Disorders of Memory

1. Disorders of Memory

2. Introduction • Memory: cognitive ability to encode, store, and retrieve information • What happens to information after it has been perceived is usually discussed under memory • Some information is forgottenalmost immediately whereas some might be retained for seconds, hours, years or even a lifetime Disorders of Memory

3. Basic Components of Memory • Sensory memory • Working memory (short term memory) • Long term memory Disorders of Memory

4. Three Stages Model of Memory Sensory Memory Encoding Attention Working Memory / STM Long Term Memory SI Retrieval Encoding Rehearsal Disorders of Memory

5. Remembering • Process of remembering • Registration • Retention • Retrieval • Recall • Most memory tests measure recall of prior events either from the persons life or from tests administered earlier Disorders of Memory

6. Remembering … • Autobiographical memory • Memories for events and issues related to oneself • Associated with the active experience of remembering • Flashbulb memories type of autobiographical memory which the person becomes aware of an emotionally arousing event Disorders of Memory

7. Memory Impairment • Amnesia • Loss of memory • Paramnesia • Distortions of memory • Hyperamnesia • Exaggerated of memory Disorders of Memory

8. Amnesia • Partial or total inability to recall past experiences and events • Origin may be organic or psychogenic • Failure to recall may also occur due to normal memory decay, i.e. unrehearsed items Disorders of Memory

9. Amnesia … • Interference from related materials • Proactive: old memories interfere with new learning hence with recall • Retroactive: new memories interfere with the retrieval of old materials Disorders of Memory

10. Organic Amnesias • Acute brain disease • Memory is poor owing to disorders of perception and attention hence failure to encode material in LTM • Acute head injury • Retrograde amnesia - events just before the injury • Anterograde amnesia - events occurring after the injury; common in accidents Disorders of Memory

11. Organic Amnesias … • Blackouts are circumscribed periods of anterograde amnesia • Experienced particularly by those who are alcohol dependent during and following bouts of drinking or acute confusion states (delirium) due to infections or epilepsy Disorders of Memory

12. Organic Amnesias … • Subacute coarse brain disease • Inability to register new memories or learn new information and inability to recall previously learned material • Memories from the remote past remain intact • Not diagnosed when there are other signs of cognitive impairment Disorders of Memory

13. Organic Amnesias … • Korsakoff’s syndrome • Thiamine deficiency or cerebrovascular disease, multiple sclerosis, transient global amnesia, head injury and electroconvulsive treatment – ECT • Chronic coarse brain disease • Loss of memory extending back into the recent past for a year or so • Ribot’s law of memory regression Disorders of Memory

14. Psychogenic Amnesias • Dissociative or hysterical amnesia • Sudden, occurs during periods of extreme trauma, can last for hours or days, commonly in prior head injury • Personal identity i.e. name, address, history; or events at the same time the ability to perform complex behaviors is maintained • Dissociation can be associated with a fugue or wandering state Disorders of Memory

15. Psychogenic Amnesias … • Katathymic amnesia or motivated forgetting • Inability to recall specific painful memories • Occur due to the defense mechanism of repression • Last for many years Disorders of Memory

16. Other Amnesias … • Anxiety amnesia • Occurs on anxious preoccupation or poor concentration in depressive illnesses or GAD • Depressive amnesia • Depressive pseudo dementia • Impaired concentration Disorders of Memory

17. Paramnesia • Distortion of recall and recognition • Occur in normal subjects due to • Process of normal forgetting • Proactive and retroactive interference from newly acquired material • People with emotional problems or organic states Disorders of Memory

18. Distortion of Recall • Retrospective falsification • Unintentional distortion of memory occurs when it is filtered through the person’s current emotional, experiential and cognitive states • i.e. description of past experiences in negative terms due to the impact of the current mood in depressive illness Disorders of Memory

