Lecture 9 Memory pt 1 Memory is involved in many facets of life · Routines and habits . The sense of self o Facts about yourself · Figuring out how to solve problems · Social functions Memory processing stages · Encoding o Learning, studying, putting info into memory. Creating patterns to represent events · Storage o Retaining encoded memory traces (patterns) Retrieval o When a cue activates part of a memory trace pattern, the full trace is recovered Memory in the brain . Encoding: hippocampus forms a memory trace as a pattern of cortical activity · Storage: memory consolidation is when a memory trace transforms into stable, long- term patterns and becomes independent of the hippocampus (this takes time) . Retrieval: when part of that memory trace is activated by a cue, the rest of the pattern is completed Memory systems · Sensory input · Sensory memory o Information not transferred is lost · Short-term memory o Information not transferred is lost o Rehearsal · Long-term memory Sensory memory . Echoic-memory is a sound byte held for about 3 seconds . Haptic memory is a brief memory of a touch · Iconic memory is visual memory held very briefly, also called 'persistence of vision' Iconic memories -- afterimages: · Positive afterimage o Visual memory that is the original image · Negative afterimage o Visual memory that contains the inverted colors from the original image How long does sensory memory last: · George sperling o Showed participants a visual display of 3 x 4 letters for 0.05 seconds and asked participants to recall as many as possible 2 conditions · Whole report: report letters from the whole display " Heard one beep " Participants could only recall 3 or 4 letters . Partial report: report letters only one row at a time · Heard 3 beeps
" Played the tones at different delays from when the image was shown " If the delay was very soon after the image, participants showed a higher chance of recalling all the letters The later the delay, the closer the participants scored to the whole report example " Sensory memory is large, but only lasts for a second Short-term memory · Attended info moves from sensory to short-term memory, an intermediate between sensory and long term memory · Prefrontal cortex . Limited time capacity of about 20-30 seconds, then decay or processed to mvoe to long- term memory · 7 plus or minus 2 Serial positions effect · Primacy effects Better recall first few items from a learned list o Rehearsal and long-term memory . Recency effects o Only short term memory o Recalling later items off a learned list Enhancing short term memory · Chunking o Grouping things together o Increases with knowledge of information o Chess example · Expert chess players were better at remembering chess pieces and their locations than new players . The expert effect is not present when the board configuration does not represent a real game Working memory --