DISORDERS OF MEMORY / memory / learning.pptx

Disorder of memory

1. DISORDERS OF MEMORY

2. Memory is a general term for a mental process that allows the individual to store information for later recall . Memory Strub & black ; mental status examination in neurology; 4 th edition

3. MODELS OF MEMORY PROCESSING

4. Atkinson and shiffrin’s information-processing theory Memory starts with a sensory input from environment . This input is held for a very brief period of time in sensory register associated with sensory channel . Information that is attended to and recognized in sensory register is passed on to short term memory ( STM ) . Here it is held for 20-30 sec Some information reaching short term memory is processes by being rehearsed a lot of time or may be linked up with other information already stored may then be passed to long term memory ( LTM )

5. In 1974 Baddeley and Hitch proposed a working memory model which replaced the concept of general short term memory with specific, working memory. This consists of three basic stores central executive phonological loop visuo -spatial sketchpad. In 2000 this model was expanded with the episodic buffer. Central executive located in the prefrontal cortex . It channels information to : the phonological loop, the visuo -spatial sketchpad, and the episodic buffer. phonological loop and visuospatial system are rehersal system for retaining visual and spatial & language aspects of stimulus . Working memory model – baddeley and hitch

6. The episodic buffer is dedicated to linking information across domains to form integrated units of visual, spatial, and verbal information and chronological ordering. The working memory model explains many practical observations, such as why it is easier to do two different tasks (one verbal and one visual) than two similar tasks (e.g., two visual).  

7. They suggested that the more deeply information is processed; the more likely it is to be retained (Baron, 2005). They argued that all of these processes would lead to some long-term learning, but that the amount of learning depended on the type of processing, with "deep" processing in terms of meaning leading to much better retention than "shallow" processing. Maintenance rehearsal might keep material available, but would not enhance long-term learning. Levels of processing model- Craik and Lockharts

8. Encoding / registration : process of receiving sensory input and and transforming into a form / code that can be stored. Storage/ retention : It is a process of actually putting a information into memory Retrieval : it is the capacity to access stored information from memory by recognition or recall . Recall is the effortful retrieval of stored information into consciousness at a chosen moment. Eg what is capital of india ? Requires recall function . Recognition is the retrieval of stored information that depends on the identification of items previously learned and is based on either remembering (effortful recollection) or knowing (familiarity based recollection ) eg which of the following is the capital of india ? Delhi , mumbai , lucknow . Tests recognition function . Stages of memory process

9. 1. SENSORY MEMORY 2. SHORT TERM MEMORY / WORKING MEMORY 3. LONG TERM MEMORY BASED ON DURATION

10. It is primarily a selecting and recording system that comes into play in the early phase of memory formation via which perceptions ( auditory, visual, touch, taste etc.) enter the memory network. Visual stimulus is registered as an exact replica called Iconic image lasting up to 1 sec . Auditory stimuli is registered as an Echoic image lasting up to 4-5 sec in sensory register . We pay “ attention and recognize” some of the information in sensory register , this attended to information is converted to short term memory . Sensory memory / sensory register

11. It is the capacity for holding a small amount of information in mind in an active, readily available state for a short period of time. Short term memory can withhold information received from sensory register up to about 30 seconds. For example, if you saw a person walking a dog and a few seconds later heard a dog bark you would not be surprised since you would identify the likely source of the sound from sensory (visual) memory that had been processed and encoded in short-term (working) memory. Short term memory/ working memory

12. It provides lasting retention of information and skills from minutes to a lifetime and has a limitless capacity. Long term memory

13. Encompasses all the information that we can consciously describe or report i.e. the person is conscious that they are remembering . Areas of brain involved : hippocampus and medial temporal lobe . It is of two types 1. semantic memory 2. episodic memory Declarative / explicit / relational memory

14. Semantic memory is the memory of abstract facts . It is the memory that make use of language possible i.e. it consist of knowledge about what words mean , how are they related to each other and about the rules of using them in communication and thinking . Eg . What is the capital of india . Semantic memory

15. Consist of long term memories of specific thing that happened to us at particular time and place. for example, your wedding day. It is characterised by a general recall of the event, an interpretation of the event and a recall of a few specific details. Episodic memory/ autobiographical memory

16. Refers to skills, habits or other manifestation of learning that can be expressed without an awareness of what has been learned. It is heterogeneous collection of unconscious memory abilities. Subtypes – 1. Procedural 2. Simple classical Conditioning 3. Priming Implicit / Skill memory

