HALLUCINATIONS. Miren Edelstein PSYC182 December 10 th, 2014

Transcription

1 HALLUCINATIONS Miren Edelstein PSYC182 December 10 th, 2014

2 What are hallucinations? Sensations and perceptions that appear real but are created by your mind (absence of an external stimulus) Stigma in western society Not always associated with pathology Types of hallucinations Can occur in any sensory modality: visual, auditory, olfactory, tactile, gustatory

3 Visual hallucinations Elementary (simple) Lights, colors, shapes or patterns Complex Images of people, scenes or things that look unmistakably real

4 Auditory hallucinations (paracusia) Elementary (simple) Tones, hissing, whistling etc. Tinnitus Complex Voices, music or other sounds

5 Some causes of hallucinations 1) Sensory deprivation 2) Sleep related phenomena 3) Bereavement/grief 4) Drug use 5) Neurological conditions 6) Mental illnesses

6 1) Sensory deprivation Brain fills in details that aren t actually there Anechoic chambers/sensory deprivation rooms with no light/sound can bring on hallucinations within 15 minutes Sensory deprivation tank (float tank) sessions for sale Drug-like experiences without the drugs

7 2) Sleep related phenomena Sleep deprivation can lead to hallucinations Hypnagogic/hypnopompic hallucinations Occur just as you are falling asleep or waking Associated with sleep paralysis and narcolepsy Exploding head syndrome

8 3) Bereavement/Grief Grief from the loss of a loved one Hallucinations of the deceased not uncommon Mass hallucinations after large scale traumatic events Ghost sightings Half of widow/widowers felt presence of deceased 1/3 reported actually seeing, hearing and talking to deceased Perception has yet to catch up with knowledge of their loved one s passing Not usually pathological May be a coping mechanism to deal with loss

9 4) Drug use Hallucinogens & Dissociatives LSD Mushrooms (psilocybin) Peyote (mescaline) Ayahuasca (DMT) Anesthesia (ketamine) PCP (Ecstasy) MDMA Dextromethorphan Salvia divinorum Hallucinogen Persisting Perception Disorder (HPPD) Drug withdrawal Alcohol (delirium tremens), barbituates, benzodiazepines

10 5) Neurological Conditions Migraines Alice in Wonderland Syndrome Temporal Lobe Epilepsy Charles Bonnet Syndrome Musical Ear Syndrome Palinopsia

11 5) Neurological Conditions Migraines with auras Less than 20% of migraines Auras occur 5-20 minutes before migraine onset Blind spots/scintillating scotomas Blindness in half your visual field or in one or both eyes Zig-zag patterns Prickling/tingling sensation on skin

12 5) Neurological Conditions Alice in Wonderland Syndrome (Todd Syndrome) Common in childhood, normal optical system Perceptual distortions of size or shape of objects/body parts Micropsia and macropsia Associated with migraine auras

13 5) Neurological Conditions Temporal Lobe Epilepsy (TLE) Often have auras (commonly olfactory/ gustatory) preceding a seizure Déjà vu or jamais vu Distortions of object shape/size Macropsia/micropsia Hyperreligious delusions/ hallucinations

14 5) Neurological Conditions Charles Bonnet Syndrome Complex visual only hallucinations in individuals with partial or severe blindness Mentally healthy and realize what they see isn t real Hallucinate patterns, people or objects that are usually smaller than normal

15 5) Neurological Conditions Musical Ear Syndrome Mentally healthy individuals with hearing loss Musical hallucinations

16 5) Neurological Conditions Palinopsia Recurrence of a visual image after the stimulus has been removed Visual after image/perseveration

17 6) Mental illnesses Paranoid schizophrenia Auditory hallucinations common Dissociative identity disorder Auditory hallucinations common Bipolar disorder Hallucinations can occur in either manic or depressive phases PTSD Nearly 40% of combat veterans hear voices Borderline personality disorder 20-50% have auditory hallucinations