Capacity, duration and encoding Flashcards
What is the capacity of the SR?
Very large, unprocessed, highly detailed and ever-changing format
What is the duration of the SR?
Information lost quickly, iconic memory has a frequency of 1/2 a second, echoic has 3 seconds
What is the encoding of the SR?
Very little coding, iconic register - memory for visual information, echoic register - memory for auditory information, haptic register - memory for touch
What was Sperlings study on this?
Presented participants with a number of grids each containing 3 rows of four letters
When asked to recall the grid they remembered 4 or 5 items
When asked to recall only part of the information the participants remembered 9 or 10 items
What are the two main conclusions of sperlings study?
Capacity - the fact participants did not know which they would be asked to recall but had far better recall suggested capacity of the sensory register is larger than 4/5 items
Duration - The time it takes to recall the letters in one row is much faster than reporting the whole grid, therefore, although the capacity of the sr may be large, the duration is very limited at approximately 0.5 seconds
What was Jacobs study on this?
Participants were presented with a sequence of digits or letters and were required to repeat them back in the same order.
Pace was controlled using a metronome and half second intervals
Jacobs found that participants recalled more digits than letters
What were the conclusions of Jacobs study?
The average digit span was 9.3 and letters were 7.3
The capacity increased steadily with age
They were able to recall 7+ or -2 items.
What did Peterson and Peterson study on this?
Investigated how long simple information stays in short-term memory without repetition.
A trigram was used each day and they were asked to recall each trigram after a delay
The longer the delay the more forgetting occurred in the STM
What did Peterson and Peterson conclude?
After 3 seconds 90% were recalled but after 18 seconds 5% were recalled
Without repetition STM lasts for a little longer than 18 seconds
What did Baddeley 1966 study on STM?
Independent groups design, gave them acoustically similar words, dissimilar, semantically similar, dissimilar.
STM condition: Had to immediately remember the words and the recall of acoustically similar lists was poor whereas acoustically dissimilar list was recalled best at 60-80%.
The fact the acoustically dissimilar words were recalled more accurately suggest the STM is not getting muddled on the sound of words
What is the capacity of the LTM
The capacity of the LTM is generally accepted to be unlimited, the store never becomes full
What did Konkle find out about the LTM?
Presented participants with 2912 pictures of scenes at 3 seconds per scenes followed by a test of recognition memory.
Long term memory for these scenes was very good. When participants chose between a previously presented science and a new scene from a category not used during the initial presentation, they were correct up to 96%.
What is the duration of the LTM?
Dependent of the person’s life span memories can last up to a life-time, Information that is processed at a deep level is likely to be remembered for longer, skills are remembered better.
What is coding in LTM?
It is widely acknowledged that coding in the LTM is semantically. There is however some evidence for visual and acoustic encoding in LTM
What did Behrick et al find out about the LTM?
Sample of 392 american ex-high school students aged from 17-74 asked to remember the names of their classmates
90% accuracy in face and name recognition even from those participants who have left high-school 34 years ago.
Concluded that peoples’ long-term memories can last for their whole lives, even though they may weaken over time, recognition is better than recall.
