Cog Psych Exam 2 short term memory

Miller's Magic Number 7

George Miller suggested our short term memory holds approximately seven chunks.

Rehearsal

repeating information to extend the duration of retention in short-term memory

long-term memory (Atkinson Shiffrin model)

Information stored here is relatively permanent Enormous capacity for decades old memories in addition to recent memories transferred from short term memory

Atkinson and Shiffrin: Control Processes

Intentional strategies used to improve memory, such as rehearsal Focused on the role of short-term memory in memory and learning.

Shift to "Working Memory"

Led by Alan Baddeley and Graham Hitch in the 1970s First asked, "what does short term memory actually accomplish for our cognitive processes" Established that it's major function is to hold several interrelated bits of info in our minds so that we can work with the information and use it appropriately

Semantics

Meaning of words and sentences

Brown Peterson/Peterson Implications

Memory is fragile for material stored only for a few seconds. Led to subsequent studies regarding short-term memory and its capacity/limitations. Led to further support of the cognitive approach.

Information-processing approach

One approach to cognition that argues (A) our mental processes are similar to the operations of a computer and (B) information progresses through our cognitive system in a series of stages, one step at a time

Critique of the Atkinson Shiffrin Model

1) sensory memory is likely the very brief storage process that is a part of perception rather than actual memory 2) clear-cut distinction between short term and long term memory

Phonological Loop - Neuroscience

1) tasks activate parts of the frontal and temporal lobe of the brain's LEFT hemisphere (left hemisphere generally processes information regarding language) 2) TMS administration to the left parietal lobe resulted in the most errors when processing long but simple sentences. 3) TMS administration to EITHER the left parietal or left frontal lobes when processing long and complex sentences resulted in many errors, both must be engaged when rehearsing and storing complex, lengthy sentences

release from proactive interference

A memory phenomenon in which proactive interference is reduced when a person switches to a new stimulus category, leading to increased recall. For instance, after seeing three groups of letters, then seeing geometric shapes as opposed to a fourth group of letters - this enables release from PI and better recall.

Episodic Buffer

A temporary, limited-capacity storehouse that allows the various components of working memory to integrate information and that serves as an interface between working memory and long-term memory. Solves theoretical problems of CE not storing info and integration of information from different modalities in short term memory. Manipulates info so that you can interpret an earlier experience, solve new problems, and plan future activities. Allows you to bind experiences together that weren't previously connected (Ex: when a friend makes a rude comment to you and you connect that to a time you then made a rude comment to a different friend) Binds words into meaningful "chunks" or phrases for more accurate recall Allows us to create more complex representations that can then be stored in long term memory - limited, temporary memory capacity

Atkinson Shiffrin v. Baddeley's Model

AS model represents short term memory as a unified process, Baddeley's model involves multiple components that work together to enable us to actively process and store info on a short term basis.

ADHD

Also represented more difficulty on working memory tasks than those without, especially CE tasks.

Brown/Peterson and Peterson Experimental Process

Asked participants to study three unrelated letters of the alphabet. Then, they would see a three digit number and count backwards by threes. The counting component was significant and prevented rehearsal of the letters. Then participants tried to recall the letters.

Working Memory

Brief immediate memory for the limited amount material that you are CURRENTLY processing Active coordination of your ongoing mental activities Allows you to keep a handful of items active and accessible for use in a wide variety of cognitive tasks, so that they can be integrated with additional incoming info (think reading, how you have to keep the first part of a sentence active to understand it as a whole) Modern notion that short term memory doesn't just store info, it also actively works with that information

Wickens et al. (1976)

Demonstrated that release from PI could also be obtained when researched shifted the semantic category of items Used the five semantic categories to demonstrate this: occupations, meats, flowers, fruits, and vegetables

Atkinson-Shiffrin Model

Essentially memory involves a sequence of separate steps, in which information is transferred from one storage area to another. A model for describing memory in which there are three distinguishable kinds of memory (sensory, short term, long term) through which info passes in a sequential way as it is processed.

Recent Views on Central Executive

Executive attention network is responsible for similar tasks and operates similarly to CE - research required to identify overlap of the two's functions

Sensory Memory

First memory storage area, which records information from each of the senses with reasonable accuracy. The model proposed that information is only stored here for two seconds or less, and then most of it is forgotten. Most fragile part of the memory process Some information lost and some passed on to short-term memory.

Baddeley and Hitch Study Results

Found that participants with 8 number strings instead of 0 required less than a second longer on the reasoning tasks Error rate remained at around 5% regardless of letter string length This contradicted Miller's magic number theory and suggested people can perform several tasks simultaneously (in this case verbal rehearsal and visual/spatial judgements) Most modern theories agree that there are several components of working memory that can operate somewhat independently.

George Miller

Found that short term memory has the capacity of about 7 (+/- 2) items. 1956 article entitled "The Magic Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information."

Neuroscience in Central Executive

Frontal Cortex most active during CE tasks. Both sides of the frontal region play a role.

Neuroscience Research on Visuospatial sketchpad

Generally, visuospatial tasks activate right hemisphere of cortex Working memory tasks with a strong visual component typically activate the occipital region, which is largely involved with visual perception. Mental rehearsal occurs in frontal and parietal lobes. (Remember these are associated with attention!)

