Psychology Memory Coding and Capacity

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Questions and Answers

What is coding in terms of memory?

The format in which information is stored in the various memory stores.

What type of stimuli did Baddeley use in his research on memory coding?

Artificial stimuli (correct)

Meaningful stimuli

According to Baddeley's research, how is information coded in short-term memory?

Acoustically (correct)

Semantically

What is the capacity of a memory store?

The amount of information that can be held in a memory store. Signup and view all the answers

Who researched digit span to determine the capacity of short-term memory?

Jacobs Signup and view all the answers

Describe the procedure used by Jacobs in his digit span research.

The researcher gives a sequence of 4 digits and asks the participant to recall them in the correct order. If successful, the researcher increases the number of digits until the participant can no longer recall them correctly. Signup and view all the answers

What were Jacobs' findings on the average digit span for letters and digits?

The mean digit span for digits was 9.3 items, while the mean span for letters was 7.3 items. Signup and view all the answers

What is a limitation of Jacobs' research on digit span?

It was conducted a long time ago and may lack modern research standards. Signup and view all the answers

Who proposed the concept of chunking as a way to enhance short-term memory capacity?

Miller Signup and view all the answers

What is chunking?

The grouping of individual items of information into meaningful units. Signup and view all the answers

Who is credited with proposing the 'magic number' of short-term memory capacity?

Miller Signup and view all the answers

What is the 'magic number' in relation to short-term memory capacity?

Most adults can store between 7±2 items in their short term memory. Signup and view all the answers

What is a limitation of Miller's research on short-term memory capacity?

He may have overestimated the capacity of short-term memory. Signup and view all the answers

What is the generally accepted capacity of long-term memory?

It is believed to be unlimited. Signup and view all the answers

What is the duration of a memory store?

The length of time information can be held in memory. Signup and view all the answers

Who conducted a classic study to investigate the duration of short-term memory?

Peterson and Peterson Signup and view all the answers

Describe the procedure used by Peterson and Peterson in their study on short-term memory duration.

Participants were presented with consonant trigrams (e.g., YCG) and asked to remember them. They were then given a three-digit number and instructed to count backwards from that number to prevent rehearsal. The time interval before recall was varied across trials. Signup and view all the answers

What were Peterson and Peterson's findings on the duration of short-term memory?

They found that the longer the interval, the less accurate the recall; at 3 seconds, 80% of triagrams were recalled, while at 18 seconds only 10% were correctly recalled. Signup and view all the answers

What conclusion did Peterson and Peterson draw from their findings on short-term memory duration?

They concluded that short-term memory has a limited duration, lasting approximately 18 to 30 seconds. Signup and view all the answers

What is a limitation of Peterson and Peterson's study on short-term memory duration?

The stimulus material used in the study was artificial. Signup and view all the answers

Who conducted a study on the duration of long-term memory?

Bahrick et al. Signup and view all the answers

Describe the procedure used by Bahrick et al. in their study on long-term memory duration.

They studied participants from ages 17 to 74 and tested their memory using photo recognition tasks with high school yearbooks and free recall tasks where participants tried to recall names of classmates. Signup and view all the answers

What were Bahrick et al.'s findings on the duration of long-term memory?

Participants tested within 15 years of graduation were 90% accurate in recognition, declining to 70% after 48 years. Free recall was less accurate, 60% after 15 years and 30% after 48 years. Signup and view all the answers

What is a strength of Bahrick et al.'s study on long-term memory duration?

It used real-life meaningful memories. Signup and view all the answers

What is a limitation of Bahrick et al.'s study on long-term memory duration?

Confounding variables, such as rehearsal, were not controlled. Signup and view all the answers

Study Notes

Coding of Memory

Memory is stored in different formats across memory stores (STM and LTM).
Baddeley investigated coding by presenting word lists (acoustically similar/dissimilar, semantically similar/dissimilar) for immediate (STM) and delayed (LTM) recall.
Results showed STM is coded acoustically (worse recall for acoustically similar words) and LTM is coded semantically (worse recall for semantically similar words).
This study's use of artificial stimuli (word lists) limits generalizability to real-world memory situations.

Capacity of Short-Term Memory

Capacity refers to the amount of information memory can hold.
Jacobs measured digit span by presenting increasing sequences of digits and letters to participants until they failed to recall them accurately.
Average digit span was 9.3 items, and letter span 7.3 items, suggesting similar capacity for both.
The study is limited by its age and potential lack of consistent control, but its results have been replicated since then.
Miller proposed 'chunking' as a way of exceeding the initial estimate of 7 ± 2 items; grouping individual items into meaningful units.
Miller's magic number (7 ± 2) proposed a capacity for 5-9 items in STM, though later research suggested a lower capacity, possibly only 4 chunks.

Duration of Short-Term Memory

Duration refers to the length of time information remains in memory.
Peterson and Peterson investigated STM duration by presenting consonant trigrams (meaningless groups of letters/sounds).
Participants were asked to count backwards from a three-digit number to prevent rehearsal.
Findings showed that recall accuracy decreased significantly as the retention interval (time between presentation and recall) increased.
This suggested that STM duration is limited to approximately 18-30 seconds without rehearsal.
The artificial nature of the task (consonant trigrams) limits the external validity of the study.

Duration of Long-Term Memory

Bahrick et al. studied LTM duration in a real-life context using a large sample (392 participants).
High school yearbooks were used for photos recognition, and free recall of class mates was used for participants over 17 to 74 years old.
Recognition accuracy was surprisingly high (90% for participants recall within 15 years), dropping to 70% after 48 years. Free recall accuracy was lower overall.
Findings suggest that LTM duration is potentially unlimited, with significant decline occurring over time.
Real life stimuli increases external validity but also introduced extraneous variables and potential for rehearsal.

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Description

Explore key concepts of memory coding and capacity as outlined in psychology, focusing on Baddeley's research on short-term and long-term memory. Delve into findings regarding acoustic and semantic coding, as well as Jacobs' measurement of memory capacity. This quiz challenges your understanding of essential memory principles.