17. There is no active awareness that memory is being searched in undertaking the particular skill. For example, information necessary to perform skilled motor activities like driving a car. This type of memory is processed in straitum . Procedural

18. It is a non conscious form of human memory concerned with perceptual identification of words and objects . Eg . If a person reads list of words including the word “table” , and if later asked to complete the word “tab” the probability that he/she will answer table is greater than if they are not primed . Area of the brain involved : neocortex . Priming

19. Simple Classical Conditioning is another type of non-declarative memory that generally occurs in the presence of conscious awareness of conditioned stimulus (CS) and unconditioned stimulus (UCS) but can occur without awareness also . This type of memory is dependent on the amygdala for its emotional responses and the cerebellum for the motor responses . Simple classical Conditioning

20. The TOT phenomenon indicates that information is organized in long-term memorv . Suppose you are trying to retrieve a person's name hut you cannot quite remember it; the name is on the "tip of your tongue," but you just cannot recall it. In TOT state we try to retrieve it from our long term memory so we tend to retrieve word which are sound like target word start from the same letter as target word Contained same no. of syllables as target word has meaning similar to target word . Eg . While trying to write the child was” abandoned” by parents , we wrote child was “ absconded ‘ by parents . Tip of tongue phenomenon

21. Forgetting refers to the apparent loss of information already learned and stored in long term memory. Intereference theory Forgetting is a result of some memories interfering with others. Proactive interference : Old memories interfere with ability to remember new memories. Retroactive interference : New memories interfere with ability to remember old memories. Intereference is stronger when material is similar. Forgetting

22. The three are distinguished by the time interval between presentation of the stimuli and retrieval. Immediate memory Recent memory Remote memory Clinical classification

23. patient should have sustained attention  inattentive, distractible patients cannot perform optimally on such tests. Patients who cannot perform optimally on these tests - Patients in an acute confusional state With severe psychotic disorder (usually have impaired attention) deaf, aphasic patients anxious, depressed, or grossly inattentive may reflect memory impairment caused by these processes alone . Things to keep in mind before clinical memory evaluation

24. Immediate memory is used to recall a memory trace after an interval of a few seconds. It is usually tested by digit repetition test . Here the patient repeats the numbers as read to him/her by the examiner. DIRECTIONS : The digits are presented in normal tone of voice at a rate of one digit per second. Do not to group digits either in pairs (e.g., 2-6, 5-9) or in sequence that could serve as an aid to repetition(e.g., in telephone number form, 3768439). Numbers are presented randomly without natural sequences. Begin with two number sequences and continue until the patient fails to repeat all the numbers correctly. Immediate memory

25. Scoring Normally a patient of average intelligence can accurately repeat five to seven digits without difficulty. In a non retarded patient without obvious aphasia, inability to repeat more than five digits indicates defective attention.

26. Recent memory is the patient's capacity to remember current, day-to-day events (e.g., the current date, the doctor's name, what was eaten for breakfast, or recent news events). recent memory is the ability to learn new material and to retrieve that material after an interval of minutes, hours, or days. Orientation to place and time are actually measures of recent memory, as they test the patient’s ability to learn these continually changing facts. Recent memory

27. Direction Orientation or recent memory is tested in a sequence by asking the patient firstly about his name, age, date of birth; secondly the place where he is currently residing in terms of name of the place, kind of place and floor; city, state, country, his home address and lastly testing the time domain comprising of date, day, time and season of the year. Scoring : Usually normal people score perfectly right in all these domains. Those who are not high school educated makes plus minus 2 days error in recalling the date and those who are above high school educated makes an error of one day plus minus in recalling the day

28. These test evaluate the patient’s ability to recall personal and historic events. Remote Memory

29. Instructions: Tell the patient, “ I am going to tell you four words that I would like you to remember. In a few minutes, I will ask you to recall these words ”. To ensure that the patient has heard, understood, and initially retained the four words, have him or her to repeat the words immediately and to correct any errors. Then he is asked to recall the words at 5, 10 and 30 minutes. To eliminate possible mental rehearsal, interference should be used between presentation and recall of words. New learning ability

30. Set 1 छाता, फूल, घडी, तस्वीर, पैंसिल Set 2 मछली, लैंप, रुपया, ताज, खिलैना Scoring: Normal persons accurately recall 3-4 words after a 10-minute delay. In some, after being reminded of the correct words i.e., by verbal cues, whether he/she recognizes the appropriate word from the series of words and improve their performance after 10 and 30 minutes may be seen, but patients with dementia cannot improve even on subsequent trials.  

