Hysteria has not been a formal psychiatric or neurological diagnosis for decades. The term was progressively removed from the major diagnostic manuals during the second half of the twentieth century, replaced by a cluster of more specific conditions that carved up the enormous territory “hysteria” once covered. The most direct successor is functional neurological disorder, but pieces of the old concept also live on in somatic symptom disorder, dissociative disorders, and histrionic personality disorder. Understanding what happened to hysteria is really understanding how medicine stopped treating a vague, heavily gendered label as a single disease and started recognizing several distinct problems that had been lumped together for millennia.
Four Thousand Years of a Catch-All Diagnosis
Hysteria holds the dubious honor of being probably the oldest mental health condition attributed specifically to women, with descriptions dating to the second millennium BCE. For most of that history, the diagnosis swung between two frameworks: a medical one (the uterus was supposedly wandering around the body causing symptoms) and a supernatural one (afflicted women were possessed or practicing sorcery). Treatments ranged from herbal remedies and sexual prescriptions to punishment by fire.1PubMed Central. Women and hysteria in the history of mental health By the nineteenth century, the diagnosis had expanded to cover an extraordinary range of symptoms: paralysis, seizures, blindness, amnesia, fainting, emotional outbursts, and chronic pain, among many others. Jean-Martin Charcot and later Sigmund Freud reshaped hysteria into a psychological concept, linking it to repressed trauma and unconscious conflict. But even as the theoretical models grew more sophisticated, the diagnosis itself remained impossibly broad. Two patients labeled “hysterical” could have symptoms with nothing in common.
War complicated the picture further. When soldiers in World War I developed paralysis, tremors, and seizures without any detectable injury, military physicians called the condition “shell shock” or “war neurosis,” terms that were functionally equivalent to hysteria in men.2PubMed Central. From shell shock and war neurosis to posttraumatic stress disorder: a history of psychotraumatology The fact that healthy young men could develop the same symptoms as “hysterical” women undermined the uterine theory once and for all and also chipped away at the idea that hysteria was a single coherent disease. Over the following decades, psychiatrists began splitting the concept into separate diagnoses that could be defined, studied, and treated on their own terms.
The Diagnostic Successors
When the American Psychiatric Association overhauled its diagnostic manual in the 1980s and again in subsequent editions, “hysteria” disappeared as a named condition. Its former territory was divided among several categories, each capturing a different slice of what the old label had covered.
- Functional neurological disorder (also called conversion disorder): This covers the neurological symptoms that were historically the hallmark of hysteria: weakness, paralysis, tremors, seizures, blindness, or speech problems that cannot be explained by a known neurological disease. In the current DSM-5, it is listed as “functional neurological symptom disorder.”
- Somatic symptom disorder: This replaced older categories like somatization disorder and captures patients whose physical symptoms cause disproportionate distress or functional impairment, regardless of whether a medical explanation exists.
- Dissociative disorders: Amnesia, identity disruption, fugue states, and depersonalization were all historically lumped into hysteria. They now form their own diagnostic family. Dissociative amnesia, for instance, most commonly shows up as an inability to recall autobiographical information, sometimes accompanied by dissociative fugue, where a person travels or assumes a new identity without remembering their previous life.3DeckerMed Psychiatry. Dissociative Disorders and Their Clinical Management Part One: Dissociative Amnesia (Including Its Variant Dissociative Fugue)
- Histrionic personality disorder: This is the only current diagnosis that still carries a name etymologically linked to hysteria. It first appeared in the DSM-II under the older term “hysterical personality” and was renamed in the DSM-III.4PubMed Central. Historical roots of histrionic personality disorder The condition is characterized by attention-seeking behavior and a shallow, emotionally volatile interpersonal style.5Personality Disorders. Histrionic Personality Disorder
Of these successors, functional neurological disorder has received the most research attention and is the one most directly analogous to what nineteenth-century neurologists meant by “hysteria.” It is also the one where the science has moved most dramatically in recent years.
