use — likely due to unknown doses, purity issues, polypharmacology,