Research into coding and capacity

• Outline the procedures of research into the coding of the sensory register.


  A researcher presented participants with different types of sensory information e.g. visual and auditory Information.

  The researcher then measured the length of time in which participants could remember these different types of Information.
• Outline the findings of research into the coding of the sensory register.


  Participants could remember the visual information for a few milliseconds but could remember auditory information for slightly longer.

  If they last for different durations, they must be coded/stored differently. As a result, the coding of the sensory register is modality specific i.e. depends on the type of information being stored.
• Outline the procedures of research into the capacity/duration of the sensory register.


  In task 1, participants were briefly presented with a grid containing 12 letters before being asked to recall them.

  In task 2, participants were briefly presented with another grid containing 12 letters before being asked to recall the 4 letters from a specific row.
• Outline the findings of research into the capacity/duration of the sensory register.


  In task 1, participants recalled, on average, 4-5 of the 12 letters. In task 2, participants recalled 3 out of the 4 letters from the specific row asked.

  This suggests that the capacity of the sensory register is large - participants in task 2 stored most of the 12 letters to be able to recall most of the letters from a specific row. However, the duration of the sensory register is brief/approx. 250 milliseconds.
• Outline the procedures of research into the coding of the STM and LTM.


  A researcher presented participants with random lists of words that were acoustically similar, acoustically dissimilar, semantically similar or semantically dissimilar. 

  Participants were asked to recall the words in each list either after 20 seconds (to test their STM) or after 20 minutes (to test their LTM)
• Outline the findings of research into the coding of the STM and LTM.


  When testing their STM (i.e. recalling after 20 seconds), participants confused the list of words that were acoustically similar, suggesting STM is coded acoustically.

  When testing their LTM (i.e. recalling after 20 minutes), participants confused the list of words that were semantically similar, suggesting LTM is coded semantically.
• Outline the procedures of research into the capacity of the STM.


  A researcher provided participants with a series of digits and asked them to immediately recall the digits in the correct order.

  As the test continued, the list of digits became longer (i.e. another digit was added).
• Outline the findings of research into the capacity of the STM. 


  Participants could remember lists of up to 9 digits. The average was 7 digits, and the lower boundary was 5 digits.

  This suggests that STM has a limited capacity of 7+/-2 (between 5-9).
• Outline the procedures of research into the duration of the STM.


  Researchers provided participants with consonant trigrams one at a time before asking participants to count backwards in threes from a specific number (to prevent them rehearsing the consonant trigram). 

  After varying time intervals, participants were asked to stop counting and recall the trigram.
• Outline the findings of research into the duration of the STM. 


  After 3 seconds, participants could recall most of the trigrams correctly but after 18 seconds, only a minority were recalled correctly.

  This suggests that STM has a short duration, approximately 18-30 seconds.
• Outline the procedures of research into the capacity of the LTM.


  A researcher wrote a diary of thousands of events they had experienced over several years.

  They then tested their recall of these events by attempting to describe when, where and what happened.
• Outline the findings of research into the capacity of the LTM.


  The researcher found they had excellent recall of the thousands of events in their diary.

  This suggests that the capacity of LTM is very large.
• Outline the procedures of research into the duration of the LTM.


  Researchers obtained a sample of graduates who had either graduated recently or a long time ago.

  They were shown photographs from their high school yearbook and were asked to either match names provided to the people in the photo or freely recall their names.
• Outline the findings of research into the duration of the LTM.


  Participants who graduated more recently were better in both tasks however those who had graduated many years ago were still able to match most the names to the faces and were able to freely recall some of the names.

  This suggests that LTMs can potentially last a lifetime, though they may naturally decay over time or need cues for retrieval.
• Evaluate research into the the sensory register/STM/LTM: highly controlled.

  This Is because the participants' memories were tested in controlled laboratory environments whereby standardised procedures could be employed. For example, they could control how many words were presented, how long for, the time delay between presentation and recall etc. This is a strength because it allows for the research to be easily replicated to check the reliability of the findings into the coding/capacity/duration of memories.
• Evaluate research into the sensory register/STM/LTM: unnatural environment.

  This is because most of the research was carried out in a controlled laboratory environment which lacks the distractions that may affect our memories in our everyday environments. This is a limitation because the findings into the coding/capacity/duration of memory may not accurately represent the coding/capacity/duration of our memories in everyday life. E.g. the capacity and/or durations of our memories may be less/shorter in real life due to the constant amount of distractions in our environment.
• Evaluate research into the coding/capacity/ duration of the sensory register/STM/LTM: artificial tasks.

  This is because most of the research has involved presenting participants with random lists of words/numbers. This is a limitation because this does not represent how we use our memories in everyday life and so the research into the coding/capacity/duration of our memories may lack mundane realism. E.g. the capacity and/or duration of our memories may be larger/longer in real life when information is more relevant and has emotional meaning to us.