Cognitive Psychology Ch. 5

Atkinson and Shiffrin's *Control Processes*

active processes that can be controlled by the person. Examples that operate on short term memory: - Rehearsal: repeating a stimulus over and over - Strategies used to make a stimulus more memorable - Strategies of attention that help you focus on specific stimuli

Chunking by Miller

describes that small units can be combined into larger meaningful units. -- a Chunk is a collection of elements strongly associated with one another but weakly associated with elements in other chunks

Alvarez and Cavanaugh (2004) Change Detection experiment

- Used colored squares as well as complex objects - Used the change detection procedure Showed the average number of objects that could be remembered for each type of stimulus.

The Central Executive

- the frontal lobe pays a central role in working memory - Attention controller -- Focus, divide, switch attention -ERP- Controls suppression of irrelevant information

Episodic Buffer in Baddeley's new model of working memory

-- Backup store that communicates with LTM and WM components -- Hold information longer and has greater capacity than phonological loop or visuospatial sketch pad -- fig: 5.21

How we Measuring the duration of short-term memory

-- Read three letters, then a number -- Begin counting backwards by threes -- After a set time, recall three letters After three seconds of counting, participants performed at 80% After 18 seconds of counting, participants performed at 10% This reduction in performance is explained by the existence of *decay*: the vanishing of a memory trace due to the passage of time and exposure to competing stimuli *Short-term memory, when rehearsal is prevented, is about 15-20 seconds*

Measuring the capacity and duration of sensory memory (Sperling, 1960)

Array of letters flashed quickly on a screen Participants asked to report as many as possible *Whole report method:* participants asked to report as many as could be seen -- Average of 4.5 out of 12 letters (37.5%) *Partial report method*: participants heard tone that told them which row of letters to report -- Average of 3.3 out of 4 letters (82%) -- Participants could report *any* of the rows *Delayed partial report method*: presentation of tone delayed for a fraction of a second after the letters were extinguished -- Performance decreases rapidly

Echoic memory:

Brief sensory memory of the things that we hear -- Responsible for persistence of *sound* -- type of short term memory.

Iconic memory:

Brief sensory memory of the things that we see -- Responsible for persistence of *vision* -- type of short term memory.

Baddeley and Hitch (1974) Working memory:

has limited capacity system for temporary storage and manipulation of information for complex tasks such as comprehension, learning, and reasoning Working memory differs from STM: -- STM holds information for a brief period of time -- WM is concerned with the processing and manipulation of information that occurs during complex cognition -- WM is set up to process different types of information simultaneously -- WM has trouble when similar types of information are presented at the same time

Vogel et al. (2005) experiment and how Event Related Potential (ERP) were used.

is recorded by small disc electrodes placed on the scalp and picks up signals of neurons that fire together. Was used in the Vogel experiment to record ERP as they made a judgment and indicates that more space is used in working memory with different high and low capacity tests. Results -- High-capacity participants were more efficient at ignoring the distractors

Visual imagery

is the creation of visual images in the mind in the absence of a physical visual stimulus -- Shepard and Metzler (1971): comparing objects -- Mental rotation task -- Tasks that called for greater rotations took longer is a property of the Visuospatial Sketch Pad

Memory

is the processes involved in retaining, retrieving, and using information about stimuli, images, events, ideas, and skills after the original information is no longer present -- is an *active* any time some past experience has an impact on how you think or behave now or in the future

Proactive interference:

occurs when information learned previously interferes with learning new information -- example: Your native language may make it more difficult to learn and remember a new foreign language

Retroactive interference:

occurs when new learning interferes with remembering old learning -- example: After you get a new telephone number and use it for a while, you may have difficulty remembering your old phone number

Patients with damage to their frontal lobes have problems controlling their attention and a typical behavior is..

perseveration: repeatedly performing the same action or thought even if it is not achieving the desired goal.

Modal Model of Memory diagram

Input->sensory memory-> Short term <-rehearsal or output-> Long term memory

Phonological similarity effect

Letters or words that sound similar are confused. -- is part of the phonological loop.

Word-length effect

Memory for lists of words is better for short words than for long words Takes longer to rehearse long words and to produce them during recall -- is part of the phonological loop.

Baddeley's Working Memory Model

Phonological Loop: consists of two components: that holds verbal and auditory information. --- 1.) Phonological store: has a limited capacity and holds information for only a few seconds --- 2.) Articulatory Rehearsal process: which is responsible for rehearsal that keeps items in the phonological store from decaying. Visuospatial Sketch Pad: holds the visual and spatial information. When a picture is formed in our mind or a task like solving a puzzle or finding your way around campus you are using this process. Both processed are attached to the Central Executive: is where the major work of working memory occurs, which pulls information from long term memory and coordinates the activity with the visuospatial sketch pad and the phonological loop. referred to as the traffic cop of working memory because it focuses specific parts of task and divides the attention between the two tasks.

Working Memory and the Brain

Prefrontal cortex responsible for processing incoming visual and auditory information --- Monkeys without a prefrontal cortex have difficulty holding information in working memory

Articulatory suppression

Prevents one from rehearsing items to be remembered -- Reduces memory span -- Eliminates word-length effect -- Reduces phonological similarity effect for reading words

Atkinson and Shiffrin's *Sensory Memory*

Sensory Memory: The retention, for brief periods of time, of the effects of sensory stimulation. -- Information decays very quickly Persistence of vision: retention of the perception of light -- Sparkler's trail of light: this occurs because the perception of light is briefly held in the mind. -- Frames in film: Holds large amount of information for a short period of time -- Collects information -- Holds information for initial processing -- Fills in the blank Includes both new information received from the sensory stores and information recalled from long-term memory

Funahashi et al. (1989)

Single cell recordings from monkey's prefrontal cortex during a delay-response task -- delayed response task findings that neurons that responded only when the square was flashed in a particular location and that these neurons continued responding during the delay. -- Information remains available via these neurons for as long as they continue firing

Modal Model of Memory by Atkinson and Shiffrin (1968)

Three different types of memory: 1.) Sensory Memory - Initial stage that holds all incoming information for seconds or fractions of a second 2.) Short-term Memory - Holds five to seven items for about 15 to 20 seconds. 3.) Long-term Memory - Can hold a large amount of information for years or even decades

Ericsson et al. (1980)

Trained a college student with average memory ability to use chunking -- S.F. had an initial digit span of 7 and after 230 one-hour training sessions, S.F. could remember up to 79 digits; chunking them into meaningful units

based on the results of the Change detection experiment by Steven Luck and Edward Vogal

by using this procedure they measured the capacity of STM. The experiment when small changes occur in pictures we have a difficult time seeing this changes. Capacity of short-term memory -- Digit span: how many digits a person can remember ---Typical result: 5-8 items