31. Memory disorders can be broadly classified into– 1. Amnesias (loss of memory) 2. Paraamnesias (distortions of memory) 3. Hyperamnesias Memory disorders

32. Amnesia

33. FREUD used the concept of repression to account for childhood amnesia. He said that we are unable to retrieve childhood memories because they are associated with the forbidden, guilt arousing sexual and aggressive urges. According to SAHACTHEL there are different ways young children and older people encode & store information . Adult store info in language form while Young and without language people encode info in the form of images and feelings , which are difficult to retrieve . Childhood amnesia

34. Freud’s used concept of repression to account for dream amnesia . He considered dreams to be expression of forbidden sexual and aggressive urges. These urges have a capacity to generate guilt , anxiety feelings hence are difficult to retrieve . Another concept “ STATE DEPENDENT MEMORY “ If people encode and store info in a particular emotional or drugged state they may not be able to retrieve info in another emotional state . Eg alcoholic who were under the influence of alcohol when they hid a bottle , then forget where they put it when sober but remember when drunk again . In dreaming brain seems to be in a special state different from that of waking again . Dream amnesia

35. It is the inability to recall specific painful memories and is believed to occur due to defense mechanism of repression. There is no loss of personal identity as occurs in dissociative amnesia . Catathymic amnesia/ motivational forgetting

36. This is a sudden amnesia that occurs during periods of extreme trauma and may be concerned about the stressful or traumatic life events that may last for hours or even days The amnesia will be for personal identity such as name, address and history as well as for personal events, while at the same time the ability to perform complex behaviors is maintained (Casey and Kelly,2007). Dissociation may be associated with a fugue or wandering state in which the subject travels to another town or country, and is often found wandering and lost. There is no demonstrable anterograde amnesia. . Dissociative amnesia

37. a way of protecting oneself from the guilt or anxiety that can result from intense, intolerable life situations and conflicts . The amnesia will be for personal identity such as name, address and history as well as for personal events. Amnesic episode can last for weeks, months, or years but the information stored during the amnesic episode is not retrieveable i.e memory gap present . Defensive amnesia

38. ORGANIC AMNESIAS Referred to as true amnesia and can affect different functions of memory. There can be impairment of registration, retention, retrieval or recall, or recognition

39. Anterograde amnesia Impairment of registration / encoding In delirium , epilepsy Retrograde amnesia impairment in retention Acute head injury Confabulation impairment in retrieval Impairment of recognition Alzheimers / schizophrenia

40. Confabulation is the falsification of memory occurring in clear consciousness in association with organic pathology. It manifests itself as the filling in gaps in memory by imagined or untrue experiences . Confabulation Embaressed type Fantastic type Patient tries to fill in gaps in the memory as a result of awareness of a deficit . These are real memories displaced in time . Gaps in the memory are filled by details exceeding the need of memory impairment More common Include fantastic details that never happened .

41. Amnestic syndromes

42. It is an irreversible residual syndrome, caused by severe thiamine deficiency and occurring after incomplete recovery from a Wernicke encephalopathy, predominantly in the context of alcohol abuse . The severe memory impairment is characteristic , primarily to declarative memory (Arts et al., 2017). Within this declarative memory domain, both episodic memory and semantic memory are affected. In each of these sub-domains, the anterograde memory processes are more severely affected than retrograde processes The individual may also be distinguished by flattened affect , apathy, lack of illness insight, and possibly by fantastic confabulations in the early stage ( Gasquoine , 2017). There is preserved attention, personality, social functioning, STM, and nondeclarative memory. Korsakoff‘s syndrome

43. Global amnesia is characterized by a relatively circumscribed deficit in LTM for new information. There is inability to learn new material. It appears that transient global amnesia may be caused by temporary bilateral dysfunction of medial temporal lobe structures, including the hippocampus, entorrhinal cortex, and parahippocampal gyrus . (Fisher, 1982). I t occurs in middle aged and elderly men more commonly than women (Fisher and Adams, 1964). The condition,can emerge in times of severe stress, pain, or emotion, and has been attributed to migraine, epilepsy, drug use, hypoglycaemia , stroke, and neoplasms but is still not clearly understood. These patients normally improve spontaneously, within a few hours. Clinically can be assessed by recall and recognition tests that require retrieval of recently learned information. Transient global amnesia

