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Play today's Psychology caseFive progressive clues
These are the case findings in their original reveal order, moving from the broader presentation to the most discriminating evidence.
Clue 1
A 22-year-old student books the appointment herself, then spends the first minute apologising for taking up anyone’s time. Last autumn was a bad one: her parents’ divorce came through in the same term that a four-year relationship ended. In the months that followed, something began that she cannot put a name to. She still gets to her lectures and still works her weekend shifts, but she has stopped answering her friends, and she is frightened. She has already decided what this means. She thinks she is going mad.
Clue 2
Asked to describe it, she picks her words carefully, watching for the moment you decide she is unwell. For five months it has been like standing a few steps behind herself and watching: her hands move, her voice says the right things, and none of it feels like hers. And the world sits behind glass. Colours have gone flat, rooms she has known for years feel like a set someone built, and the whole day has the texture of a dream she is not quite inside.
Clue 3
Two things about the shape of it. In the first few weeks there were about six surges of racing heart and breathlessness, each over within minutes; those stopped months ago and the detachment did not go with them. It is there all day on the calmest afternoon, between the surges and long after the last one. And it is not chemical: she used cannabis occasionally in her first two years at university and stopped eight months ago, three months before any of this began. Nothing since.
Diagnosis
Depersonalization/Derealization Disorder
Why the diagnosis fits
The whole case turns on the thing she keeps repeating, which is also the thing that frightens her most: she knows it is not real. That preserved insight is not a detail — it is a diagnostic criterion. Depersonalization/derealization disorder requires persistent or recurrent experiences of detachment from the self, from the surroundings, or both; reality testing unaffected by those experiences; clinically significant distress or impairment of functioning; symptoms not attributable to substance use or another medical condition; and no other psychiatric disorder that explains the picture better. She meets all five. She describes standing a few steps behind herself while the world sits behind glass, continuously for five months. She is unshakeable that the room is really there. She is still getting to lectures and still working weekends, but she has withdrawn from her friends and has decided this means she is losing her mind. She stopped cannabis three months before any of it began and the urine screen is negative. The mild-to-moderate low mood came afterwards and is about the experience rather than the cause of it. The negatives are not padding — they are the diagnosis. The anxiety surges stopped months ago and the detachment stayed, which is what separates this from panic disorder, where acute anxiety is the centre of gravity. Nothing intrudes, replays, or wakes her, which is what separates it from post-traumatic stress disorder. And the electroencephalogram matters because detachment of epileptic origin has a strong association with frontal lobe epilepsy; electroencephalography is how that is distinguished. The recommended workup to exclude organic causes is blood and urine testing for substances, magnetic resonance imaging, computed tomography, electroencephalography, and psychological testing with structured clinical interviews. One last thing is worth saying out loud to her, because it is true and because nobody has said it yet: this is diagnosed in 1-2% of the general population, equally in men and women, and it usually starts before the age of 25 — the earliest reported onset is 16. She is 22. She is not going mad, and she is very far from the only one.
Educational reference
The explanation and decisive case findings were checked against the source below.
Open the clinical referenceEditorial policy and correctionsFor education and entertainment only. This fictional case is not medical advice and does not replace supervised clinical training, diagnosis, or treatment.
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