this presentation contains disorders of memory in relation to psychiatry

1. DISORDERS OF MEMORY
PRESENTER-Dr.SIVA ANOOP
MD Psychiatry Resident
Institute of Mental Health,Hyderabad.
DISORDERS OF MEMORY

2. Biology of memory
• Memory is the glue that binds mental life, the scaffolding for personal
history.
• Memory is a special case of the general biological phenomenon of
neural plasticity. Neurons can show history-dependent activity by
responding differently as a function of prior input, and this plasticity of
nerve cells and synapses is the basis of memory.

3. • A major source of information about memory has come from extended
study of the marine mollusk Aplysia californica.
• Aplysia is capable of associative learning (including classic
conditioning and operant conditioning) and nonassociative learning
(habituation and sensitization).

4. • In vertebrates, memory cannot be studied quite as directly as in the
simple nervous system of Aplysia.
• Long-term memory in vertebrates is thought to be based on
morphological growth and change, including increases in synaptic
strength along particular pathways.

5. Long-Term Potentiation
• The phenomenon of LTP candidate mechanism for mammalian
longterm memory.
LTP
observed when a postsynaptic neuron is persistently depolarized
after a high-frequency burst of presynaptic neural firing.
LTP
has number of properties that make it suitable as a physiological
substrate of memory.

6. • It is established quickly and then lasts for a long time.
• It is associative, in that it depends on the co-occurrence of presynaptic
activity and postsynaptic depolarization.
• It occurs only at potentiated synapses, not all synapses terminating on
the postsynaptic cell.
• LTP occurs prominently in the hippocampus, a structure important for
memory.

8. • Reference-Ganong’s physiology

9. Reference-Ganong’s physiology

10. Method for elucidating molecular mechanisms of memory
introducing specific mutations into the genome
By deleting a single gene, mice can be produced with specific
receptors or cell signaling molecules inactivated or altered.
• Genetic manipulations introduced reversibly in the adult are
particularly advantageous in that specific molecular changes can be
induced in developmentally normal animals.

11. Associative Learning
• The study of classical conditioning has provided insight into the
biology of memory.
• Classical conditioning has been especially well studied in rabbits using
a tone as the conditioned stimulus and an air puff to the eye (which
automatically elicits a blink response) as the unconditioned stimulus.
• Repeated pairings of the tone and the air puff lead to a conditioned
response, in that the tone alone elicits an eye blink.

12. • Reversible lesions of the deep nuclei of the cerebellum eliminate the
conditioned response without affecting the unconditioned response.
• These lesions also prevent initial learning from occurring, and, when
the lesion is reversed,rabbits learn normally. Thus, the cerebellum
contains essential circuitry for the learned association.
• The relevant plasticity appears to be distributed between the
cerebellar cortex and the deep nuclei.

13. Reference-Journal of Neurophysiology

14. CORTICAL ORGANIZATION OF MEMORY
• Karl Lashley, after a number of trials in rats to know the locus of
memory ,after removing different areas of brain found that the
deficit was proportional to the amount of cortex removed.
• The deficit did not seem to depend on the particular location of
cortical damage.
• Lashley concluded that the memory resulting from maze
learning was not localized in any one part of the brain but
instead was distributed equivalently over the entire cortex.
• Maze learning in rats depends on different types of information,
including visual,tactile, spatial, and olfactory information.

15. Reference-Wideman, N. (1999). Constructing scientific psychology: Karl Lashley’s Mind-Brain Debates. Cambridge
University Press.

16. Immediate memory and Working memory
• Specific visual processing areas in the dorsal and ventral streams,together
with areas in prefrontal cortex, register the immediate experience of
perceptual processing.
• The results of perceptual processing are first available as immediate
memory.
• Immediate memory the amount of information that can be held in mind
(like a telephone number) so that it is available for immediate use.
• Immediate memory can be extended in time by rehearsing or otherwise
manipulating the information, in which case what is stored is now said to be
in working memory.

18. MEMORY AND AMNESIA
• The hallmark of amnesia is a loss of new learning ability that extends
across all sensory modalities and stimulus domains
Anterograde amnesia
• Can be explained by understanding the role of brain structures critical
for acquiring information about facts and events.
• Typically,anterograde amnesia occurs together with retrograde
amnesia, a loss of knowledge that was acquired before the onset of
amnesia.
• Retrograde deficits often have a temporal gradient, following a
principle known as Ribot law; deficits are most severe for information
that was most recently learned.

