Memory

Modal Model of the Mind Three memory stores Three memory stores Four Control Processes Four Control Processes Long-term memory Working or Short-term Memory Sensory Input Sensory Memory Attention Encoding Retrieval Maintenance Rehearsal

Sensory Memory Store Divided into two subtypes: Divided into two subtypes: iconic memory - visual information iconic memory - visual information echoic memory - auditory information echoic memory - auditory information Visual or iconic memory was discovered by Sperling in 1960 Visual or iconic memory was discovered by Sperling in 1960 Sensory Input Sensory Memory

Sperling’s Experiment Presented matrix of letters for 1/20 a second Presented matrix of letters for 1/20 a second Report as many letters as possible Report as many letters as possible Subjects recall only half of the letters Subjects recall only half of the letters Was this because subjects didn’t have enough time to view entire matrix? No Was this because subjects didn’t have enough time to view entire matrix? No How did Sperling know this? How did Sperling know this?

Sperling’s Experiment Sperling showed people can see and recall ALL the letters momentarily Sperling showed people can see and recall ALL the letters momentarily Sounded low, medium or high tone immediately after matrix disappeared Sounded low, medium or high tone immediately after matrix disappeared tone signaled 1 row to report tone signaled 1 row to report recall was almost perfect recall was almost perfect High Medium Low z Memory for image fades after 1/3 seconds or so, making report of entire display hard to do

How does Information get from Sensory to STM? Who did research in this area?

Selective Attention Also called “Preattentive Processing” Also called “Preattentive Processing” Cherry 1953 Dichotic Listening

Cocktail Party Effect The ability to focus on a single speaker, even if there are many speakers, is known as the “cocktail party effect” The ability to focus on a single speaker, even if there are many speakers, is known as the “cocktail party effect” The hearing impaired have a diminished ability to focus on one speaker when there are numerous contemporaneous sounds The hearing impaired have a diminished ability to focus on one speaker when there are numerous contemporaneous sounds Recent research aims to separate the audio signals so that only the speaker of interest is amplified by the hearing aid Recent research aims to separate the audio signals so that only the speaker of interest is amplified by the hearing aid

Separation Methods Classical methods Classical methods Exploit spectral diversity Exploit spectral diversity Beamforming Beamforming Assumes speech sources of no interest are in far field Assumes speech sources of no interest are in far field Adaptive Noise Cancellation Adaptive Noise Cancellation Assumes availability of reference signal (which must not contain speech of interest) Assumes availability of reference signal (which must not contain speech of interest) Blind Source Separation, BSS Blind Source Separation, BSS Exploit spatial diversity, e.g., speech sources must be spatially distinct Exploit spatial diversity, e.g., speech sources must be spatially distinct

Short Term Memory Store Function - conscious processing of information Function - conscious processing of information where information is actively worked on where information is actively worked on Capacity - limited (holds 7 +/- 2 items) Capacity - limited (holds 7 +/- 2 items) Duration - brief storage (about seconds) Duration - brief storage (about seconds) Working or Short-term Memory Sensory Input Sensory Memory Attention

Short Term Memory Miller – The Magical Number 7, Plus or Minus Two. Miller – The Magical Number 7, Plus or Minus Two. Chunking Chunking Peterson and Peterson – Short Term Retention of Individual Verbal Items. Peterson and Peterson – Short Term Retention of Individual Verbal Items.

Maintenance Rehearsal Maintenance Rehearsal Working or Short-term Memory Sensory Input Sensory Memory Attention Allows information to remain in working memory longer than the usual 30 seconds Maintenance rehearsal

Working Memory Model Baddeley (1992) Baddeley (1992) 3 interacting components 3 interacting components Central Executive Phonological Loop Visuospatial Sketch Pad

Working Memory Model Visuospatial sketch pad - holds visual and spatial info Visuospatial sketch pad - holds visual and spatial info Phonological loop - holds verbal information Phonological loop - holds verbal information Central executive - coordinates all activities of working memory; brings new information into working memory from sensory and long-term memory Central executive - coordinates all activities of working memory; brings new information into working memory from sensory and long-term memory Central Executive Phonological Loop Visuospatial Sketch pad

How does Information get from STM to LTM? Who did research in this area?

Encoding and Levels of Processing Craik and Tulving 1975 Type of Processing Shallow -Acoustic Deep Shallow - Visual Percent of words recalled

Positive correlation between grades and use of elaboration in 5th grade students Positive correlation between grades and use of elaboration in 5th grade students In an experiment, college students assigned to use elaboration received higher grades than students not taught elaboration In an experiment, college students assigned to use elaboration received higher grades than students not taught elaboration More Evidence for Elaboration More Evidence for Elaboration

Ways to Use Elaboration Ways to Use Elaboration Actively question new information Actively question new information Think about its implications Think about its implications Relate information to things you already know Relate information to things you already know Generate own examples of concepts Generate own examples of concepts Don’t highlight passage as you read Don’t highlight passage as you read Focus on the ideas in the text Focus on the ideas in the text

Long-term Memory Systems Squire 1993

Explicit Memory Also known as declarative or conscious memory Also known as declarative or conscious memory

Implicit Memory Also known as nondeclarative memory Influences your thoughts or behavior, but does not enter consciousness Implicit Memory Also known as nondeclarative memory Influences your thoughts or behavior, but does not enter consciousness

There is biological evidence for these theories as shown in Pet Scans.

Modal Model of the Mind Three memory stores Three memory stores Four Control Processes Four Control Processes Long-term memory Working or Short-term Memory Sensory Input Sensory Memory Attention Encoding Retrieval Maintenance Rehearsal

Elizabeth Loftus and John Palmer: Memory Experiment and Hypothesis Hypothesis: People will remember a car accident differently if given different language cues (words) about the accident Hypothesis: People will remember a car accident differently if given different language cues (words) about the accident

Loftus and Palmer: Methodology Students watched a film of two cars colliding Students watched a film of two cars colliding Collision was moderate with no broken glass Collision was moderate with no broken glass Different students asked different questions: hit, smashed, collided, bumped, contacted Different students asked different questions: hit, smashed, collided, bumped, contacted

Loftus and Palmer: Results People reported the fastest speeds if the researchers had used the word “smashed” in the question People reported the fastest speeds if the researchers had used the word “smashed” in the question From fastest to slowest reported speeds: smashed, collided, bumped, hit, and contacted groups From fastest to slowest reported speeds: smashed, collided, bumped, hit, and contacted groups VERB MEAN ESTIMATE OF SPEED (MPH) Smashed40.8 Collided39.3 Bumped38.1 Hit34.0 Contacted31.8

Loftus and Palmer: Results One week later, subjects were asked if they had seen broken glass One week later, subjects were asked if they had seen broken glass 32% of subjects asked the “smashed” question said yes; 14% of subjects asked the “hit” question said yes 32% of subjects asked the “smashed” question said yes; 14% of subjects asked the “hit” question said yes

Loftus and Palmer: Results and Implications People remember things differently depending on the language used to describe an event (e.g., “smashed” versus “hit”) People remember things differently depending on the language used to describe an event (e.g., “smashed” versus “hit”) Misinformation effect Misinformation effect

Role of Time : Decay Theory Memories fade away or decay gradually if unused Memories fade away or decay gradually if unused Time plays critical role Time plays critical role Ability to retrieve info declines with time after original encoding Ability to retrieve info declines with time after original encoding Problem: Many things change with time. Something else may change and actually cause forgetting: Interference Problem: Many things change with time. Something else may change and actually cause forgetting: Interference