EXAM CHAPTER 5

Memory

the processes involved in storing, retrieving, and using information about stimuli, images, events, ideas, and skills after the original information is no longer present

Modal model of memory

memories pass between three different memory systems, or stores, each store memory differently

What are the memory systems?

information flows through sensory to short term to long term

Sensory memory

stores info gathered through senses for .5 - 5 sec

short term memory

holds a few  items (3–7) for a relatively short period of time (15–30 seconds)

allows us to use our long-term memories in the present

-holds and processes what is happening right now

How do we keep memories active in short term memory?

rehearsal

rehearsal

process of repeating stimulus over and over, usually to remember it, keeps stimulus active in short-term memory

retrieval

process of remembering info that has been stored in long-term memory

Long term memory

essentially limitless and information can last for years

Why might sensory memory have multiple systems?

separate system for each sense

Sperling, study and experiment

-studied capacity and duration of extremely short memories

-he would show participants a display for a very brief duration (50 milliseconds) and would ask them to recall all of the letters they saw, they could typically recall 4 or 5 of the 12 letters, participants reported that they were seeing all of the letters, but when they tried to recall them, they faded quickly from memory

-Sperling changed his task to determine whether the capacity was larger than the four to five items. Used the partial report method, rather than asking them to recall all of the letters, he asked them to recall the letters from the indicated row using a high, medium or low tone to indicate the top, middle and bottom row. In the partial report condition, observers reported over 80% of the letters in the row, indicating that sensory memory can hold most of the information that comes into our sensory system (but for how long?)

-By incorporating a delay, we can examine how long sensory memories last. Sperling varied the delay from 0 to 1 second. He found that the longer delay, the worse the memory performance, by 1 second, performance was similar to that of the initial experiment, Sperling concluded that the sensory store holds most (if not all) of the incoming sensory information but only for a limited duration

Iconic memory

brief sensory memory for visual stimuli that lasts for a fraction of a second after stimulus is extinguished, corresponds to sensory memory stage of modal model

echoic memory

brief sensory memory for auditory stimuli that lasts for a few seconds after a stimulus is extinguished

capacity of STM

around 7 items (7 +/- 2)

chunking

combining small units into larger ones, such as when individual words are combined into a meaningful sentence, can be used to increase capacity of memory

digit span

number of digits a person can remember, used to measure capacity of short term memory

Brown and Peterson & Peterson, study and experiment

-separately developed this same method of testing duration of STM

-they gave participants a group of three letters to remember. After presentation of the letters, participants were given a number from which to count backwards by 3 (preventing rehearsal). After a predetermined amount of time, participants were asked to recall the three letters.

-they found the duration of STM to be 15-30 seconds

Baddeley’s working memory model/ what is working memory

-Baddeley’s updated version of short term memory

-like the original version: limited capacity temporary storage system, stores info for a short period of time

-new ideas: underpins complex cognitive thought, involved in reasoning and comprehending language

episodic buffer

-an addition to Baddeley’s original working memory model

-a “backup” store that brings long term memories into the present. It holds info longer and has greater capacity than phonological loop or visuospatial sketch pad

phonological loop

part of working memory that holds and processes verbal and auditory info

visuospatial sketchpad

the part of working memory that holds and processes visual and spatial info

Brooks (1968), study and experiment

-demonstrated that we must have two distinct systems: one for verbal information and another for visual and spatial information

-The experiment consisted of two different tasks and two different types of responses

-1: spatial mental imagery task. Participants visualize a letter. Start at the upper corner of the letter and move around to each corner and indicate whether the corner was an inside corner or an outside corner either by saying it out loud (in or out) or pointing to an answer/ spatially.

-2: sentence task. Participants memorized a sentence and they had to classify each word in the sentence on whether it was a noun or not, either out loud (yes or no) or by pointing/ spatially.

-performance was best when the task and response were in two different modalities, suggested that there is a limited capacity resource that the task and response are competing for. If the task and response are in different modalities, it reduces the competition. These results support that we have two separate systems: one for verbal information and one for visuospatial information.

central executive

the part of working memory that coordinates the activity of the phonological loop and visuospatial sketch pad, “traffic cop” of working memory

decay

process by which info is lost from memory due to passage of time

phonological similarity effect

effect that occurs when letters or words that sound familiar are confused (such as T and P)

word length effect

notion that it is more difficult to remember a list of long words than a list of short words, shows that the phonological loop has a limited capacity

articulatory suppression

interference with operation of the phonological loop that occurs when a person repeats an irrelevant word while carrying out a task that requires the phonological loop

what area of the brain is critical to working memory

prefrontal cortex