Memory

Encoding

Occurs when information is first translated into a form that other cognitive processes can use. It is held in storage in one form or another for later retrieval.

Modal Model of Memory

The model proposed by Atkinson and Shiffrin that describes memory as a mechanism that involves processing information through a series of stages. Information is briefly stored in sensory memory, attended information is help in short term memory for 20-30s. Then there is a long term memory store for information that needs to be stored for a longer time.

Sensory memory

There is a sensory memory store for each sensory modality. Visual sensory memory, auditory sensory memory, gustatory (taste) sensory memory, tactile (touch) sensory memory. Most research is on Visual and Auditory, which are also called icon and echo.
- information depends more on physical aspect of the stimulus instead of meaningful aspects.

Icon

"after image" or brief memory when you look at something and then it disappears and the image is in your mind for a few seconds.
- information available to the icon is only visual, not auditory.

Masking

information can be erased with other stimuli presented soon after the icon.

Echo

brief memory when you hear something and then it disappears a short while later. Echos can last longer than icons (as long as 20s)

suffix effect

If a list of words is presented in auditory format (instead of visually) and if there is an auditory recall cue (suffix) like a spoken word, recall of the last few items is seriously hindered. The more auditory similarity the suffix is to the items on the list, the greater the suffix effect.

Which sensory memory store is largest?

Visual is larger than auditory, but the length of time auditory is stored is longer.

Primacy effect

improved recall of words at the beginning of the list.

serial position effect

people tend to recall more words at the beginning or end of a list then they do in the middle.

recency effect

improved recall at the end of the list. Results from using sensory or stm. If the participants are given a task to do before reporting words, recency effect disappears.

Short term memory

Sensory information that a person pays attention to is thought to be stored in stm for 1-2mins.
Capacity: 7+/- 2 items
Coding (the way info is mentally represented): people tend to make auditory mental representations instead of visual.
Retention, Duration and Forgetting: If not rehearsed, information can be lost in as little as 20s (memory trace) and then the information is said to decay. There is another theory called inference where information is there but very difficult to recall.
Retrieval: serial, exhaustive search is typically used.

Chunking

a strategy that helps people recall information by separating a long list of numbers or letters into smaller "chunks" - typically 3 in our culture. It helps to remember more information with the limited storage in the stm

Long-term Memory

A place for storing large amounts of information for indefinite amounts of time.
Capacity: virtually unlimited.
Coding: Errors recalling information are due to semantic confusion (note: acoustic similarity affects STM and semantic similarity affects LTM)
Retention Duration: final decline about 30-35 years, indefinitely
Forgetting: the forgetting curve suggests that the more you forget, the more effort required to remember. Forgetting is rapid at first then levels off. Interference instead of decay accounts for forgetting (same as STM). Forgetting is less of a limitation of memory rather a shortcoming of our ability to direct memory.
Retrieval of information: categorization, encoding specificity, context effects, state-dependent learning.

proactive interference

material that is learned first can disrupt retention of subsequently learned material. This can be eliminated by switching stimuli.

Parallel search

Comparing one item in a list to all the others simultaneously. No extra time is required to check all items instead of 1.

Serial search

One item is compared individually to each other element. The longer the list, the more time it takes.

Self-terminating search

A search stops as soon as a match is found.

Exhaustive search

even if a match is found, you continue looking.

Retroactive interference

the disruptive effect of new learning on the recall of old information.

How does interference work?

A retrieval cue leads to the recovery of a target memory. If the retrieval cue becomes associated with other targets, during retrieval the second target competes with the first.

Fan effect

The more concepts you learn about a topic, the more time you need to retrieve information about it.

categorization

memory is improved when material organized into categories is more easily recalled than information with no organization.

encoding specificity

memory is improved when information available at encoding is also available at retrieval. ex: taking a test in the same room you were taught in.

Context effects

environmental stimuli present at the time of encoding can be a good retrieval cue. Doesn't work the same for recognition memory.

State dependent learning

Material learned while someone is chemically intoxicated is usually recalled better when the person recreates that state. Only effective with recall and not recognition memory.

Working memory

A limited-capacity workspace that can be divided between storage and control processing. There are three components: central executive, phonological loop, visuospatial sketchpad and episodic buffer.

Central Executive

directs the flow of information, choosing which information will be operated on, when and how. Limited amount of resources and capacity to carry out tasks. Acts as an attentional system than a memory store.

Phonological loop

carry out subvocal rehearsal to maintain verbal material. Consists of 2 structures: short term phonological buffer (holds onto verbal information for short periods of time, such as a few minutes , assuming rehearsal is not prevented) and a sub-vocal rehearsal loop to compensate for rapid decay of info in the phonological buffer.

visuospatial sketchpad

maintain visual material through visualization. Involves the creation and use of mental images.

episodic buffer

required when remembering specific events from the past or to link information across domains (visual, spatial, verbal) and to sequence various events in chronological order.

Episodic memory

holds memories of specific events in which you participated in. Organization is temporal, one event will be recorded before, after or at the same time as another.

Semantic memory

Holds information that has entered your generic knowledge base. Organization is based on meaning between different pieces of information.