19. Distortion of Recall … • False memory • Recollection of event(s) that did not occur but which an individual subsequently strongly believes did take place • Distortion of actual contraction of memories around events that never took place • Increased with age, worse in presence of organic brain disease Disorders of Memory

20. Distortion of Recall … • Screen memory • Recollection that is partially true and false • Only recalls part of the true memory because the entirely of the true memory is too painful to recall • Difficult to dissect out precisely which elements are objectively true in both therapeutic or legal settings Disorders of Memory

21. Distortion of Recall … • Confabulation • Occur in clear consciousness in association with organic pathology • Filling in of gaps in memory by imagined or untrue experiences that have no basis in facts • Embarrassed: person tries to fill in gaps as a result of awareness of a deficit • Fantastic: gaps are filled in by details exceeding the need of the memory impairment Disorders of Memory

22. Distortion of Recall … • Pseudologia fantastica or fluent plausible lying (pathological lying) • Confabulation that occurs in those without organic brain pathology i.e. antisocial personality disorder or hysterical type • Blurring of the boundary between fantasy and reality and when confronted with incontrovertible evidence they admit their lying Disorders of Memory

23. Distortion of Recall … • Munchausen’s syndrome • Variant of pathological lying in which a person presents to hospitals with bogus illnesses, complex medical histories and often multiple surgical scars • Proxy of it, a person i.e. parent produces a factious illness in somebody else generally their child • Long period of time for hospital services, diagnostic and management challenges Disorders of Memory

24. Distortion of Recall … • Vorbeireden or approximate answers • A person understand the questions but appear to be deliberately avoid the correct answer • Found in those consciously feigning illness (malingering), factitious disorder, or in acute schizophrenia Disorders of Memory

25. Distortion of Recall …. • Cryptamnesia • Experience of not remembering that one is remembering (Sims, 1997) • Not common neither associated with specific any specific psychiatry disorder • Retrospective delusions • Backdate delusions in spite of the clear evidence that the illness is of recent origin Disorders of Memory

26. Distortions of Recognition • Dejavu • Not strictly a disturbance of memory but a problem with familiarity of places and events • Comprises the feelings of having experienced a current event in the past, although it has no basis in fact • Jamaisvous • Knowledge that an event has been experienced before but is not presently associated with the appropriate feelings of familiarity Disorders of Memory

27. Distortions of Recognition … • Dejaentendu • Feeling of auditory recognition • Dejapense • New thought recognized as having previously occurred • Related to dejavu, different in modality of experience • Experience with normal people or with temporal lobe epilepsy Disorders of Memory

28. Distortions of Recognition … • False reconnaissance • False recognition or misidentification • Occur in organic psychoses, acute and chronic schizophrenia • In confusion states and acute schizophrenia at most a few people are positively misidentified, some in chronic schizophrenia can give false identity to every person they meet Disorders of Memory

29. Distortions of Recognition … • False reconnaissance … • In negative misidentification person insist that friends and relatives are not who m they say they are and that they are strangers in disguise • Some patients assert that some or all people are double of the real people whom they claim to be - Capgras syndrome • Occur in schizophrenia and dementia Disorders of Memory

30. Hyperamnesia • Exaggerated registration, retention and recall • Flashbulb memories associated with intension emotions, unusually vivid, detailed and long lasting • For example many people can recall where and what they were doing when heard sad news i.e. death • Flashback sudden intrusive memories that are associated with the cognitive and emotional experiences of a traumatic event • PTSD or substance misuse disorder, emotional events Disorders of Memory

31. References • Casey P, & Brendan K. (2007) Fish’s Clinical Psychopathology; Signs and Symptoms in Psychiatry 3rd Edition. The Royal College of Psychiatrists • Gross, R. (2010) Psychology the Science of Mind and Behaviors 6th edition; Macmillan Company • King, L.A (2008) the Science of Psychology, McGraw-Hill • Lahey, Benjamin. B (2004), Psychology an Introduction 8th Edition McGraw Hill Publisher Disorders of Memory