storage how we retain the information we encode. review the three stage process of memory

Storage

How we retain the information we encode

Review the three stage process of Memory

Storage and Sensory Memory

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’sShereshevskii: 1920’s

Short term memory: 70 itemsShort term memory: 70 items Forward / Backward / 15 yearsForward / Backward / 15 years Journalist / boss furious- never took notesJournalist / boss furious- never took notes Asylum: went mad: 15 minutes / 5 years: Asylum: went mad: 15 minutes / 5 years:

all memories ran togetherall 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.

Types of LTM

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

AmygdalaAmygdala

Emotional memoryEmotional memory Traumatic eventsTraumatic events PTSD (war veterans)PTSD (war veterans)

sounds, smells, sounds, smells, conditions etc.conditions etc.

*Hippocampus and *Hippocampus and Amygdale work Amygdale work together to form LTMtogether to form LTM