STM N LTM

• Memory is the process by which we retain and recall
• Short-term memory (STM) – your memory for immediate events, which disappear if not rehearsed. It is sometimes called working memory
• –Long-term memory (LTM) – your memory for events that have happened in the past from anywhere between 2 minutes and 100 years ago. It is the permanent memory store.
• •There is also a sensory register which stores a huge amount information from our senses for a very brief amount of time (about half a second).
• Capacity-The length of time information can be held in the memory store

  Duration-The format in which information is stored in the memory stores. It’s the process of converting information from one format to another.

  Coding-The amount of information that can be stored
• Acoustic coding means that information is stored in the form of sounds
• Semantic coding means that information is stored in the form of the meaning of the experience.
• Jackob's- Capacity Of STM

  Jacobs (1887) developed a technique to measure digit span. The researcher gives, for example, four digits and then the participant is asked to recall these in the correct order out loud. If this is correct, the researcher reads out five digits, and so on until the participant cannot recall the order correctly. This determines the individual’s digit span. Jacobs found that the mean span for digits across all participants was 9.3 items. The mean span for letters was 7.3.
• Capacity for stm: Miller’s Magic number 7   + - 2


  •Miller concluded the capacity of STM was  7    2 items, notes, digits, letters and even words.•Words are remembered just as well as letters.This is because of a process called CHUNKING
• Capacity is potentially unlimited for LTM
• Sperling Duration O f Sensory Register


  In a Lab experiment ppts were shown a grid with 3 rows of 4 letters for 50 milliseconds. Then hey had to immediatly recall either the whole grid or a random row.Results- when ppts had 2 recall the whole grid, they only manged to recall either the 4 or 5 letters, when they were aked to recall a row ppts could only recall 3 item
• Duration Of STM Peterson n Peterson

  Ppts were shown nonesense triagrams and asked to recall them either 3 6 9 12 18 seconds after. During the pause they were asked to cound backwards in 3s from a given number. This was the inteference task. Results, After 3 seconds ppts could recall about 80% of triagrams correctly. After 18 seconds, only about 10% were recalled correctly
• Duration LTM Bahrick 


  392 ppl were asked 2 list the names of their ex class mates (free-recall test). They were then shown a photo and asked to recall the names of people shown (photo- recognition test) or given names and asked to match them to a photo (name-recognition test) Results- Within 15 years of leaving school ppts could recognise about 90% of names and faces. They were about 60% free-recall. After 30 years free recall went to 30%. After 48 yrs name-recognition was about 80% accurate and photo was 40% accurate.