Perception Flashcards
What forms part of the clinical picture of many mental disorders?
Abnormal perceptual experiences
These experiences can manifest in various ways, affecting how patients perceive reality.
What are the five special senses involved in perceptual information?
- Vision
- Hearing
- Touch
- Taste
- Smell
These senses help the brain receive and process perceptual information.
What is the role of proprioceptors and the vestibular apparatus in perception?
They provide information about muscle, joint, and internal organ positions
This information contributes to the overall perceptual experience.
How is an external object represented internally in the brain?
By a sensory percept that combines with memory and experience
This process creates a meaningful internal percept in the conscious mind.
What distinguishes normal from abnormal perceptual experiences?
The ability to distinguish between real objects and internal imagery or fantasy
In health, individuals can recognize vivid experiences as not real.
What are the two types of abnormal perceptual experiences?
- Altered perceptions
- False perceptions
Each type presents differently in terms of perception and awareness.
What are altered perceptions?
Sensory distortions and illusions involving distorted internal perceptions of real external objects
These can affect how a person experiences reality.
What are false perceptions?
Hallucinations and pseudo-hallucinations where internal perception occurs without an external object
These can significantly impact an individual’s reality.
What are sensory distortions?
Changes in perceived intensity or quality of a real external stimulus
They are often associated with organic conditions or drug ingestion.
What is hyperacusis?
Experiencing sounds as abnormally loud
This is an example of a sensory distortion.
What is micropsia?
Perceiving objects as smaller and further away, as if looking through the wrong end of a telescope
This is another example of sensory distortion.
Fill in the blank: The majority of perceptual information is processed _______.
unconsciously
Only a minority of this information reaches conscious awareness at any one time.
What are illusions?
Altered perceptions combining a real external object with mental imagery to produce a false internal percept.
What predisposes a person to experience illusions?
Both lowered attention and heightened affect.
What are affect illusions?
Illusions occurring at times of heightened emotion, such as seeing a tree as an attacker when scared.
What are completion illusions?
Illusions based on the brain’s tendency to fill in missing parts of an object to create a meaningful percept.
What are pareidolic illusions?
Meaningful percepts produced from a poorly defined stimulus, such as seeing faces in clouds.
Define a hallucination.
‘A percept without an object’ as defined by Esquirol in 1838.
How do hallucinations differ from normal perceptions?
A true hallucination is perceived as being in external space, distinct from imagined images.
What is a pseudo-hallucination?
A hallucination that lacks characteristics of true hallucinations and is experienced as internal.
What is the only characteristic of true perceptions that true hallucinations lack?
Publicness; hallucinating patients recognize their experiences are not shared by others.
What are first-rank symptoms of auditory hallucinations in schizophrenia?
- Hearing a voice speak one’s thoughts aloud
- Hearing a voice narrating one’s actions
- Hearing two or more voices arguing
What are visual hallucinations commonly associated with?
Organic disorders of the brain, drug and alcohol intoxication and withdrawal.
What are ‘Lilliputian hallucinations’?
Visual hallucinations of miniature animals or people, characteristic of delirium tremens.
What disorders may olfactory and gustatory hallucinations occur in?
A wide range of mental disorders, including epilepsy, depressive illnesses, and schizophrenia.
What are hypnagogic hallucinations?
Transient false perceptions occurring on falling asleep.
What are hypnopompic hallucinations?
Transient false perceptions occurring on waking.
Fill in the blank: A true hallucination is perceived as _______.
being in external space.
True or False: Visual hallucinations are frequently seen in psychotic illness alone.
False.
What are pseudo-hallucinations most commonly associated with?
Visual or auditory experiences
Pseudo-hallucinations can occur in conditions like narcolepsy and affective illnesses but are often reported by healthy individuals.
Define elemental hallucinations.
Hallucinatory experiences of simple sensory elements such as flashes of light or unstructured noises
Elemental hallucinations are linked with organic states.
What are extracampine hallucinations?
False perceptions of external objects beyond the normal range of perception of the sensory organs
Explain functional hallucinations.
Hallucinations experienced simultaneously with a normal stimulus in that modality
For example, auditory hallucinations occurring when hearing the sound of air conditioning.
What are reflex hallucinations?
