George Sterling’s Experiment:1960 Flash of screen: 1/20 second Subjects recalled about ½ of letters 3 tones: top, middle, bottom: played immediately after visual Subjects could identify all three What does this help prove? All nine letters available for recall- only for a moment
Iconic / Echoic Memory Iconic: visual “snapshot of great detail”- a photograph like quality lasts only about a second. echoic: If you are not paying attention to someone, you can still recall the last few words said in the past three or four seconds.
Storage and Short-Term Memory Lasts usually between 3 to 12 seconds. Can store 7 (plus or minus two) chunks of information. We recall digits better than letters. Short-term memory exercise.
Storage and Long-Term Memory long-term memory: no known limits Rajan: recited 31,811 digits of pi.(3hrs. 49 min. / or 3.5/second!) How? Rhythmic memory: “melodic or jarring”- taps feet, sways right / left At 5 years old, memorized the license plates of parents’ guests (about 75 cars in ten minutes). He still remembers the plates to this day. Numbers only: average with names, words
Shereshevskii: 1920’s Short term memory: 70 items Forward / Backward / 15 years Journalist / boss furious- never took notes Asylum: went mad: 15 minutes / 5 years: all memories ran together
How does our brain store long-term memories? Memories do NOT reside in single specific spots of our brain. They are not electrical (if the electrical activity were to shut down in your brain, then restart- you would NOT start with a blank slate).
Long-Term Potentiation (LTP) The current theory of how our long-term memory works. Nerve cell’s genes produce synapse strengthening proteins /enabling LTM formation Synapse / neurotransmission Neural connections gradually strengthen through rehearsal over time
Stress and Memory Stress can lead to the release of hormones that have been shown to assist in LTM. Similar to the idea of Flashbulb Memory.
Explicit / Implicit Memory Explicit Memory (Declarative) Semantic memory: “facts about the world” Tenancy to left frontal cortex Episodic Memory: events in our lives Tendency to right frontal cortex Implicit Memory (nondeclarative) Procedural memory- riding a bike / horse
The Hippocampus Damage to the hippocampus disrupts our memory. Left = Verbal memory Right = Visual / Locations hippocampus = librarian Library = our brain Stores LTM- shelves elsewhere in cortex
Amygdala Emotional memory Traumatic events PTSD (war veterans) sounds, smells, conditions etc. *Hippocampus and Amygdale work together to form LTM