19. Types of Amnesias
•Psychogenic
Amnesias
•Dissociative
•Katathymic
• Organic Amnesias
• Acute brain disease
• Subacute coarsebrain
disease
• Chroniccoarsebrain
disease
Other Amnesias

20. • A patient with a presentation of amnesia exhibits severe memory
deficits in the context of preservation of other cognitive
functions,including language comprehension and production,
reasoning, attention,immediate memory, personality, and social skills.
• The selectivity of the memory deficit in these cases implies that
intellectual and perceptual functions of the brain are separated from
the capacity to maintain in memory the records that ordinarily result
from engaging in intellectual and perceptual work.

21. Case findings
HM became amnesic in 1953, at 27 years of age, when he sustained a bilateral resection of the
medial temporal lobe to relieve severe epilepsy. The removal included approximately one-half
of the hippocampus, the amygdala, and most of the neighboring entorhinal and perirhinal
cortices. After the surgery, HM’s seizure condition was much improved, but he
experienced profound forgetfulness. His intellectual functions were generally preserved. For
example, HM exhibited normal immediate memory, and he could maintain his attention
during conversations. After an interruption, however, HM could not remember what had
recently occurred. HM’s dense amnesia was permanent and debilitating. In HM’s words, he felt
as if he were just waking from a dream, because he had no recollection of what had just taken
place.

23. • Cumulative study of the resulting memory impairment eventually
identified the medial temporal structures and connections that are
crucial for memory.
• These include the hippocampus—which includes the dentate gyrus,
hippocampal fields CA1,CA2, and CA3, and the subiculum—and also
the adjacent cortical regions including the entorhinal, perirhinal, and
parahippocampal cortices.

24. Case findings
• EP was diagnosed with herpes simplex encephalitis at 72 years of age.
Damage to the medial temporal lobe region produced a persistent and
profound amnesia. During testing sessions, EP is cordial and talks freely
about his life experiences, but he relies exclusively on stories from his
childhood and early adulthood. He will repeat the same story many times.
Strikingly his performance on tests of recognition memory is no better than
would result from guessing. Tests involving facts about his life and
autobiographical experiences revealed poor memory for the time leading up
to his illness but normal memory for his childhood .EP also has good spatial
knowledge about the town in which he lived as a child, but he has been
unable to learn the layout of the neighborhood where he lived only after he
became amnesic .

25. Types of Memory
• Declarative memory—
• Non –Declarative memory—

26. • Sensory memory
• Short term memory
• Long term memory
• Auto-biographical memory
• Flashbulb memories
• Episodic memory
• Semantic memory

27. Distortions of memory or paramnesia
• Distortions of recall
• Distortions of
recognition

28. Distortions of recall

31. Distortions of recognition

32. • False reconnaissance is defined as false recognition or
misidentification and it can occur in organic psychoses and in acute
and chronic schizophrenia.
• It may be positive when the patient recognises strangers as their
friends and relatives.
• In confusional states and acute schizophrenia, at most, a few people
are positively misidentified.
• In negative misidentification ,the patient insists that friends and
relatives are not whom they say they are and that they are strangers in
disguise.

33. Ganser State
• Vorbeigehen (‘to pass by’) or approximate answers.
• Clouding of consciousness with disorientation.
• ‘Hysterical’ stigmata.
• Recent history of head injury, typhus or severe emotional stress.
• ‘Hallucinations’, auditory and visual

34. • According to Enoch and Trethowan,there are four features in Ganser’s
syndrome:
A. approximate answers
B. clouding of consciousness
C. somatic conversion features
D. pseudohallucinations (not always present).

35. Hyperamnesia
• Exaggerated registration, retention and recall.
• Opposite of amnesia and paramnesia.
• Flashback memories

36. Recovered Memory and False Memory
Syndrome
• The recovery of additional memories after apparent psychogenic
amnesia for a long time.
• Recovered memory has been particularly associated with the return
of memory for childhood sexual abuse.
• False Memory syndrome patients are typically females and are
subjected to sexual abuse by their parents during their childhood.