Serial Position Curve

In a memory experiment in which participants are asked to recall a list of words, a plot of the percentage of participants remembering each word against the position of that word in the list. Typically U-shaped, displaying both primacy and recency effects (words are better recalled that were positioned at the beginning and end of the list)

Major Depression and Working Memory

In phonological loop test, participants with depression and without looked at a series of similar sounding letters and were asked to remember them in order. Individuals with depression correctly repeated 3.4 letters in a row, versus 5.3 letters for those without depression. Similar (but less significant) results in visuospatial tasks, those with depression performed slightly worse than those without. Central executive tasks represented the largest differences in performance between the groups, with those with depression performing about half as well as those without on these tasks.

research on visuospatial sketchpad

Limited research, not as much as the phon loop. Hard for get people to visualize objects and such as opposed to naming them verbally. Mary Brandimonte conducted a study in which she had participants silently repeat "la la la" in order to occupy their phon loop. This led to them encoding the items with the visuospatial sketch pad and they were less likely to provide names.

The Brown/Peterson and Peterson Technique

One of two major methods used to assess how much info short term memory can hold. A technique designed by John Brown, Lloyd Peterson, and Margaret Peterson. Researchers present several items to a participant, who is instructed to remember these items. Next the participant performs a distracting task and then attempts to recall the original items. Conclusion: Memory held in memory for less than one minute is frequently forgotten.

visuospatial sketchpad

Part of working memory that process both visual and spatial info. Allows you to look at a complex scene and gather visual information about objects and landmarks. Also allows you to navigate from one place to another. Allows you to store a coherent picture of both the visual appearance of objects and their relative position in a scene. Stores information that you encode from a visual description Example of Alan Baddeley trying to drive and also listen to a football game - visualizing the game made him drift out of his lane. Like other components of working memory, the sketch pad's capacity is limited.

Serial Position Effect Experimental Process

Participants presented with lists of words and then asked to recall them once all the words have been presented.

Brown Peterson/Peterson Results

Participants were able to recall most of the letters in the first few trials. However, after several trials, interference affected their ability to recall the letters accurately. After only a 5-second delay, people forgot approximately half of the letters.

Wickens et al. (1976) Experimental Process

Participants would have 4 trials of words to recall. The first three would be from the same category (for example: fruits) and then a separate category for the final trial. Resulted in recall of the most distinct semantic category from the others (occupations) most accurately indicating semantic factors do play a role in short-term memory. Thus, we know that the number of items stored in short-term memory depends on both chunking strategies and word meaning.

Baddeley and Hitch Study of 1974

Provided evidence that working memory is not unitary. 1) presented string of random numbers to participants who rehearsed them in order (strings varied in number from 0-8 items) 2) at the same time, participants performed spatial reasoning task that asked them to assess if statements about letter order were correct (for instance, A follows B)

Phonological Loop - Uses

Reading, self-instruction, learning new words in your own language and learning a new language, producing language, mathematical calculations and problem solving tasks

serial position effect

Refers to the u-shaped relationship between a word's position in a list and it's probability of accurate recall.

Short-Term Memory (Atkinson Shiffrin Model)

Second stage of memory, holds information for approximately 30 seconds unless it is somehow repeated (rehearsal for example) Memories still fragile, but not as fragile as sensory memory Most memory lost, only a fraction passes on to long term memory.

Miller's Work Was Unusual

Unusual for his time which was characterized by prominent behaviorism (emphasized observable external events). Miller's work contrasted these ideals by proposing that people use internal mental processes to convert external stimuli into manageable chunks.

Application of Working Memory

Working memory capacity and ability to complete working memory tasks correlate with academic performance. Scores on working memory tasks positively correlated with overall intelligence and grades in school. Scores on tests of WM (especially the phonological loop) are usually positively correlated with reading ability. Scores on CE tests positively correlated with verbal fluency, reading comprehension, reasoning ability, and note taking skills.

chunk

a memory unit that consists of several components that are strongly associated with one another

Central Executive

integrates information from the phonological loop, the visuospatial sketchpad, the episodic buffer, and long-term memory. Also plays a major role in focusing attention, selecting strategies, transforming information, and coordinating behavior. Suppresses irrelevant information. Helps you decide what to do and what not to do next. "Like an executive supervisor in an operation." Least understood component of working memory. Does not store information *

Acoustic confusions

people are likely to confuse similar-sounding stimuli According to Baddeley: accuracy at recall is lower when the letters have similar sounding names; people make fewer errors when the letters do not sound similar relative to when they do. Letters were presented visually, however participants must've been translating them to a phonological code in their minds

Working memory approach

proposed by Baddeley; our immediate memory is a multipart system that temporarily holds and manipulates information while we perform cognitive tasks Includes the central executive, Visio spatial sketch pad, episodic buffer, and phonological loop

Random Number Generation Task

requires the research participants to supply one digit every second, creating the random sequence described in this demonstration Approximately every 2 minutes, researchers stopped participants and asked them to write down any thoughts Participants who wrote down thoughts about numbers had been able to successfully generate a random sequence of numbers However, when the participants reported daydreaming, their number sequences were far from random Daydreaming occupied a large portion of their central executive and prevented them from successfully completing another task at the same time.

Primacy effect

tendency for better recall of words at the beginning of a list Generally explained by lack of competition of earlier items in remembering and also that these words are generally rehearsed more frequently.

Recency Effect

tendency for better recall of words at the end of a list

proactive interference

the disruptive effect of prior learning on the recall of new information People have trouble learning new material because previously learned material interferes with their new learning

Phonological Loop

the part of working memory that holds and processes verbal and auditory information Can process a limited amount of sounds for a limited amount of time

transcranial magnetic stimulation (TMS)

the use of strong magnets to briefly interrupt normal brain activity as a way to study brain regions Can be used to stimulate specific regions of the cortex

subvocalization

when you silently pronounce the words that you are reading (also categorized under phonological loop)