Human Memory

Do you recognize a real penny?

Did you have to look? Did you need to check a real penny

to be sure? Nickerson and Adams (1979) conducted an experiment and concluded that most people are not able to pick the correct penny from this drawing (Weiten 1995).

By the way, it’s the one in the second row, second from the left.

Memory

Involves more than taking in information and storing it in some mental compartment.

Memory involves three enduring questions:

1. How does information get into memory?

(encoding) 2. How is information maintained in

memory? (storage) 3. How is information pulled back out of

memory? (retrieval)

Encoding: Getting information into memory-Attention

Attention involves focusing awareness on a narrowed range of stimuli or events

“Selective Attention”. We must choose what to pay attention to or we would be over run with inputs.

Example: Divided attention while driving.

Encoding: Levels of Processing

Craik and Lockhart propose that incoming information can be processed at different levels—for example:

Structural encoding-physical structures, Capital Letters

Phonemic-what the word sounds like, rhyming words

Semantic encoding-the meaning of the word, associations

Levels of processing theory proposes that deeper levels of processing result in longer-lasting memory codes.

Key Hypothesis

Caik and Tulving (1975) said that retention or the remembering of the stimulus words would increase as subjects moved form structural to phonemic to semantic encoding.

But it was determined that these are not the only way to form memory codes and there are other dimensions to the problem that can improve memory

Elaboration

Is linking a stimulus to other information at the time of encoding.We form associations with other things that aid in the encoding process, they are best if they are personal to us specifically.

Visual Imagery

Another way to enrich the encoding of memory is to create visual images to represent the words to be remembered.

Some are easier than others: (Allan Paivio, 1969)

Concrete Objects: Things or nouns are easiest (juggler)

Abstract concepts more difficult (truth)

Dual Processing Theory of Memory

According to Paivio, imagery aids in the encoding of memory because it provides a second memory code and two codes are better than one.

Dual Processing theory: holds that memory is enhances by forming both semantic and visual codes, since either can lead to recall.

Storage: Maintaining Information in Memory

We use the comparison to computers to discuss memory storage.

Richard Atkinson and Richard

Shiffrin: incoming information passes through two temporary storage buffers- the sensory store and short-term store- before it is transferred into a long term store.

The Information Processing Model

Sensory memory

The sensory memory preserves information in its original sensory form for a brief time, usually only a fraction of a second.

It allows the sensation of a visual pattern, sound or touch to linger for a brief moment after the sensory stimulation is over. An example in vision is the afterimage effect.

It gives you additional time to try to recognize stimuli but does not last long…1/4 of a second. (George Sperling, 1996)

Short-Term Memory

Short term memory (STM) is limited-capacity store that can maintain unrehearsed information for up to about 20 seconds.

With rehearsal- the process of repetitively verbalizing or thinking about information, information can be recycled through your short term memory as if on a loop.

Example: rehearsing a phone number

Durability of Storage

Without rehearsal, information is lost in less that 20 seconds (Peterson and Peterson, 1959) and then the idea was that this was just due to DECAY of memory traces. However, it was found that interference from competing information also contributes.

Demo: List of wordsDemo: read TWA Passage

Capacity of Storage

“Magic number of ten experiment”: people can recall only about seven items on tasks with unfamiliar material.

When short-term memory is filled to capacity it often displaces some of the information currently in STM.

chunking (stored as a single unit)

There are four components to the idea of working memory (Baddley,2001):

1. Phonological Rehearsal Loop: You use recitation to temporarily hold you information.

2. Visuospacial Sketchpad: that permits one to hold and manipulate visual images.

3. Executive control: controls the deployment of attention as needed.

4. Episodic Buffer: a temporary, limited capacity store that allows the various components of working memory to integrate information and relays to LTM.

Short-Term Memory as “Working Memory”

Working Memory

Long Term Memory

• Is an unlimited capacity store that can hold information over lengthy periods of time.

• Long-term memories are durable and can possibly endure a lifetime.

LTM

These memories are permanent and that forgetting occurs only when people cannot retrieve the needed information.

An alternate view assumes that some memories stored in LTM do vanish forever.

Example: A leaky barrel with some marbles falling out.

The idea of flashbulb memories, which are unusually vivid and detailed recollections of momentous events, support the idea of permanent memories.

Flashbulb Memories

Flashbulb memories are vivid and detailed recollections of momentous events.

For example, many people remember exactly where they were during the attacks on 9/11 and the World Trade Tower.

Does the evidence on flashbulb memories provide adequate support for the idea that LTM storage is permanent?

NO, research has shown that they are neither as accurate not as special as once believed. They become less detailed and less accurate with time.

How is Knowledge Represented and Organized in Memory?

Mental representation probably take a variety of forms, depending on the nature of the material

Schema: an organized cluster of knowledge about a particular object or event from previous experience.

People are likely to remember things that are consistent with their schemas than things that are not.

People also recall better when things violate their schema-based expectations.

Semantic Network

A semantic network or net is a graphic notation for representing knowledge in patterns of interconnected nodes and arcs.