Psych 202 Lecture February 19 2015 Introduction to Memory Processes Four Models of Memory o 1 Information processing approach memory is a process similar to a computer three basic processes encoding storage retrieval o 2 Parallel Distributed Processing Model memory is distributed across a wide network of interconnected neurons location in various location in the brain when activated the network works simultaneously parallel manner to process information o 3 Levels of Processing Approach memory depends on the degree or depth of processing occurring shallow processing leads to little memory deeper processing leads to greater memory processing is how much you think about something recall versus recognition o 4 Stage Model the flow of information through the memory system figure 6 8 from textbook Sensory input Sensory memory unattended information is lost after about 3 seconds Short term memory unrehearsed information is lost Long term memory some information may be lost over time capable of encoding and retrieving short term memory 30 seconds or less unless renewed information goes from LTM to STM to be retrieved We only remember stimulation that enters our sensory memory processes if it receives attention in conscious experiencing of one or more sensory modalities is held and maintained in STM working memory Iconic vs echoic memory Short term memory STM aka working memory three part working memory visuospatial sketchpad where things are phonological rehearsal loop language based rehearsal of info central executive managing working memory as a whole requires attention and has limited capacity stores 7 2 noticed items for up to 30 seconds longer with rote or maintenance rehearsal chunking increases STM capacityfacilitates encoding and transfer to LTM facilitates consolidation of information in STM and LTM Primacy effect and recency effect you remember best what happens first or last Long Term Memory LTM Our enduring recollection of recent and remote past explicit without conscious recall Procedural memory motor and cognitive skills Primingenhanced identification of objects or words and implicit memory with conscious recall semantic facts and general knowledge episodic personally experienced events Examples of measuring explicit memory recollection of facts events consciously retrieved in response to direct questions Recall vs recognition tests like Name the 7 dwarves from snow white recall 67 accuracy vs selection of names from a list 86 accuracy Elaborative rehearsal needed to create meaningful chunks and hierarchies must go beyond rote rehearsal to deeper processing meaning and self relevance in elaborative rehearsal you create a rich semantic network Organization of explicit LTM semantic networks of related concepts in semantic networks the activation of one concept mental grouping of items helps you remember other items ex red fire engine truck vehicle bus transportation What does this mean for memory demands of testing studying don t focus on rote maintenance rehearsal Instead consolidate knowledge by organizing it into semantic networks encoded meaning utilize chunking and hierarchies or concept maps to assist the elaborative process of memory Sleep plays an active role in memory consolidation sleep increased hippocampal activity interaction between hippocampus and frontal lobe facilitates interaction between interaction of hippocampus with frontal lobe Hippocampus is critical as an index for LTM storage without hippocampus you can retrieve old LTMs but can t create new LTMs only STM Memory Loss A Case Study virus infection destroyed part of his brain EP video this would be in a 6 foot rat he repeated the story several times unknowingly temporal lobes affected by the virus Anterograde amnesia inability to transfer from STM to LTM Retrograde amnesia inability to retrieve information from before a particular date Consolidation memories becoming more stable in the brain over time Biological bases of memory neuronal and Synaptic Changes repeated stimulation of a synapse can strengthen the synapse by causing the dendrites to grow more spines ability of a neuron to release its neurotransmitters can be increased or decreased Greenough rats who exercised vs learned found neural connections increased blood supply increased glial cells increased actual brain changes with learning while controlling for motor activity Long term potentiation LTP a process whereby communication across the synapse between neurons strengthens connection making further communication easier NMDA receptor a receptor site on the hippocampus that influences the flow of information between neurons by controlling the initiation of LTP NMDA receptors have glutamates bind to them and excitation occurs Information is sometimes available in memory even if we can t access it existence of forgetting has never been proved Encoding specificity principle the idea that a retrieval cue can serve as an effective reminder when it helps recreate the specific way in which information was initially encoded o 1 State dependent retrieval information to be better recalled when the person is in the same stated during encoding and retrieval if learned in a certain context state then easier to retrieve true with substances but also emotion o 2 Transfer appropriate processing memory is likely to transfer from one situation to another when the encoding context of the situations match Alcohol myopia and memory cognitive nearsightedness relatively low BAC 06 alcohol decreases reasoning and concentration failure to process all cues severe alcohol abuse Korsakov s or memory cognitive impairment Reconstructive nature of LTM the past is malleable and flexible constantly changing as our recollection reinterprets and re explains what has happened