Functional Neurological Disorder Up Close
Functional neurological disorder, or FND, describes neurological symptoms that are real and often disabling but arise from how the brain is functioning rather than from structural damage like a stroke or a tumor. A person with FND might have a limb that genuinely will not move, seizure-like episodes, vision loss, or difficulty speaking. These are not faked or imagined; brain imaging studies consistently show measurable differences in how the brains of FND patients process movement, sensation, and emotion compared to healthy controls.
Over centuries, various explanations have been proposed for these kinds of symptoms: supernatural influences, malfunctioning reproductive organs, the bodily expression of painful emotions, and more recently, cognitive distortions involving attention and prediction.6PubMed Central. A historical review of functional neurological disorder and comparison to contemporary models The modern understanding draws heavily on a framework called predictive processing, which views the brain as constantly generating predictions about what the body should be feeling and doing, then updating those predictions based on actual sensory input. In FND, that updating process appears to go wrong. The brain’s confidence in its own predictions can surge, especially during periods of heightened arousal, causing an unhelpful expectation to override corrective feedback and produce motor or sensory symptoms.7PubMed. Precision dynamics of predictive coding in functional neurological disorder In practical terms, this means the brain is sending commands (or withholding them) based on faulty internal signals, producing genuine neurological symptoms even though the underlying hardware is intact.
How Doctors Diagnose FND Today
One of the most important shifts in how FND is handled is that it is no longer supposed to be a “diagnosis of exclusion,” meaning something you land on only after ruling out everything else. Clinicians now look for positive signs: specific, observable inconsistencies in how symptoms behave that point toward a functional rather than structural cause.8PubMed Central. Positive Clinical Signs in Functional Neurological Disorders: A Narrative Review and Development of a Clinical Decision Tool These signs have been validated in research and are increasingly used at the bedside.
A well-known example is Hoover’s sign, used to assess functional weakness in a leg. A patient lying on their back is asked to flex the opposite hip against resistance. If the supposedly weak leg involuntarily extends during this maneuver, it demonstrates that the motor pathways are intact and the weakness is functional rather than due to nerve or muscle damage. Other positive signs include distractibility of tremors (a functional tremor often changes frequency or stops when the patient is asked to perform a rhythmic task with the other hand), seizure-like episodes where the eyes remain closed throughout (unusual in epileptic seizures), and inconsistency between examination findings and functional ability in everyday tasks.
The shift toward positive diagnosis matters because it allows doctors to tell patients what they have, not just what they don’t have. Being told “your MRI is normal, so we can’t find anything wrong” is deeply unsatisfying and can feel dismissive. Being told “I found specific signs on your exam that tell me this is a functional neurological disorder, and here is how it works” gives the patient a name for their condition, a framework for understanding it, and a path toward treatment.
What Brain Imaging Reveals
Neuroimaging research has started to map what goes wrong in the brains of people with FND, and the picture involves disrupted communication between networks rather than damage to any single area. Studies consistently find altered connections between emotion-processing regions (the amygdala and cingulate-insular cortex) and motor control circuits. In particular, the amygdala shows heightened reactivity and increased coupling with motor areas, which may represent a marker of excessive limbic influence over movement and sensation.9PubMed Central. Neuroimaging in Functional Neurological Disorder: State of the Field and Research Agenda In simpler terms, the brain regions responsible for emotional arousal appear to have an outsized influence on the regions controlling the body.
Research also points to abnormalities in an area called the right temporo-parietal junction, a brain region involved in distinguishing self-generated actions from externally caused events. Patients with FND show reduced flexibility in switching between brain states and altered connectivity between this region and networks involved in attention and bodily awareness.10PubMed Central. Ultra-high field brain MRI for functional neurological disorder: opportunities and challenges This is consistent with the clinical experience that many FND patients describe their symptoms as involuntary and alien, as though the limb or voice belongs to someone else. The brain regions that normally tag actions as “mine” seem to be misbehaving.
Despite these advances, the findings are not yet consistent enough to serve as a diagnostic biomarker. Brain scans can show group-level differences between FND patients and healthy controls, but they cannot reliably diagnose an individual patient. The diagnosis still rests on clinical examination, and imaging research functions more as a way of understanding mechanism than as a practical diagnostic tool.