Hallucinations in one modality experienced after a normal stimulus in another modality
Why do patients often conceal their experiences of hallucinations and delusions?
Fear of being thought ‘mad’ and concern about the reaction of others
What is a recommended approach for asking patients about abnormal perceptions?
Use frankness, lack of embarrassment, and straightforwardness
What should an examiner say to normalize questions about psychotic symptoms?
‘Now I want to ask you about some experiences which sometimes people have but find difficult to talk about.’
What are depersonalization and derealization symptoms?
Non-specific symptoms in a variety of affective and psychotic conditions
How do many patients describe their experiences of depersonalization?
‘Like being in a play’
What question can be asked to explore auditory hallucinations?
‘Have you ever had the experience of hearing noises or voices when there was no one about to explain it?’
What should be clarified if a patient reports auditory hallucinations?
When it occurred, if the patient was fully awake, how often, and where
What is a delusion?
A delusion is a pathological belief held with absolute subjective certainty, requiring no external proof, and is personally significant.
Delusions are important symptoms in the diagnosis of major psychoses.
What are the characteristics of a delusion?
Characteristics include:
* Absolute subjective certainty
* No need for external proof
* Personal significance
* Not culturally or religiously understandable
Content of the delusion is usually demonstrably false and bizarre, but not always.
What is the difference between primary and secondary delusions?
Primary delusions arise directly from a pathological process, while secondary delusions develop in the context of another abnormality in the mental state.
Example of secondary delusion: delusions of poverty in a severely depressed patient.
What is an over-valued idea?
An over-valued idea is a non-delusional, non-obsessional abnormal belief that dominates a patient’s thinking and behavior.
The idea is acceptable and comprehensible but preoccupying.
What should be clarified when a patient reports hearing voices?
Clarify:
* Source of the sound
* Content of the voice
* Recognition of the voice
* Reference to the patient
* Examples of what was said
Understanding the context of auditory hallucinations is crucial.
What should be clarified when a patient reports seeing visions?
Clarify:
* Frequency and circumstances of the experience
* Perception type (mind’s eye or external)
* Distinctness from surroundings
This helps distinguish between different types of visual experiences.
What should be clarified regarding olfactory or taste hallucinations?
Clarify details surrounding any positive response to distinguish:
* Olfactory hallucinations (abnormal odor experiences)
* Delusions of being malodorous
Distinguishing these experiences is important for diagnosis.
What are over-valued ideas?
Over-valued ideas may have a variety of contents in different disorders
Examples include concern over physical appearance in dysmorphophobia, concern over weight and body shape in anorexia nervosa, and concern over personal rights in paranoid personality disorder.
What should professional staff avoid when dealing with a deluded patient?
Colluding in the delusional belief system
Doctors should not engage in arguments about the truth of the delusion, as delusions cannot be rationalized away.
How should a doctor communicate with a deluded patient regarding their symptoms?
Make clear that the delusional symptom is a symptom of mental ill health
It is important to acknowledge the delusion as real and significant to the patient.
What changes occur in delusional ideas during an illness episode?
Delusions vary in detail and intensity
Initially, there may be vague feelings of being spied upon, which become more detailed and supported by ‘evidence’ as the delusion evolves.
What is the goal of treatment for delusions?
To fade the importance of the delusion and help the person appreciate it as false
Some may still regard it as true but view it as less significant.
What is a good initial question to ask a patient about their worries?
‘Do you have any particular worries preying on your mind at the moment?’
This question allows patients to discuss concerns they may have been hesitant to mention.
What should a doctor ask to differentiate normal self-consciousness from referential delusions?
‘Do you ever feel that people are watching you or paying attention to what you are doing?’
The doctor should seek elaboration of the sensation and examples of its occurrence.
What question can help identify referential delusions related to media?
‘When you watch television or read the newspapers, do you ever feel that the stories refer to you directly?’
The patient should be invited to elaborate on any positive responses.
What are persecutory delusions?
Beliefs that people are trying to harm the individual
These are common features of psychotic illness and can be confused with paranoid personality traits.
What potential confusion may arise with persecutory delusions?
Confusion with paranoid personality traits and genuine fears
This confusion can occur particularly in the context of the patient’s lifestyle.
