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Memory.pptx
- 1. Memory Presenter: Dr ShashiNegi PG1 Student, Psychiatry Department IGGMC Nagpur
- 2. Outline (Focus onPsychological Aspects of Memory) • Introduction • Physiology of Memory • Theories Of Memory • Organisation of Long Term Memory • Retrieval from Long Term Memory • Forgetting • Amnesia
- 3. Introduction • Defined As:“Encoding, Storage, and retrieval of what was learned earlier.” • Study of Memory emphasises on cognitive, or mental processes. • Based upon synaptic plasticity.
- 4. • Types ofmemory: ▫ Declarative Memory (Explicit Memory) ▫ Non Declarative Memory (Implicit Memory) (Memory for Recognition of Words)
- 5. Physiology of Memory ▫The basis of memory is synaptic plasticity Increase in response to repeated activity of the synapse leads to sensitization and long term potentiating Decrease in response to repeated activity of synapse leads to Habituation and Long Term Depression. ▫ Hippocampus which is important part for memory STM consolidation (Long term Potentiation) leads to LTM
- 6. CA1 Neuronsof Hippocampus activated by different pathway which helps in consolidation (Long Term Potentiation). Sensory input pathway to hippocampus also called preforant pathway.
- 7. Theories of Memory •Theory of General Memory Functions • Information Processing Theory • Level of Processing theory
- 8. • Theory ofGeneral Memory Functions ▫ Most agreed theory ▫ Divided in three phases Encoding: Process of receiving sensory input and transforming it into a form, or code, which can be stored. Storage: Process of putting coded information into memory. Retrieval: Process of gaining access to stored, coded information when it is needed.
- 9. • Information ProcessingTheory ▫ By Richard Atkinson and Richard Shiffirin (1968)
- 10. ▫ Sensory Registeror Memory: Storage function of sensory channel Information that is given attention is sent to Short term memory, rest is lost. ▫ Short term Memory: Information retained for up to 30 Sec, However lengths of retention depends upon multiple factors.
- 11. Glanzer andCunitz (1966) gave experiment to demonstrate features of Short Term memory. They used the technique named “Free Recall”. Subjective Experiment; List of 15 noun Three Conditions: ▫ Zero Delay ▫ 10 Sec Delay ▫ 30 Sec Delay ▫ Delay interval filled with mental activity (Counting)
- 12. Recall Dependsupon serial position of Noun Better recall in beginning called Primacy effect Better recall at end is called Recency effect Recency effect affected in Delay Interval due to interference of transfer from short term to long term memory due to Mental activity
- 13. ▫ Rehearsal: Keepingitems of information in the centre of attention. Two Types Maintenance Rehearsal: Just going over and over information to be remembered Elaborative Rehearsal: Giving Information/ material Organisation and meaning as it is rehearsed.
- 15. • Level ofprocessing Theory ▫ Given by Craik and Lockhart 1972, Elaborated by Craik and Tulving ▫ Information can be worked at different Three levels Perception: Immediate awareness of environment. Structural Level: Structural features of the Inputs are analyzed (sound, look, other details) Meaning Level: deeper Meaning of the input.
- 16. ▫ Greater theelaboration of Information more likely it is to be remembered.
- 17. Organisation of LongTerm Memory • Conscious Long Term memory is divided into Semantic and Episodic Memory. • Semantic ▫ “What words means, about the ways they are related to one another, and about the rules for using them in communication and thinking.” ▫ Stored in highly organised manner in two possible ways Logical hierarchy from general category to specific ones. Clusters of words with related meaning
- 18. • Episodic Memory ▫Memory of specific things that happened to us at a particular place and time. ▫ Less organised then semantic memory ▫ More Susceptible to be forgotten then semantic memory. • Encoding and Storing of Long Term Memory ▫ Encoding and storage are facilitated by organisation of materials to be remembered. ▫ Organisation: can be Objective i.e. from Material/ Information to be remembered or Subjective i.e. Imposed by us upon the information.
- 19. ▫ Forming Images:during Encoding can also helps in storage of Information. ▫ Constructive Process: Especially with complex information or Life events details are often modified or changed or inferences rather then exact details are stored in memory.
- 20. Retrieval From LongTerm Memory • Retrieval Cues ▫ Finding information in the organised long term memory is aided by retrieval cues ▫ More are cues for any encoded memory better are chances of its retrieval. ▫ There can be state depended memory and cues as well, e.g. Memory encoded during alcohol intoxication may only be retrieved under alcohol intoxication.
- 21. • Reconstructive Processesin retrieval Memory ▫ Unconscious modification of memory during retrieval. ▫ Seen in persons with organic memory disorders when gaps in memory are filled unconsciously by false information
- 22. Forgetting • Most ofthings we think are forgotten were never actually encoded and stored in memory. • Curve of Forgetting ▫ Curve of forgetting depends upon many factors
- 23. • Interferences ▫ Appearsto play role in problems in forming new memory ▫ Two types Retroactive interference: New information interfere in memory retrieval of old information. Proactive interference: Old information interfere in memory retrieval of new information. ▫ Exact mechanism of interference is still unclear
- 24. Amnesia • Amnesia: “ProfoundMemory deficit due to either loss of what has been stored or the inability to form new memories”. • Broad two Types: ▫ Psychological Amnesia: without any structural or molecular brain malfunction ▫ Biological Amnesia: with structural or molecular brain malfunction
- 25. • Psychological Amnesia ▫Childhood Amnesia Poor early Childhood memory. Three Hypothesis Repression of forbidden (Sexual/ Aggressive) memories that may cause anxiety or guilt if brought into awareness, Freud 1938 Difference in Encoding and storage of Information in adults vs. Children; Adults encode memory using language but children may encode memory using unknown organisation making retrieval of information difficult, Schachtel 1959
- 26. Lack ofmaturation of brain structures responsible for maturation in children so that memory is not stored properly ▫ Dream Amnesia Inability to remember all dreams had during sleep As per Freud due to repression of forbidden urges seen in dreams just like childhood amnesia. May also be due to different organising of memory in dreams in comparison to awake state. (State Dependent Memory) ▫ Defensive Amnesia Defensive repression of intense, intolerable life situations and conflicts to prevent anxiety, guilt or other negative emotions.
- 27. • Biological Amnesia ▫Transient Global Amnesia Profound memory problem with intact consciousness Acute onset and usually short period condition Both anterograde as well as retrograde amnesia Due to temporary alteration in pattern of blood flow in brain.
- 28. ▫ Substance Useand Amnesia Cannabis can cause minor problems in encoding and storage of memory. Alcohol Known to cause problems in encoding and storage of memory, can lead to gap in memory for period of heavy alcohol intoxication. Long term alcohol use can also cause difficult to treat Korsakoff Syndrome due to Thiamine deficiencies leading to anterograde amnesia.
- 29. ▫ Senile Dementia Old age onset deficit in intellectual abilities like memory, attention, judgement etc. Mostly anterograde amnesia Result of reduction of blood flow in brain. ▫ Alzheimer’s Dementia It is a type of Primary degenerative dementia Due to Acetylcholine deficiencies in brain areas Progressive mental deterioration from mild anterograde to profound anterograde and retrograde amnesia.
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