The document discusses various types of perceptual abnormalities including sensory distortions, deceptions, and illusions. It describes abnormalities in different senses such as vision, hearing, touch, and others. Sensory distortions can involve changes in intensity, color, shape, size, motion, or location of perceived objects. Illusions can be completion, affective, or pareidolic in nature. Hallucinations are false perceptions without an external stimulus and can occur in any sensory modality. Organic causes as well as psychiatric conditions can produce different perceptual abnormalities. The document provides examples and details of many specific perceptual disorders.

1. Moderator-Dr.Ravichandra Karkal
Dr.Samin Sameed
Post-graduate
Department of Psychiatry
Yenepoya University

2.  The process of transferring physical
stimulation into psychological information;
mental process by which sensory stimuli are
brought to awareness.

3. Abnormal
perception
Sensory
deceptions
Sensory
distortions

4.  Sensory Distortion- real perceptual object
which is perceived in a distorted way
 Sensory Deception- new perception that
may occur that may or may not be in
response to external stimuli
 Disorders in the experience of time

5. Color,intensity
Shape and size
Motion/general
quality
location
uniqueness

6.  Changes in Intensity - hyperesthesia -
lowering of physiological threshold.
 Eg.Hyperacusis
Seen in
 anxiety
 depressive disorder,
 Hangover from alcohol
 Migraine
 hypochondria cal personalities

7.  Hypoaesthesia
 Eg - Hypoacusis
 Seen in
 Delirium
 Depression
 Attention deficit disorder

8. •Hyperaesthesia

9. •Complete absence of color

10.  Visual perception – toxic drugs
Xanthopsia
Chloropsia
Erythropsia
Derealization- Everything looks unreal and
strange
Mania- looks perfect and beautiful

11.  Change in perceived shape of an object
 Retinal disease
 Disorders of accommodation
 Temporal and Parietal Lobe Lesions
 Poisoning with Atropine and Hyoscine
 SCHIZOPHRENIA

12.  Micropsia – a visual disorder in which the
patient sees objects
o Smaller than they really are
o Farther away than they really are
 Macropsia –
 Seeing objects larger than they really are

15.  Experience of retreat of subjects into the
distance without any change in space -
porropsia
 Edema of the retina
 Partial Paralysis of accomodation
 Diseases affecting the nerves controlling
accommodation

17. teleopsia
•Object appearing far
away
pelopsia
•Object appearing
nearer than it should

19.  Psychopathological point of view
 Physical- Determined by physical events
 Personal- Personal judgement of passage
of time
Mania- Time passes quickly
Depression- Time passes slowly
Acute Schizophrenia- personal time goes in fits
and starts
Acute organic states (temporal disorientation)

20. illusion
hallucination
Misinterpre
tations of
stimuli
from
external
object
Perceptions
without
external
stimulus

21. Stimuli
from
perceived
object
Mental
image
False
perception

22.  Completion Illusion – These depends on
inattention,misreading words in newspapers
 Affect Illusion- These arise in the context of
particular mood state
 Pareidolia – vivid illusions without the
patient making any effort ; result of
excessive fantasy thinking and a vivid visual
imagery.

25.  False perception which is not a sensory
distortion or misinterpretation but which
occurs at the same time as real perception.
 Essential criteria for an operational
definition
1. Percept like experience in the absence of
an external stimuli
2. Percept like stimuli which has full force
and impact of real perception
3. Percept like experience which is unwilled,
occurs spontaneously and cannot be
readily controlled by percipient.

26.  Intense emotions
 Suggestion
 Disorders of sense organs
 Sensory deprivation
 Disorders of CNS
 Psychiatric disorders

27.  depressed patients -delusions of guilt;
hallucination - disjointed or short phrases
 continuous persistent hallucinatory voices in
severe depression ? Schizophrenia /physical
disease.

