Cognition pt.2 chapter 5-9

Memory

retaining, retrieving and using information about stimuli, images, events ideas and skills after the original information is no longer present

Modal Model of memory

proposed by Atkinson And Shiffrin

Proposed a 3-stage model of memory

1. Sensory memory - less than 1 second

2. Short-term memory - holds 5-7 items for about 15-30secs

3. Long-term memory - long durations

information flows from input → short term, with rehearsal looping it back → longterm

Control processes

Included in the memory system

• active processes that can be controlled by the person and may differ from one talk to another

  • e.g. rehearsal

  • e.g. strategies you might use to help make a stimulus more memorable (related dates and numbers), strategies of attention that help you selectively focus on other information you want to remember

Rehearsal

repeating a stimulus over and over, as you might repeat a telephone number, in order to hold it in your mind longer

Sensory Memory

the retention, for brief periods of time, of the effects of sensory stimulation

• e.g. persistence of vision - seeing light after the lights been turned off

Persistence of vision

the lighted trail is a creation of your mind (when you swing a light around) which retains a perception of the sparkler’s light for a fraction of a second

whole report method (Sperling)

• flashed an array of letters on a screen for 50ms - then asked the participant to report as many as possilbe

  • called this b/c particiaptns were asked to report as many letters possible from the hwole matrix, with an average of 4.5/12 letters

But what if participants saw most of the letters immediately after they were presented but their perception faded rapidly as they were reporting the letters so they only had time to report 4-5 letters, they could no longer see the matrix or remember what had been there

Partial report method

was used to determine which of the two possibilities was at play

• he flashed the matrix for 50mc again, but immediately after, he sounded on 1 of three cue tones to indicate which row of letters the participatns were to report

• with the cues, the participants were able to identify 3.3/4 letters

Sperling concluded that the correct description was that immdeiately after the display was presented, participatns saw an average of 82% of letters in the whole display but were not able to report all of these letters

Delayed partial report method

in which the presentation of cue tones was delayed for a fraction of a second after the letters were extinguished

• participants were able to report only slightly more than 1 letter in a row - the same # of letters they reported using the whole report technique

Ionic memory, or visual icon

brief sensory memory for visual stimuli, concluded by Sperling

• corresponds to the sensory memory stage of Atkinson and Shiffrin’s model

echoic memory

the persistence of sound, lasts for a few seconds after presentation of the original stimulus

Proactive interference (PI)

an interference that occurs when information that was learned previously interferes with learning new information

• e.g. a phone number changes from xxx-5100 to xxx-4100, it would be hard to remember the 4, our mind still jumps to the 5

Digit span

information is not lost rapidly from our STM, but there is a limit to how much information can be held there

• digit span = # of digits a person can remember

Chunking

small units (like words) can be combined into larger more meaningful units → phrases, sentences, paragraphs or stories

• chunk: a collection of elements that are strongly associated with one another but are weakly associated with elements of other chunks

Coding

the way information is represented

• physiological approach to coding - determining how a stimulus is presented by the firing of neurons

• mental approach to coding - by asking how a stimulus or an experience is represented in the mind

Auditory, visual and semantic coding

Auditory: sound of a person’s voice

Visual: image of a person

Semantic: meaning of what the person is saying

Release from proactive interference

the sudden improvement in recall that occurs when the category or nature of memorized material changes, such as switching from dates to names, which removes the build up of earlier interference

• recovering of memory performance after proactive interference (PI) has accumulated

  • when the category changes, the older memories no longer compete - recall improves sharply

Working memory

*replaced short-term memory

its a mechanism that consists of a number of specialized components

• one of the main results for the change: the observation that under some conditions participants could do 2 tasks at once

  • e.g. remembering numbers and reading a text and comprehending its meaning

Working memory is a limited-capacity system for temporary storage and manipulation of information for complex tasks such as comprehension, learning and reasoning

Differences between STM and Working memory

1. STM is a single component, whereas working memory consists of a number of parts

2. STM is concerned mainly with holding information for a brief period of time, whereas working is concerned with the manipulation of information that occurs during complex cognition

Phonological loop

one of the 3 ways working memory accomplishes the manipulation of information

• it holds verbal and auditory information, thus when you are trying to remember telephone # or a person’s name

• briefly stores and rehearses sound-based and verbal information through an “inner ear” and “inner voice”

Visuospatial sketch pad

one of the 3 ways working memory accomplishes the manipulation of information

• temporarily stores and manipulates visual and spatial information such as shapes, colours, locations and mental images

Central executive

one of the 3 ways working memory accomplishes the manipulation of information

• where the major work of working memory occurs

• pulls information from LTM and coordinates the activity of the phonological loop & visuospatial sketch pad by focusing on specific parts of a task and switching attention from one part to another

• it also controls the suppression of irrelevant information

e.g. driving in a new city - phonological loop takes in verbal directions from friend, sketch pad is helping visualise a map of the streets, and central is coordinating and combining these two kinds of information

Phonological similarity effect

one of the 3 phenomena that support the idea of a system specialized for language

• it occurs when letters or words that sound similar are confused

Word-length effect

one of the 3 phenomena that support the idea of a system specialized for language

• occurs when memory for lists of words is better for short words than for longer words

  • explains the initially surprising finding that American children have a larger digit span than Welsh children - b/c it takes longer to pronounce Welsh numbers

Articulatory Suppression

one of the 3 phenomena that support the idea of a system specialized for language

• occurs when a person is prevented from rehearsing items to be remembered by repeating an irrelevant sound such as “the”

it has 3 effects

1. reduces memory span - b/c speaking interferes with rehearsal

2. eliminates the word-length effect

3. reduces the phonological similarity effect for reading words

Episodic Buffer

basically a “backup” store that communicates with both LTM and the components of working memory

• it can hold information longer and has greater capacity than the phonological loop or visuospatial sketch pad

  • helps explain the better-than-expected performance on some tasks

Delayed-response task

early work on physiology or working memory which included a monkey

• requires a monkey to hold information in working memory during a delay period

monkey having to decide where food is stored after being separated by a wall - then gets lowered

Serial-position curve

curve: memory is better for words at the beginning of the list than at the end of the list

Primary Effect

better memory for words at the beginning of a serial-position curve

• words are rehearsed during presentation of the list, so they get into LMT

• to increase, present the list more slowly, so there is more time for rehearsal

Recency Effect

Better memory for words at the end of the serial-position curve

• words are still in the STM

• To decrease, test after waiting 30s after end of the list, so information is lost from STM

Declarative memory

conscious recollection of events we have experienced or facts we have learned

Implicit/non-declarative memory

memory that occurs when a past experience influences behaviour but we are not aware of the experience that is influencing the behaviour