44. This is distortion of memory . This can occur in normal subjects due to the process of normal forgetting or due to proactive and retroactive interference from newly acquired material and is also seen in persons suffering from emotional problems or other organic states. ` It can be divided into Distortions of recall & Distortions of recognition Paraamnesia

45. DISTORTIONS OF RECALL

46. It refers to the unintentional distortion of memory that occurs when it is filtered through a person's current emotional, experiential and cognitive state . Eg . depressive illness people describe all past experiences in negative terms due to the impact of their current mood. So a depressed person will highlight their failures while ignoring and/or forgetting about their successes. Retrospective falsification

47. Retrospective delusions are found in some patients with psychoses who backdate their delusions in spite of the clear evidence that the illness is of recent origin . Eg . A patient will say that he has always been persecuted . Retrospective delusions

48. These are recollection of events that did not occur but which the individual subsequently believes that it did take place . It entails a person to construct a memory around a event that did not take place . False memory

49. It is a recollection that is partly true and partly false. Person only recalls part of true memory because entirety of the true memory is too painfull to recall . Eg an individual recall that a childhood sexual abuse was done by the neigbour because it is too painfull to recall that sexual abuse was done by their own brother. Screen memory

50. Confabulation that occurs in those without organic brain pathology such as personality disorder of antisocial or hysterical type. It is also known as pathological lying, mythomania or morbid lying. Patient will describe various major events and traumas and make grandios claims which are often present at the time of personal crisis. Pseudologia fantastica

51. A variant of pathological lying . In this an individual present to the hospital with bogus illness , complex medical histories and often multiple surgical scars. Munchausen’s Syndrome

52. Patient produces facticious illness in someone else, generally child . Munchausen’s Syndrome by proxy

53. Ganser in 1898 described set of symptoms which include approximate answers ( Vorbeireden ). The approximate answers suggest that the patient understands the question but appears to deliberately avoiding correct answers. Eg . when asked how many eyes does the cat have . Patient will answer 3 . In gansers syndrome there is clouding of consciousness present while in similar condition of approximate answers is found in those consciously feigning illness as seen in malingring consciousness in clear . Ganser Syndrome

54. Experience of not remembering that one is remembering . Eg a person writes a witty passage and does nor realise that they are quoting from some passage that they have seen elsewhere rather than writing something original . Cryptoamnesia

55. DISTORTIONS OF RECOGNITION

56. Déjà vu It comprises the feeling of having experienced a current event in the past, although it has no basis in fact. Jamais vous is the knowledge that an event has been experienced before but is not presently associated with the appropriate feelings of familiarity. Déjà entendu is the feeling of auditory recognition . Déjà pense , a new thought recognized as having previously occurred. It is related to déjàvu , being different only in the modality of experience. These experiences occur occasionally in normal persons but they may become excessive in temporal lobe lesions.

57. This may occur in confusion psychosis and in acute and chronic schizophrenia. Misidentification may be positive and negative. Positive misidentification The patient recognizes strangers as his friends and relatives even though there is no physical resemblance. Some patients assert that all of the people whom they meet are doubles of real people. Negative misidentification The patient insist that friends and relatives are not whom they say they are and that the are strangers in disguise . Misidentification

58. Fregoli syndrome In fregoli syndrome hyperidentification takes place. The patient identifies a familiar person (usually his persecutor) in various strangers, who are therefore fundamentally the same individual. Capgras Syndrome The essential feature of this syndrome is hypoidentification . Patients insists that a particular person (or persons), usually somebody with whom the patients is emotionally linked, is not the person he claims to be but is really a double. The commonest cause of capgras syndrome is schizophrenia and less common causes include involutional depression and hysteria.   MIS-IDENTIFICATION SYNDROMES

59. The opposite of amnesia and paramnesia . There is exaggerated registration, retention and recall. Flashbulb memories are unusually vivid, detailed and long Flashbacks that are associated with the cognitive and emotional experiences of a traumatic event such as an accident. Eg 9/ 11 bombing witnesses It is regarded as one of the characteristic symptoms of post-traumatic stress disorder but is also associated with substance misuse disorders and emotional events Eidetic images are exceptionally vivid memory images and occurs immediately after any type of perception. More common in childen than adults . Hyperamnesia

60. Fish’s clinical psychopathology ; 4 th edition Sims symptoms in the mind ; 6 th edition Morgan and king ; introduction to psychology Strub & black ; the mental status examination in neurology Refrences