Four Models of Memory o Information processing approach Memory is a process It s similar to a computer recording memory 3 basic processes Encoding like typing into a computer Storage like saving what you typed in the computer Retrieval like retrieving what you typed o Parallel distributed processing model Memory is distributed across interconnected neurons in the brain When activated the network works simultaneously in a parallel manner to process information In patients with Alzheimer s as more regions of the brain are damaged their memory becomes worse although they are greatest affected by damage to the hippocampus o 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 E g when you study and all you do is read your notes you don t learn as much as if you quiz yourself as you go o Three stage memory model Sensory information lost e g forgetting the faces of some of the people you walked past on the way to class Short term info lost e g forgetting the name of someone you just met Encoding involves a meaningful representation of the memory Maintenance is when you repeat information out loud or in your head to We haven t proven that long term memory is ever permanently lost Retrieval memory is recalled and then re encoded Short term memory is also known as working memory it is information that is up and activated e g remembering what you are saying when you are talking to remember it someone We only remember information if we process it pay attention to it forgetting information can occur at each step in the process of remembering something Sensory memory o Stores a brief copy for less than 3 seconds of stimuli that register during sensory Iconic memory a transduced encoded visual snapshot or icon and lasts less Echoic memory memory of sounds seems to last for several seconds processing than 1 second Short term memory STM o Aka working memory o 3 part working memory Visuospatial sketchpad e g allows you where to find the psych lecture hall without having to think hard about where it is Phonological rehearsal loop repeating something in your head to remember it Central executive has to do with attention o The working memory of STM STM requires attention has limited capacity STM stores about 7 noticed items for up to 30 seconds unless rehearsed Chunking grouping information together to remember more It facilitates encoding and transfer to LTM consolidation of info in STM into LTM It is easiest to remember the first and last items learned known as primacy recency effects respectively Long term memory LTM o Explicit memory any memories we can talk about or consciously recall Semantic memory information and facts Episodic memory personally experienced events Recall vs recognition Recall is when you can directly remember or recall information when asked about it intentionally bringing explicit information to awareness e g listing the names of the 7 dwarves from Snow White Recognition is when you realize you know the information when you see or hear it encoding an input and matching it to a stored representation e g recognizing the names of the 7 dwarves from a list of names Encoding of Explicit LTMs Elaborative rehearsal needed to create meaningful chunks and hierarchies format Elaborative rehearsal is the act of rehearsing or repeating information so you remember it like studying for a test Hierarchies are a method of organizing information like outline You are most likely to remember information by semantic judgment items that have meaning than by rhyme or visual judgment See Craik Tulving Experiment slide Organization of Explicit LTM Semantic network the network of info in your brain the activation of one concept leads to priming of semantically related concepts making their subsequent retrieval more probable if you can t remember something the semantic network can help you recall it by first thinking of related items o Implicit memory memory you aren t consciously aware of Procedural memory motor and cognitive skills e g walking Priming enhanced identification of objects or words Sleep o Is important for memory consolidation o FMRIs show that during recall for a group that got sleep as opposed to the sleep deprived group There was increased hippocampal activity There was a stronger interaction between the hippocampus and the frontal lobe Sleep facilitated the interaction between the hippocampus and the frontal lobe The hippocampus is less centrally involved in recall later on The Hippocampus o Is critical in LTM storage and serves as an index for LTM storage o E g the case of HM who had his hippocampus and temporal lobes removed to prevent seizures memories HM was incapable of storing making new memories but still had his old o Anterograde amnesia the inability to transfer from ST to LT memory e g a person walks into a room and you don t realize that they were there 10 minutes ago o Retrograde amnesia the inability to retrieve information from before a particular date e g not knowing who or where you are because your previous memories are lost o Consolidation the process by which memories become stable in the brain how memory gels o Reconsolidation memories can become vulnerable to disruption when they are recalled requiring them to become consolidated again you remember then the memory re gels Biological bases of memory o Neuronal and synaptic changes fire together wire together idea that repeated certain neurons strengthens the synapse by causing dendrites to grow more spines the ability of a neuron to release its neurotransmitters can in decrease Our brain adapts to how it is used e g taxi drivers have larger dendritic fields reserved for special memory Greenough o The experiment in which rats were placed either in an intellectually physically stimulating environment a physically stimulating environment or an intellectually stimulating environment o The rats in physically stimulating environments increased blood supplies glial cells o The rats in intellectually stimulating environments increased cognitive activity Memories neurons synapses hippocampus o Memories strengthen the connections between neurons specifically in the o Long term potentiation LTP a process whereby communication across the synapse between neurons strengthens the connection making further communication easier o NMDA receptor a receptor site on the hippocampus that influences the flow