3.3 Coding , Capcity & duration

Coding

The way information is stored in memory

Strengths of Coding (AO3)

• Baddeley study → supports idea that there is different coding → semantically similar confusion [LTM] & acoustically similar confusion [STM] ( same as MSM)

Limitation of coding (AO3)

• Oversimplification → STM & LTM are not coding exclusive (can code in other ways), not rigid

Capacity

amount of information a memory store can hold at one time

Strengths of capacity (AO3)

Jacobs study

• Aim: To investigate the capacity of STM.

• Method: digit span technique.

• Ppa were read sequences of digits or letters that increased in length and had to repeat them in the correct order.

• Findings: The average span was 9.3 digits and 7.3 letters.

• Conclusion: STM has a limited capacity.

Miller’s study

• proposed that STM can hold approximately 7 ± 2 chunks of information

• chunk = meaningful unit of information

Limitation of capacity (AO3)

• Miller's estimate may be too high:

Cowan (2001: STM capacity may be closer to four chunks under conditions that minimise rehearsal and chunking.

• individual differences: People may have different memory spans depending on factors such as age, familiarity with the material and strategies used. STM capacity is not necessarily identical for everyone.

Duration

the length of time information remains in a memory store

Strengths of duration (AO3)

Peterson & Peterson

• Aim: To investigate how long information remains in STM when rehearsal is prevented.

• Method: Pp’s were shown a consonant trigram, such as XQJ,

• then asked to count backwards in threes from a number. This prevented them from rehearsing the trigram. Recall was tested after different time intervals.

• Findings: Recall fell from approximately 80% after 3 seconds to around 3% after 18 seconds.

• Conclusion: STM has a limited duration when rehearsal is prevented.

Bahrick et al

• Method: Participants were tested on their memory for former classmates using photographs and name recognition or recall tasks.

• Findings: Participants showed remarkably good recognition of classmates even after many years, including decades.

• Conclusion: LTM can retain information for a very long time, potentially for a lifetime.

Limitation of duration (AO3)

• Artificial task:

• meaningless consonant trigrams is unlike most everyday memory tasks, which often involve meaningful information.

• findings may not fully reflect how long everyday information stays in STM.

• Recognition is not the same as recall:

• Recognising a familiar face or name may be easier than recalling information without cues.

• the study does not prove that every type of LTM lasts a lifetime.