Lecture 5: Memory

Lecture 5: Memory

1. Memory processes and systems

   • Memory is a thing
     • Record of our past experiences
   • Memory as an operation
     • 1. Encoding
     • 2. Storage
     • 3. Retrieval
   • Modal Model of Memory
     • Sensory memory -> STM -> LTM

2. Sensory memory

   • -Briefest memory -Based on direct sensory stimulation
   • Iconic memory
     • Visual stimulus captured at the retinas that persists beyond the stimulus
     • Lasts about 250ms
     • Icon
       • Long-lasting mental representation
   • Measuring capacity of sensory memory
     • Whole report condition
       • People were asked to remember as many letters as possible (after they disappeared)
     • Partial report condition
       • Participants are cued about which part of the array they should report 
   • Object files
     • Mental representations of an object
   • Change blindness
     • Lack of accurate detail being encoded in iconic memory

3. Short-term memory

   • Stores small amounts of information for a brief period of time (~20s)
   • Decay
     • Passive loss of information over time
   • Brown-Peterson Paradigm
     • Results show that memory performance declines very quickly when rehearsal is not possible
     • Initial results suggested memory loss due to decay but later interpretations suggested interference
   • Interference
     • Information interferes with or in some way hinders the retrieval of other information
     • Retroactive
       • New information gets in the way of old memory
     • Proactive
       • Old information gets in the way of new learning
   • 7+/- 2 vs. 4 items
   • Chunking
     • Organizing information into meaningful units
   • How is information coded?
     • Code
       • How information is stored mentally
       • Auditory
         • Errors based on sounds of the letter
       • Visuospatial
       • Semantic
         • STM is encoded semantically to SOME extent
         • Release from interference

4. Working memory

   • Temporary storage and manipulation of information for complex tasks 
   • Phonological loop
     • Holds verbal and vocal information
     • Capacity of about 2 seconds 
     • Word length effect
       • People remember shorter words easier
     • Word similarity effect
       • A list of words that sound similar will be more difficult to perform (people will add similar words that weren't on the list)
   • Visuospatial sketchpad
     • Holds visual and spatial information
     • Orientation task
       • Physical orientation = mental orientation
   • Central executive
     • Set of processes that do manipulations 
     • Working memory occurs in PFC 
     • Inhibits prepotent responses (i.e. Stroop)
     • Delayed response task
       • Neurons in the PFC are tuned to maintain information during the delay for a specific location
     • Neural mind-reading

Images and files in the map