Treatment That Works
Treatment for FND has also moved well beyond the vague prescriptions and moral judgments that characterized approaches to hysteria. The evidence base is strongest for a combination of specialized physiotherapy and cognitive behavioral therapy. A randomized clinical trial found that a structured program pairing twelve sessions of individualized physiotherapy with four group sessions of cognitive behavioral therapy effectively improved both movement symptoms and physical quality of life in patients with functional movement disorders.11JAMA Neurology. Combined Physiotherapy and Cognitive Behavioral Therapy for Functional Movement Disorders: A Randomized Clinical Trial
The physiotherapy component is not like standard rehabilitation after a stroke. It typically involves movement retraining, using distraction and automatic movements to demonstrate to the patient’s brain that the affected body part can work normally. The cognitive behavioral component addresses the beliefs, attention patterns, and avoidance behaviors that perpetuate symptoms. One treatment approach explicitly draws on the idea that FND arises in part from a nocebo-like mechanism: patients come to believe they are neurologically damaged, and that belief itself drives the dysfunction. Treatment then involves transparently sharing this model with patients and working to update those beliefs.12PubMed. A Novel Treatment Protocol (Nocebo Hypothesis Cognitive Behavioural Therapy; NH-CBT) for Functional Neurological Symptom Disorder/Conversion Disorder: A Retrospective Consecutive Case Series
Access remains a major barrier. Specialized FND clinics exist in some academic medical centers, but in many parts of the world there are few clinicians trained in delivering these interventions. Patients frequently see multiple specialists over years before receiving a correct diagnosis, let alone appropriate treatment.
The Stigma Problem
If there is one feature of hysteria that has stubbornly persisted into the modern era, it is the stigma attached to the diagnosis and to the people who carry it. Research consistently finds that patients with FND experience stigma from multiple directions: from healthcare providers who dismiss or minimize their symptoms, from friends and family who struggle to understand a condition that looks neurological but has no visible lesion on a scan, and from within themselves as they internalize doubt about the reality of their own experience.13PubMed. How stigma unfolds for patients with Functional Neurological Disorder
That stigma has measurable consequences. It creates obstacles to diagnosis and treatment, prolongs the diagnostic journey, and drives repeated and often unnecessary use of healthcare resources as patients seek a “real” explanation for their symptoms.14PubMed. Stigma and functional neurological disorder: a research agenda targeting the clinical encounter Research also shows that higher levels of stigma correlate with greater depression, anxiety, and poorer social functioning in FND patients.15BMJ Neurology Open. Illness perceptions, experiences of stigma and engagement in functional neurological disorder (FND): exploring the role of multidisciplinary group education sessions The old binary thinking, that symptoms are either “real” (caused by detectable tissue damage) or “not real” (therefore psychological and presumably less valid), is deeply embedded in both medical culture and public understanding. FND falls into the gap between those categories, and patients suffer for it.
The shift away from “hysteria” was partly motivated by a desire to reduce this stigma, but renaming has only done so much. Patients still report feeling “othered” by a healthcare system that does not know what to do with them. Progress will likely require not just better terminology but better education for clinicians about what FND actually is and how to communicate the diagnosis without implying that symptoms are imagined.
Mass Psychogenic Illness and Social Media
One of the more striking modern developments touches on another legacy of the hysteria concept: mass psychogenic illness, sometimes still called “mass hysteria” in popular language. These are episodes in which groups of people develop physical symptoms without a shared physical cause, often triggered by anxiety, stress, or social suggestion. Studies of chemical-spill incidents found that roughly one in six episodes where people reported symptoms were actually probable mass psychogenic illness, with odor as a strong predictor and schools and healthcare facilities as the most common settings.16PubMed. Frequency and predictors of mass psychogenic illness
What’s new is that social media appears to have enabled a form of mass psychogenic illness that does not require people to be in the same physical space. During the pandemic era, clinicians across several countries reported a sudden influx of young people, predominantly teenage girls, presenting with functional tic-like behaviors. Many of these patients had been watching content by popular social media creators who had tic disorders, and their symptoms closely resembled those seen on screen rather than the typical presentation of Tourette syndrome. Researchers described this as “mass social media-induced illness,” the first documented outbreak of mass sociogenic illness spread solely through digital platforms.17PubMed Central. Stop that! It’s not Tourette’s but a new type of mass sociogenic illness In Germany, the apparent “virtual index case” was one of the country’s most popular YouTube creators, and affected teenagers presented with similar or identical functional behaviors that could be clearly differentiated from genuine tics.
