Feb 13 Memory 1

• Memory functions include: routines and habits, the sense of self, social functions, and problem-solving
• Memory is not a single entity
• There are three stages of memory: encoding, storage, and retrieval
• 3 Stages of Memory:

  1. Encoding: learning new information - forming new “memory trace” as a neural code
  2. Storage: retaining encoded memory trace/ neural code
  3. Retrieval: activating a memory trace via a cue (probe for that memory) for a purpose
• Memory is categorized into sensory memory, short-term memory, and long-term memory
• Sensory memory includes:

  1. Iconic Memory
  2. Echoic Memory
  3. Haptic Memory
  4. Gustatory Memory
  5. Olfactory Memory
• Short-term memory has a limited time capacity of about 20 to 30 seconds and a limited capacity known as "magical number seven plus or minus two"
• Working memory involves retention and manipulation of information not in our environment in conscious awareness
• Short-term memory stores include the phonological loop, visuospatial sketchpad, and episodic buffer
• Long-term memory consists of implicit and explicit memory
• Encoding explicit memories involves processes like the spacing effect, active rehearsal, and levels of processing theory
• Mnemonics are used to help encode information by linking new information to prior knowledge
• Causes of forgetting include decay theory and interference theory, with proactive and retroactive interference effects on memory
• Strategies to improve memory retention include reviewing work regularly, focusing on important material, and linking new information to existing knowledge
• Clive Wearing Case: episodic memory was impaired but other forms of memory remained intact
• Explicit Memory is further divided into 2:

  1. Semantic Memory: facts and general knowledge
  2. Episodic Memory: personal experiences and specific events in time
• What Does Memory Do?

  • Routines and habits; like brushing teeth, Riding bike
  • The sense of self; like the facts you have about yourself developed from your experiences
  • Social functions; like you might recall a funny story to connect with a person
  • Solving problems; like you recall similar experience to solve a current problem
• Encoding: When a memory trace is formed as a hippocampal-cortical activity pattern
• Storage Consolidation: When a memory is transformed into a stable cortical pattern
• • Retrieval: when a cue (Part of a memory trace) is triggers pattern completion of the brain pattern
• Positive Afterimage: a visual memory that represents the perceived image in the same colors

  • Helpful for seeing things smoothly 
  • E.g.; see 75 frames/second, movies are 24 frames/second, but view movies as a smooth event due to afterimage filling in holes 
• Negative Afterimage: a visual memory is the (color) inverse of the perceived image 

  • Slightly longer than positive afterimage (few seconds)
• Chunking Strategy: grouping items together in a meaningful way so more information to be represented at one time
• Phonological Store: Passive store for verbal information 

  “The inner ear” 
• Articulatory Control Loop: Active rehearsal of verbal information 

  • “The inner voice” a specialized role in language 
  • Used to convert written material into sounds (reading); a specialized role in language 
• The Visuospatial Sketchpad 

  • The Visual Cache: information about visual features 
  • The Inner Scribe: information about spatial location, movement and sequences
• • Neuroimaging Evidence: Different areas of the brain are active for visual and verbal short term memory tasks 
• Double Dissociation in Neuropsychological Cases: 

  • Patient ELD: has problems recalling visual-spatial but not verbal material in the short term 
  • Patient PV: has problems recalling verbal but not visual material in the short term
• Episodic Buffer: Integrates information from short- and long-term memory
• Ebbinghaus: he learned nonsense syllables, tested memory at various intervals, and examined what was retained (forgotten)

  • Created over 2000 cards of nonsense syllables 
  • Learned sets of the syllables under strict testing conditions

  -Read the syllables without any inflection 

  -Read them at a consistently fast pace: 2.5 items per second 

  -He did nothing else while running these experiments 

  
  

  (Did this to remove confounds )
• The Spacing Effect: information is retained more effectively in long-term memory when study sessions are spaced out over time with intervals in between, rather than being concentrated in a short period of time (crammed)

  • Forgetting is reduced when learning is spread over time 
  • Repeated information is more valuable 
• Active Rehearsal: The Testing Effect

  • Participants studied a text passage 
  • Between group manipulation (studied more; practice test) 
  • Both groups took final test 
  • Retrieving memories after test leads to deeper encoding
• Shallow Processing: Focus on sensory information 
• 2 Levels of Processing:

  1. Shallow Processing: Focus on sensory information 

  2. Deep Processing: integrate higher-level knowledge (things we know) with learned information)

  • Memory is stronger with deep processing, more elaborate memory traces
• Learn new words in a new language , memorizing vocabulary words and their translations is shallow processing, using the words in sentences is deep processing
• What Causes Forgetting 

  • Decay Theory: Memories are lost over time due to disuse 

  -Like a muscle you don’t use, a memory gets weaker 

  • Interference Theory: Interference is responsible for much of forgetting 

  -Encoded memories are labile and need to be consolidated into stable long-term memories

  -During pre-consolidation period, memories are susceptible to disruption and effects of interfering information
• Proactive Interference (‘forward in time’): prior information interferes with encoding a new memory 

  • E.g.; Trouble learning a new phone number because your old number keeps popping up in your memory
• Retroactive Interference (‘backward in time’): newly learned information overwrites or interferes with a prior encoded memory 

  • E.g.; Trouble remembering an older password after you formed a new password
• Similarity Effect: the more alike something is to what is already learned, the more it will mingle and interfere with memory