28.  Normal subjects can be persuaded to
hallucinate .
 By hypnosis or brief task motivation
instructions.

29.  Hallucinatory voices -in ear disease
 Visual hallucination - eye diseases ,disorders
of the CNS
 Peripheral lesions -sense organs -
hallucinations in organic states

30.  incoming stimuli reduced to minimum -
normal subject -hallucinate after few hours
 changing visual hallucinations ,repetitive
phrases
 BLACK PATCH DISEASE delirium following
cataract extraction in the aged result of
sensory deprivation and mild senile brain
changes

31.  Lesions of diencephalons and cortex can
produce hallucination that are not only visual
but can be auditory.

32.  Hearing
 Vision
 Smell
 Taste
 Touch
 Pain and deep sensation
 Vestibular sensations
 The sense of presence

34.  Hearing (auditors) may be elementary or
unformed.
 Elementary – noises, bells or undifferentiated
whispers ; in organic states
 Partly organized- music
 Completely organized- hallucinatory voices-
schizophrenia- persecutory in nature
 Severe depression „voices‟ heard , less well
formed than schizophrenia

35. Imperative hallucination
 Voices sometimes act upon individuals and
give instructions.
 may or may not act upon them
Auditory hallucinations
 Adverse
 Neutral
 Helpful
 Incomprehensible nonsense
 Neologism

36.  Thought echo - hearing one‟s own thoughts
being spoken loud, voice may come from
inside or outside the head.
i. GEDANKENLAUTWERDEN- thoughts spoken
at the same time or before they are
occurring.
ii. ECHO DE LA PENSES- thoughts are spoken
just after they occurred.
 Running commentary hallucinations are
usually abusive.

38.  Elementary- flashes of light
 Partly organized- patterns
 Completely organized- people,
animals,objects.
Scenic hallucinations- like a cinema
common in delirium
in psychiatric disorders with epilepsy.

39.  Patients with visual and auditory
hallucinations co occur as a whole
 Temporal lobe epilepsy
 Late onset of schizophrenia (protracted)

40.  Visual Hallucinations - organic states
+clouding of consciousness >functional
psychoses
 Small animals –delirium
 rare -schizophrenia
 Occasionally without any psychopathology
CHARLES BONNET SYNDROME

42. Seen in
 Schizophrenia
 Organic states like temporal lobe epilepsy
 Depression (uncommon)
PADRE PIO PHENOMENON- religious people
can smell around certain saints

44. Seen in
 Schizophrenia
 Organic states
Depressed patient often describes loss of taste.

46.  Formication- animals crawling over the
body;
in organic states
 Cocaine bug – formication + delusion of
persecution - cocaine psychosis
 Sexual Hallucinations- acute and chronic
schizophrenia

47.  Classified into 3 types
1. Superficial
2. Kinesthetic
3. Visceral

48.  Thermic
 Haptic
 Hygric
 Paraesthetic

49.  affects muscles and joints
 Patient feels limbs twisted pulled or moved
 schizophrenia
 Organic states - alcohol intoxication
benzodiazepine withdrawal

50.  Visceral hallucinations (SIMS 2003).
 Twisting and tearing pains
 Very bizarre complaints- organs ripped out ,
flesh ripped from his body
 chronic schizophrenia

51.  Organic states
 Schizophrenia
 Conversion disorder
 Normal people – fervently religious

52.  mental image ,clear and vivid,lack the
substantiality of perceptions
 Full consciousness
 subjective space
 Definite outlines
 Constancy retained,insight preserved
 Relevant to emotions, needs and actions
 Depends on the observer for existence
Hysterical
Attention seeking personalities

53.  Functional hallucinations : auditory
stimulus causes the hallucination, both
experienced
 Chronic schizophrenia
 Reflex Hallucination : a stimulus in one
sense modality produces hallucination in
another. Morbid variety of synaesthesia.

