memory

• Karl Lashley (1920s) taught rats how to run mazes and lesioned different parts of their brains to see if they forgot how to find their way. No matter where he removed brain tissue, the rats retained at least some memory of the maze. Support for equipotentiality hypothesis: Other areas of the brain can compensate/take over function of damaged areas of the brain, and memories of different types of experiences are stored in different brain regions.
• Retroactive Interference

  NEWLY learned information reduces recall of previously learned information
• Explicit/Declarative Memory

  • Consciously retrieved. Semantic: Memory of world knowledge. Episodic: Memory of a specific event.
• Parts of the Brain Involved with Memory

  Amygdala: Embeds emotionality in memory traces. Hippocampus: Memory consolidation of explicit memories, Stores spatial memory. Cerebellum: Creating implicit memories. Prefrontal cortex: Retrieval of semantic memories
• Proactive Interference

  PREVIOUSLY learned information reduces recall of newly learned information
• Implicit/Non-declarative Memory


  • Automatic retrieval of knowledge. Procedural skills, Priming, Conditioning, Habituation/Perceptual Learning
• Amnesia is the loss of memory or memory abilities caused by brain damage or disease. Retrograde Amnesia: The loss of memory for events before a brain injury. Anterograde Amnesia: The disruption of memory for events occurring after brain injury; that is, acquiring new long-term memories
• Measuring Explicit Memory

  Recall: generating previously remembered information. Recognition: selecting previously remembered information from an array of options
• 3 Systems of Memory

  • Sensory Memory: Brief storage of perceptual information before it is passed to short-term memory. Each sense has its own form of sensory memory. Iconic (visual) lasts only 1 second. Echoic (auditory) can last 5-10 seconds.
  • Short-term Memory: Only a limited amount of information can be “held” at once (bottleneck). 7 + 2 CHUNKS! (George Miller, 1956) of information (numbers, words, ASL). Chunk = group of information; size of chunk can vary. Loss of information due to Decay: information fades over time. Interference: loss of information due to competition with new, incoming information. Proactive and Retroactive interference. Memory system that retains information for limited durations. Brief in duration; 5-20 seconds.
  • Long-term Memory: Relatively enduring store of information. Two main types: Explicit/Declarative and Implicit/Nondeclarative.
• Memory Reconstructive: '“Human Memory Works like a Tape Recorder or Video Camera, and Accurately Records Events We’ve Experienced”'
• Prefrontal cortex


  • Involved in retrieval of semantic memories
• Surgery on H.M. resulted in severe anterograde amnesia
• Anterograde Amnesia is the disruption of memory for events occurring after brain injury; acquiring new long-term memories is affected
• Performance increased with practice, but no awareness of why that might be
• Types of memories

  • Procedural memory
  • Motor learning
  • Classical conditioning
• H.M.’s procedural (implicit) memory was normal
• Amnesia is the loss of memory or memory abilities caused by brain damage or disease
• Children are highly vulnerable to suggestions to recall events that did not happen
• People are more likely to give a higher speed estimate when the verb implies greater impact
• Stephen Ceci and his colleagues (1994) asked preschool children to imagine real and fictitious events

  1 week later, 58% recalled a story regarding at least one fictitious event
• Most events we experience are never encoded in the first place
• Enhancing Memory: Mnemonics

  Conscious memory aids (strategy) used to r
• This can be magnified by showing people photos of themselves, or by encouraging mental imagery (imagination inflation)
• Memory does NOT work like a tape recorder. We reconstruct memories, not passively reproduce them
• 7 Sins of Memory

  • Sins of Omission
  • Transience – Forgetting over time
  • Absentmindedness – Encoding failure; lapses of attention; forgetting to do things
  • Sins of Commission
  • Misattribution – Source-monitoring error
  • Suggestibility – Information provided by others incorporated into own memory
  • Bias – Held beliefs, knowledge, and feelings distort acquisition of new information (e.g., stereotypical bias)
  • Persistence – Inability to forget information (rumination)
• False Memories: Implanted Memories

  • Research has shown that it is possible to implant a new memory of an event that never happened
• Attention failures were observed in the Penny Experiment by Nickerson and Adams (1976)
• 25% continued to insist that the event was real even after being told by parents and researchers that they were not
• Retrograde Amnesia is the loss of memory for events before a brain injury
• False Memories: Leading Questions and Memory Distortions

  • Loftus and Palmer (1974)
  • Students were asked to describe the accidents and answer questions about what they had seen
• Childhood Memories: Fake Photos
• Objective of task

  To trace object viewed through the reflection of a mirror
• Researchers find no evidence to support claims of repressing and later recovering memories of abuse with memory recovery therapists
• People were lousy at identifying the penny and couldn’t draw it either
• Repeated study gives students a false sense of confidence that they know more than they actually do know
• Two Types of Rehearsals

  1. Maintenance (shallow) rehearsal: Low-level, repetitive information recycling

  2. Elaborative rehearsal: A more complex kind of rehearsal that uses meaning to help store and remember information
• Bias

  Held beliefs, knowledge, and feelings that distort the acquisition of new information (e.g., stereotypical bias)
• Mnemonics


  • Conscious memory aids used to remember information
  • Examples: Please Excuse My Dear Aunt Sally, Every Good Boy Does Fine, Method of Loci (mental palace)
• Roediger & Karpicke (2008) found that retrieval practice/testing was much better for long retention intervals compared to repeated study
• Prose passages

  • Sea Otters, Sun, Bats
  • Vocabulary words: Swahili - wingu (cloud), Russian - medved (bear), Chinese - 大 (big)
  • Birds
  • Face-name
  • Location of objects
  • Population: 3rd/4th graders, elderly (~80 years old)