MemoryChapter 6

Memory

Memory is the ability to recall past learning, events, images, and ideas

It is also the storage system that allows a person to retain and retrieve information

Neuroscience and Storage

Hebb suggested that when groups of neurons are stimulated, they form patterns of neural activity

When specific groups of neurons fire frequently, they establish regular neural circuits

Neuroscience and Storage

H. M. was a man whose brain was damaged as a result of a surgery performed to control epilepsy

His short-term storage was intact, but he was unable to form new long-term declarative memories

The process of forming permanent memories is called consolidation

Neuroscience and Storage

If a neuron is stimulated, biochemical processes make it easier for the neuron to respond again

This increased responsiveness is long-term potentiation

It is now accepted that the structure of synapses change after learning

Retrieval

Retrieval is the process by which stored information is recovered from memory

Two measures of retrieval are recall and recognition

Recall

In recall tasks, participants must retrieve previously presented information

The information usually consists of lists of digits or letters

Recall

In free recall, participants can remember items in any order

Serial recall is more difficult because the items must be recalled in the order they were presented

In paired associates tasks, participants are given a cue to help them recall the second of a pair of items

Recognition

In a recognition task, the participant must recognize a previously encountered item

Multiple choice questions are an example of a recognition task

Relearning

Relearning assesses how long it takes to relearn previously learned material

Rapid relearning is assumed to indicate some residual memory

Encoding Specificity

Retrieval is faster and more accurate if given a cue that relates to some aspect of the originally restored item

This supports the encoding specificity principle, that the effectiveness of a retrieval cue depends on how well it matches up with the original encoded memory

State-Dependent Learning

State-dependent learning is that information learned while a person is in a specific state is recalled most accurately if the person is in that state again

State-dependent learning is associated with drug use, time of day, and traumatic experiences

Flashbulb Memory

Vivid memories of dramatic events are referred to as flashbulb memories

Brown and Kulik argued that there is a special type of memory for events that have a critical level of emotionality and what they called consequentiality

Gender and Memory

Research shows very few differences between women’s and men’s memories

Men and women do attend to different types of information

Primacy and Recency Effects

In a serial position study, participants are asked to recall a list of words

Typically, recall is high for words at the beginning of the list, a primacy effect, and for words at the end of the list, a recency effect

Figure 6.8 A Serial Position Curve

Imagery

Imagery is the creation of a mental picture of a sensory or perceptual experience

Paivio suggests that words connected via images become conceptually linked

Forgetting: When Memory Fails

Hermann Ebbinghaus was the first person to study memory scientifically and systematically

His research was performed with three letters strung together to form nonsense syllables

Initially, he found that shorter lists could be learned more rapidly than longer ones

Forgetting

Later, Ebbinghaus used relearning, or what he called the savings method

In this method, he measured how long it took people to relearn a list after varying amounts of time

Ebbinghaus found that forgetting occurs rapidly

Figure 6.12 Ebbinghaus’s Forgetting Curve

Forgetting

Frederick Bartlett found that college students changed stories when they recalled the stories

Students shortened and simplified details (leveling)

Other details were emphasized more (sharpening)

Participants also altered facts to fit their world view (assimilation)

Forgetting

Reconstruction occurs because people develop a schema

A schema is a conceptual framework that organizes information

Key Causes of Forgetting

Decay is the loss of information from memory due to disuse and the passage of time

Interference is the suppression of one bit of information by another

Interference

Proactive interference (inhibition) is a decrease in accurate recall of information as a result of the effects of previous learning

Retroactive interference (inhibition) is a decrease in accurate recall as a result of the subsequent presentation of information

Figure 6.14 Proactive and Retroactive Interference

Interference in Attention

Schacter (2001) says interference causes absentmindedness

When people attend to more than one thing at a time, their attention is divided

Eyewitness Testimony

The legal system has generally accepted eyewitness testimony as some of the best evidence

If memory is a reconstructive process, then it is not a literal reproduction of the past

Neuroscience and Forgetting

Much of the early work on the neuroscience of forgetting began with the study of amnesics

Retrograde amnesia is the inability to remember events and experiences that preceded a damaging event

Anterograde amnesia is the inability to remember events and experiences that occur after an injury or brain damage