1. Dichotomy or continuum
Learning goals
- Should psychological disease be on a dichotomous or continuous scale?
- What are the pros and cons of a dichotomous or continuous scale?
- How does psychosis develop?
- What’s the difference between the DSMIV and DSMV? How is psychosis diagnosed with it?
[Leede-Smith]
When auditory hallucinations have a negative content, a high frequency, an emotional valence and
cause anxiety or depression, there’s a need for care. When they are in combination with a psychotic
illness, there’s a maladaptive coping strategy. The general population has auditory hallucinations too
(5-28%).
- Biopsychosocial model
Bio Psycho Social
Triggers: Cogn. Mechanisms: Triggers:
* substance use * inhibitory control * Trauma
* epilepsy * spatial integration * Life events
* dementia * intrusive thoughts * Hassles
Background: * memory * Stress
* Schizotypy * language processes Background:
* Hypnogogic/ Emotional background: * Loneliness
hypnopompic * Affective disregulation * Reduced stimulation
* Delusions
* Coping
* Metacognition
* Voice characteristics
Mechanisms cause the maintenance of the hallucinations, triggers cause the onset of them.
Sensitization = every psychosis makes you more vulnerable for new psychosis.
Auditory verbal hallucinations are most common in schizophrenia and schizoaffective disorder, but
also in bipolar disorder, substance intoxication and organic dementias.
Childhood: prenatal complications and delayed developmental milestones are related to the
development of psychosis. Persistence of auditory hallucinations is associated with severe
pathology.
Adolescence: rapid changes hormones and brain -> initiation mental health symptoms, stress
associated with changes = trigger -> schizophrenia (when predisposed)
The non-clinical population have hallucinations that are little or no distress in daily life and
controllable (60%). Psychosis could be on a continuum, from normal healthy experiences to
pathological/psychotic experiences.
- The same mechanisms in clinical and non-clinical population?
, - Non-clinical population has auditory verbal hallucinations only after certain conditions, with less
emotional valence, other cognitive capacities, more control over hallucinations and less often
intrusive thoughts or traumatic experiences causing the hallucinations. Less distress for daily life.
+ Both clinical and non-clinical population has the same localization, number of voices and
loudness of voice.
Disorder Symptoms Risk Factors Brain Comorbidity
abnormality
- Auditory Verbal - Persistence of - Dopaminergic -
Hallucinations hallucinations dysfunction (=>
- Distress pos. symptoms)
- Other mental - Structural
health problems abnormality (=>
- Help seeking neg. symptoms)
behavior
Schizophrenia:
- Positive symptoms: hallucinations and delusions
- Negative symptoms: withdrawal, poverty of speech, flattened affect
3 Clusters: positive, negative and cognitive. Develops in late adolescence mostly. More likely to have
experienced life-events (pre – or perinatal). Earlier behavioral disturbances before clinical symptoms.
Slow emergence of brain abnormalities, especially frontal. Combination of genetic predisposition and
environment.
[Hyman]
DSMIV and DSMV
Pros and cons DSMIV:
- Lack of adequately replicated information, genetic/non-genetic risk factors, anatomical
substrates or any objective medical test for mental disorders.
+ Cross-cultural similarities of major disorders and evidence for heritability (twin studies)
+ Used to select treatments that are often effective
- Overlap in medicine for several disorders
- Categorical, while many disorders are dimensional, continuous with the normal state. There is a
expression pattern of risk gene variants, associated with non-genetic factors, that cause more or less
symptoms in greater or lesser severity. Examples of dimensional disorders: depression,
schizophrenia, autism, personality disorders & ADHD.
- Many patients are grouped as not other specified (NOS), there’s a disparity of criteria and clinical
presence
- There is a lot of comorbidity, those illnesses may have the same underlying risk genes and
disease processes. This might be caused by errors in lumping and splitting symptoms in to
syndromes.
- No evident biomarkers for the mental disorders