54.  Extracampine hallucination : Hallucinations
that is outside the limits of the sensory field.
o Seen in healthy people as hypnagogic
hallucination
o Schizophrenia
o Organic conditions- epilepsy

56.  Autoscopy (phantom mirror image) –
experience of seeing oneself and knowing
that it is oneself
VH+Kinesthetic +somatic sensation.
 Normal subjects- emotionally disturbed,
tired and exhausted
 depressed
 Hysteria
 Schizophrenia

57.  Acute and sub acute delirious states
 Epilepsy
 Focal lesions in parieto occipital region
 Drug addiction
 Chronic alcoholism
NEGATIVE AUTOSCOPY
INTERNAL AUTOSCOPY

58.  Occur when the subject is falling asleep
during drowsiness
 Are discontinuous
 Appears to force themselves on the subject
 Do not form part of an experience in which
the subject participates unlike DREAM
 Commonest is auditory.
 geometrical designs , abstract shapes , faces
, figures or scenes from nature
 EEG shows alpha rhythm

59.  Occurs when the subject is waking up
 Hallucinations persisting from sleep when the
eyes are open
 More in narcolepsy.

60.  Occurs in any sensory modality and may
occur in various neurological or psychiatric
disorders
 Depends on
i. General condition of the brain
ii. Recent experiences
iii. Psychodynamic factors
iv. Effect of local lesion

61.  Stimulation of visual projection areas in the
walls of the calacrine fissure causes
perception of flashes of light as does
stimulation or irritation of optic radiation.
 Lesions of optic tract and lateral geniculate
bodies.
 Spontaneous V H – sensory defect
 Complex scene hallucination – stimulation of
posterior part of temporal lobe.

63. Almost exclusively the result of lesion which
produces sensory defect
PHANTOM LIMB
 Most common organic somatic hallucination
 95% of amputation after 6 yrs of age
 Pt feels he sees the limb from which in fact
he is not receiving any sensations either
because limb has been amputated or sensory
pathway destroyed.

65.  Most phantom limbs are produced by
peripheral and central disorders.
 Occasionally it develops from lesion of
peripheral nerve or the medulla or spinal
cord.
 Thalamoparietal lesions have phantom third
arm or leg.
 Correspond to the previous image of the
limb.

66.  Whistling , buzzing, drumming and even bells
heard by patients with middle ear disease or
internal disease
 Caused by epileptic foci and space occupying
lesions in the temporal lobes

67.  Occurs most often in temporal lobe epilepsy
ass with salivation and chewing and sniffing
 Stimulating the depths of the sylvian fissure
around the transverse temporal gyri.
OLFACTORY HALLUCINATIONS
 temporal lobe epilepsy.

68.  These are multisensory hallucinations but
they do not include somatic sensations,
which is to be expected because the somatic
sensory area is separated from the temporal
lobe by sylvian fissure.

69.  Hyperschemazia –
percieved
magnifications of
body parts
 When part of the
body feels larger
than the normal
 ORGANIC CAUSES
o Brown Sequard
Syndrome
o PVD, MS, thrombosis
of PICA
 NON ORGANIC
CAUSES
o Hypochondriasis
o Conversion disorder
o Depersonalization

70.  Aschemazia- perception of body parts as
absent
 Hyposchemazia – Body parts as diminished
 Paraschemazia – distorted of body image as a
feeling that body parts are distorted or
twisted from rest of the body.
 Hemisomatognosia- Unilateral lack of body
image in which the person behaves as if one
side of body is missing

71.  Anosgnosia- „denial of illness‟ –Rt hemisphere
strokes denied their knowledge early after
stroke and refused to admit to any weakness
in their left arm
 Somatoparaphrenia- delusional beliefs about
the body, distorted, inanimate , severed, or
in any other ways abnormal.

72.  Fish‟s Clinical Psychopathology- Patricia
Casey and Brendan Kelly
 SIMS‟ Symptoms in the Mind- Femi Oyebode
 Synopsis Of Psychiatry-Benjamin James
Sadock, Virginia Alcott Saddock

73. Compared to the brilliance of the evening sun, reflecting on the
beautiful sea, we humans are NOTHING, but SHADOWS…

74.  “You see, but you do not observe. The
distinction is clear.” – Sherlock Holmes