Ch 7 Memory the retention of information over time o Our memories are surprisingly good in some situations and surprisingly bad in others o The paradox of memory The same mechanisms that serve us well most of the time can cause us problems in others Amazing feats in memory A J and hyperthymestic syndrome Kim Peek the real Rain Man Rajan and pi But memory is also surprisingly malleable Memory illusion our brains will often go beyond the available information to make sense of the world Generally adaptive but makes us prone to errors o Reconstructive Memory when remembering we actively reconstruct memories not passively reproduce them Most believe memory operates like a video camera o Three systems of memory Sensory short term and long term Differ in terms of span and duration Moves from sensory to STM to LTM and then back to STM o Sensory Memory brief storage of perceptual information before it s passed to shortterm memory Each sense has its own form of memory Iconic visual lasts only 1 second echoic auditory can last 5 10 seconds o Short term Memory memory system that retains information for limited durations Very brief in duration 5 20 seconds We can lose information in our STM due to two different processes Decay vs Interference The span of STM in adults is 7 or 2 pieces of information Can extend our STM span by using chunking Rehearsal repearting information in STM extends the duration of it Maintenance rehearsal is simply repeating the stimuli in the same form Elaborative rehearsal links stimuli to each other in a meaningful way Elaborative is usually more effective consistent with levels of processing model Three levels visual phonological sound related and semantic meaningrelated Visual is the most shallow phonological somewhat less and semantic the deepest o Long term Memory relatively enduring store of information Includes facts experiences and skills we ve developed over lifetime Differs from STM in many ways Types of LTM Explicit memory is the process of recalling information intentionally Divided into o o Semantic memory knowledge of facts o Episodic memory events in our lives Implicit memory is recalling information that we don t remember deliberately o Unlocking our front door o Tying our shoelaces o Includes habituation classical conditioning and other forms of learning o Procedural memory refers to motor skills and habits Riding on a bicycle touch typing o Priming is our ability to identify a stimulus more easily or more quickly after we ve encountered similar stimuli Three Processes of Memory Encoding is getting information into memory To encode it we must first attend to it Most events we experience are never encoded in the first place The next in line effect and memory for common objects Mnemonics are learning aid that enhances recall o Please Excuse My Dear Aunt Sally o Every Good Boy Does Fine o While applicable to almost anything they depend on existing knowledge store o Pegword method uses rhyming o Method of loci place imagery o Keyword method language learning reminder Storage o How we store our experiences in memory depends on our interpretations and expectations of them o Schemas are organized knowledge structure or mental model that we ve stored in memory What happens when you go to a restaurant Schemas give us frames of reference and allow us to interpret new situations Useful but tend to oversimplify information Strong example of why the paradox of memory exists Retrieval o Many types of forgetting are failures of retrieval o Using retrieval cues can help to access information in long term memory o Measuring memory makes use of the 3 Rs Recall generating previously remembered information Recognition selecting previously remembered information from an array of options Relearning how much more quickly we reacquire something learned before o Ebbinghaus and Relearning Examined relearning Memorized nonsense sequences of three letters BND GRF Savings Demonstrates information is still there need practice o Tip of the tongue retrieval failure where we are sure we know the answer but can t come up with it o When people believe that something is on the tip of their tongues they re frequently right o Encoding Specificity more likely to remember something when the conditions present at the time we encoded it are also present at retrieval Context dependent learning superior retrieval when the external context of the original memories matches the retrieval context State dependent learning superior retrieval of memories when the organism in the same physiological or psychological state as it was during encoding Can extend to mood dependent learning and the retrospective bias Storage is keeping information in memory Retrieval is the reactivation or reconstruction of information from memory Predicting what we remember o Primacy effect shows up in remembering stimuli that were presented first LTM o Recency effect shows up in remembering stimuli that were presented most recently STM o Also more likely to remember stimuli that are odd or distinctive Types of Interference o Retroactive happens when learning new information hampers earlier learning o Proactive happens when earlier learning gets in the way of new learning o Both are more likely to occur when old and new stimuli are similar Neural basis of memory o Elusive engram the physical trace of memory in the brain o Taught rats to run in mazes o Lesioned parts of the brain o Still had some memory of the maze Biology of Memory o Long term potentiation LTP is the gradual strengthening of the connections among meurons from repetitive stimulation Plays a key role in learning Hippocampus plays a key role in forming memories o There is not however an engram Memories are diffusely stored Neurons that fire together wire together o LTP and Glutamate Enhances release in the synapse enhanced learning Amnesia o Two types o Anterograde cannot lay down new memories o Retrograde cannot retrieve old memories H M o Had severe epileptic seizures o Removed large parts of his temporal lobes including both hippocampi o Developed amnesia anterograde no new memories and retrograde 11 years prior to surgery o Oblivious to having surgery stuck in time Emotional Memory o The amygdala and hippocampus interact to give us emotional memories Amygdala helps recall emotions associated with fearful events Hippocampus helps us recall the events themselves o What happens when the amygdala is damaged Can remember facts about the experience Cannot