Further study confirmed that symptoms in these patients largely overlapped with those presented by the social media figures they had watched, supporting the role of digital exposure as a trigger.18PubMed Central. Mass social media-induced illness presenting with Tourette-like behavior These episodes are still being followed longitudinally, with researchers tracking outcomes to understand whether the functional tic-like behaviors resolve or persist over time.19PubMed Central. Long-Term Follow-Up of Patients with Mass Social Media-Induced Illness Presenting with Functional Tic-like Behaviors The phenomenon illustrates that the social and suggestive mechanisms underlying mass psychogenic illness have not disappeared with the death of the hysteria label; they have simply found new channels of transmission.
How Cultural Context Shapes Functional Symptoms
The way functional symptoms present and the way they are understood vary considerably across cultures, a complexity that the old one-size-fits-all “hysteria” label completely failed to accommodate. Different cultures have different idioms of distress: the physical manifestations of psychological suffering are shaped by cultural expectations about what symptoms mean, how they should be expressed, and whether emotional distress is an acceptable thing to communicate directly. There has been considerable dissatisfaction among researchers with how concepts like somatization have been defined and applied across non-Western cultures, where the boundary between “physical” and “psychological” symptoms may be drawn very differently, or may not be drawn at all.20PubMed Central. The Concept of Somatisation: A Cross-cultural perspective
This matters practically because a diagnostic framework developed primarily in Western clinical settings may not translate cleanly to patients from different cultural backgrounds. A person presenting with functional seizures in rural South Asia and a person presenting with functional weakness in a London neurology clinic may both have FND, but their symptom profiles, their explanatory models for what is happening to them, and the social consequences of their illness may look completely different. The move away from “hysteria” was a step in the right direction, but the replacement diagnoses still carry assumptions about how the mind and body relate that are not universally shared. Clinicians working across cultural contexts need to be aware that the framework itself is culturally situated, not just the symptoms it describes.
Where FND Research Is Heading
The predictive processing model has become one of the most active areas of FND research. The basic idea, that the brain generates predictions about what it should be sensing and doing and that FND involves those predictions overriding actual sensory feedback, is being refined into increasingly specific accounts. Recent work models the brain’s confidence in its own predictions as a dynamic quantity that fluctuates with arousal: when arousal spikes, the brain can become excessively confident in an incorrect prediction, suppress corrective sensory information, and produce symptoms across motor, sensory, cognitive, and visceral domains.7PubMed. Precision dynamics of predictive coding in functional neurological disorder This framework is appealing because it provides a unified explanation for why FND symptoms are so variable, why they fluctuate, and why emotional states and attention so reliably influence them.
Neuroimaging is also pushing into higher resolution. Conventional clinical MRI has shown group-level brain differences in FND patients, but findings across studies have been only partially consistent, likely because the relevant changes occur at a scale below the resolution of standard scanners.10PubMed Central. Ultra-high field brain MRI for functional neurological disorder: opportunities and challenges Ultra-high-field MRI, operating at seven Tesla and above, offers substantially better spatial resolution and may be able to detect subtle structural and functional changes that conventional imaging misses. Whether this will eventually lead to objective biomarkers for FND remains an open question, but the field is actively pursuing it. For patients who have long been told that their scans are “normal” and therefore their symptoms are not real, the prospect of imaging that can actually visualize what is going wrong in their brains carries real significance, even if it is still years from clinical use.