37. Perseveration
• Defined as a response that was appropriate to a first stimulus being
given inappropriately to a second, different stimulus.
• Usually occurs in association with disturbance of memory
• Sign of organic brain disease, perhaps the only pathognomonic sign in
psychiatry.
• It occurs with clouding of consciousness and is particularly useful in
distinguishing this from dissociative abnormalities.
• This may be demonstrated verbally or in motor activity.

38. MEMORY DISTURBANCE AND
ELECTROCONVULSIVE THERAPY
• Memory disturbance associated with impaired learning ability,
defective retrieval and apparent loss of memory stores.
• Retrograde amnesia is more common than anterograde amnesia.
• According to Weeks et. al,ECT does not produce lasting impairment
when used in everyday clinical circumstances.
• According to Fraser, the memory loss that follows ECT is minimal and
can be detected for only a few hours after treatment.

39. MEMORY IMPAIRMENT IN SCHIZOPHRENIA
• Deficits in long-term memory.
• Impaired retrieval in both recall and recognition.
• Impaired short-term memory.
• Impaired working memory and semantic memory, but procedural or
implicit memory is intact.

40. Temporal lobe disorder
• Disorder of memory in TLD includes the hippocampal defects of
diminished storage and accelerated forgetting;
• Déjà vu and Jamais vu also occur.
• There may be altered states of consciousness such as a fugue, with
impaired registration.

41. Clinical assessment of Memory
• Ask the patient to listen carefully while you tell him a name and address, then ask for
its immediate reproduction.
• Record his answer verbatim, and repeat if necessary when the first response is
unsatisfactory.
• Test retrieval 3–5 minutes later after interposing other cognitive tests, and again
record the answer verbatim.
• Test ability to repeat a sentence immediately after a single hearing.
• The sentence should be appropriate to the patient’s intellectual level as in the
following examples from the Stanford–Binet series.

42. • For a 13 yr old: ‘The aeroplane made a careful landing in the space
which had been prepared for it’.
• Average adult: ‘The red-headed woodpeckers made a terrible fuss as
they tried to drive the young away from the nest.’
• Superior adult: ‘At the end of the week the newspaper published a
complete account of the experiences of the great explorer.’
• With patients having limited ability or who are hard to be sure of
cooperation a technique which is similar to that of Irving et al. can be
used.
• Addenbrooke’s Cognitive examination-III can be used to assess
memory in dementia patients

43. ACE-III

45. • Valid assesment of patient’s recent memory requires that any question
asked by the examiner should be verified from another source other
than the patient.
• ORIENTATION-
Orientation to Time and Place is an example of recent memory
• Disorientation recent memory deficit.
• Immediate recall(Short-term memory)Digit span test
• Recent Incidental Memoryability to recall events occurred during
the hours or days before the evaluation.

46. • New Learning-ability to actively learn new material,a process that
requires establishing new memories.
• Four Unrelated Words-Brown,honesty,tulip,eyedropper.
• Verbal story for immediate or delayed recall
• Visual Memory(Hidden objects)
• Remote Memory-ability to recall personal and social events from
remote past.

47. Take home Message…….
• Memory is of clinical interest because disorders of memory and complaints
about memory are common in neurological and psychiatric illness.
• Personalities are shaped by nondeclarative memories in the form of
numerous habits and conditioned responses.
• Memory impairments can occur in schizophrenia and major depression
alongwith organic disorders.
• Memory is distributed and localized in the cerebral cortex.
• The hallmark of amnesia is a loss of new learning ability that extends across
all sensory modalities and stimulus domains.
• ECT does not cause more than a temporary disturbance in memory.

48. References-
• Kaplan and Saddock’s Comprehensive Textbook of Psychiatry-10th edition.
• Lishman’s Organic Psychiatry-Textbook of Neuropsychiatry-4th edition
• Fishs Clinical Psychopathology-3rd edition
• Sims’ Symptoms in the Mind-Textbook of Descriptive Psychopathology-5th
edition.
• Sturb and black-Mental Status Examination -1st edition.
• Ganong’s Physiology-23rd edition.
• Journal of Neurophysiology