Delusions: a symptom approach
Delusions: a symptom approach
Defining & examples
Many delusionary claims are unfalsifiable - so how do we know that they are incorrect?
Though we don't
they are false, they are considered delusions if they are bizarre
"My son was replaced by a CPR dummy"
"Gigi Hadid is in love with me"/ delusional jealousy
their own delusions?
Behaviour is often not entirely aligned with the delusion
actions are not as would be expected in accordance with belief in delusions
which are misidentified as beliefs
Does a delusion necessarily mean an
Could also be about the
"I am Jesus"
A false belief based on incorrect inference about external realities which is held firmly despite contesting beliefs and lack of proof
Religious beliefs don't count as are accepted by an entire culture
changes with time and place:
Rokeach: the 3 Christs of Ypsilanti
3 patients who each believed they are Jesus
Fought with one another violently
Eventually explained away the others
Other Anomalous Experiences leading to Delusions
Mirrored-self misidentification: person in the mirror seen as a stranger
caused by face processing deficit in brain
Tinnitus ear illness -> 'Bees in the head' delusion
patient has disrupted recognition systems (Temporal Lobe) which lead to anomalous feelings of familiarity
says Anomalous experiences are enough to explain delusions
But things like Tinnitus are very common, and not everyone develops 'Bees in the head' delusion?
Deja Vu also common but most people don't delusionally believe that they have
lived the same life more than once
The delusion that you are already dead
Works as a protective factor against the fear of the inevitable: death - Terror Management Theory
If fear of death is the motivator, why not believe you are invincible/ immortal?
Perhaps motivation is actually fear of unknown after death, not death itself? Or perhaps death and immortality beliefs achieve the same goal so it makes no difference?
Global disruption to brain pathways regarding sensory experiences
The delusion that a close loved one (like your Mother) is actually an imposter
This delusion is caused by maladaptive brain processes
Problem with face recognition due to dysfunction in the
Visual Cortex and/or Limbic System
: extreme emotional response leading to high suspiscion
Anomalous experience of faces
Skin response indicates lower familiarity in psychotic group when looking at familiar faces.
Brain surgery in treatment of epilepsy later developed feelings that his Mother wasn't really herself
But not full belief in delusion? So other factor at play -
The delusion protects against negative emotional responses or resolves inner conflicts
resolution of ambivalence (conflicting love and hate) towards person
delusion is an attempt to cover forbidden incestuous desires "I want to sleep with her and it's OK because she isn't really my Mother"
Also believed this about aunt, brother and uncle - too much incest to be true?
A bit Freudian... unfalsifiable
Delusion also occurs in relation to pets/ inanimate objects - incest not the root of these.
The delusion that people known to the patient follow them in disguise
Impaired brain functioning
After a stroke, patient claimed that two acquaintances were following her
higher emotional response to unfamiliar faces
"My father follows me in disguise" provides comfort if Father is in fact dead -
Fails to explain why patients with this delusion might believe that the misidentified strangers have
Motivational vs Deficit
as they protect the person from a negative experience
reducing discomfort or confusion
Help make sense of a disturbing experience
A coping mechanism which can neutralise/explain negative or strange experiences via a delusion
Unfalsifiable - if we can't test it then does it have any use?
Some argue that these views are obselete
"tired and outdated"
But perhaps M accounts for specific delusions may be plausible/ justifiable?
as they create a false sense of reality
A product of dysfunctional thinking/ brain processes
The anomalous experience
the locus of the pathology is in the
neuroscience of the experience
present in the general population, but they are mild and not impairing
Psychotic symptoms are simply the extreme end of the spectrum
Cognitive Behavioural Therapy
Therapist presents alternative hypotheses to delusions: collaboration and consideration of evidence to support alternatives
Reasoning Biases reveal cognitive dysfunction so CBT justified
Evidence that antipsychotics effective in managing delusions
Side effects can be difficult so alternatives are preferable
Weight gain, sexual dysfunction, type 2 diabetes and others :
Weigh up evidence and evaluate it. Changing beliefs according to said evidence.
based in evidence
Why is this belief adopted and maintained despite implausibility?
Irrational thinking hypothesis: Delusional people are
Some delusions suggest that patients are
hear buzzing which sounds like bees (tinnitus) so concretely believe that bees are present
'Jumping to conclusions'
evidence that psychosis patients rely too heavily on evidence and don't evaluate evidence rationally, compared to healthy population
Even true when reward offered for accuracy
expectation and occurrence discrepancy
delusions associated with aberrant prediction error signalling - higher response to
Suggests increased salience of ordinary, everyday experiences which could lead to feelings of unfamiliarity
1: Disruption in brain causes anomalous sensory experiences which trigger prediction error signals
2: Excess PES increase salience of experience and cause over-active response
Symptom Approach & DSM
A sign or feature indicating a disease or disorder
Delusions are a symptom of multiple different disorders in the DSM-5
Whereas, Syndrome Approach = a condition or disease characterised by symptoms
Positive symptom: additional element not present in the healthy population
Diagnoses may include
Brief Psychotic Disorder
Substance or Medication Induced Psychosis
Brain injury etc
Characterisation of syndromes by symptoms is controversial
Symptoms may have
different underlying causes and effects
so... might not provide accurate diagnoses
patients with hallucinations are better at self-monitoring than those with just delusions
delusions are the belief and hallucinations are the experience, they can occur independently and together