Memory

• Retrieval failure when we don’t have necessary cues to access memories
• Multi store model describes the flow between different memory stores in the brain.
• Coding is how memory is stored
• Duration is how long memory lasts before decaying
• Capacity is how much can be stored in memories
• Stimuli from environment passes through the sensory register which registers for each sense
• capacity is very high in sensory register
• duration in sensory register is less than half a second unless attention is paid to it
• Coding In sensory register is modality specific so codes specifically to senses
• Iconic codes Visual information in the register
• Echoic codes auditory info in the sensory register
• if attention is paid to stimuli it will enter STM
• information in the STM is coded acoustically
• Duration in the STM is 18 seconds without rehearsal
• Capacity In the STM is 7 chunks
• maintenance rehearsal is the repetition of information which will remain In the STM
• Long term memory codes semantically
• Capacity is limitless in LTM
• Duration in LTM is permanent (lifetime)
• Through rehersal information is passed from STM to LTM
• Retrieval is where memories is passed from LTM to STM requiring a cue
• Disadvantage of msm researchers conducted a study with pps who had amnesia. Digits read aloud recall was poor. When pps read themselves recall was much higher. Suggesting there could be a nonverbal store in the STM contradicting evidence of the STM being unitary stated my MSM. Questioning the validity of the MSM
• supporting evidence from brain scanning technique. STM is linked with activity is the prefrontal cortex and LTM is linked with activity in the hippocampus. Therefore there is biological evidence that different types of memory are processed by different parts of the brain and memory stores are distant like the MSM states.
• Supporting evidence that seperate memory stores exist. (Murdock) - 2000 participants were asked to recall a list of words. 100 words were presented to each participant. Greater recall for words at the beginning and end. Supports MSM as words reheasred at beginning passed into the LTM. Words at the end were stored in the STM for 30 seconds without rehearsal.
• Criticisms of Murdocks research, he used a large sample size but only tested one group so it may not apply to everyone meaning it lacks population validity . Also his results can't be generalised because they were all students which means their working memory capacity might have been greater than others
• episodic memory It is the collection of past personal experiences that occurred at a particular time and place they are timed stamped and require effort to be recalled.
• semantic memories is knowledge of the world and concepts It is less declarative and time stamped.
• procedural memories are skills we acquire through practice such as riding a bike or playing an instrument. They are automatic and do not need conscious thought to perform them.
• Anxiety is a state of physial and mental arousal
• Johnson and Scott investigated weapon focus with two groups. First group heard arguments in the adjacent room and saw a man walk out with a pen and grease on his hands and the next group saw a man with a knife and blood on his hands. 49% of the pen group recalled the man in the line up whereas 33% in the knife group. Showing how anxiety has a negative effect on recall.
• Yuille and Cutshall (1986) studied a real-life robbery of a gun shop.
• 13 witnesses took part in the study and were interviewed 4-5 months after the event.
• Participants who reported experiencing the highest levels of stress were more accurate in their recall of details of the event than those that reported feeling less stressed, with 88% accuracy compared to 75%.
• This suggests that anxiety can have a positive effect on EWT.
• Supporting evidence from Clive wearing who suffered from amnesia. Whereby his procedural memory was intact and could play instruments and tie his laces. His semantic memory was also  unaffected  However his episodic memory was damaged and he was unable to recall events from his past.  supporting tulving’s  ideas on the different stores in the LTM.
• Evidence from brain scan techniques supporting the idea that different memories are stored in different parts of the brain. Tulving got participants to perform various memory tasks scanning their brains using a pet scanner. Results showed that the left prefrontal cortex was used to recall semantic memories and the right prefrontal cortex was to recall episodic memory. Supporting the idea of the physical reality of different stores in the LTM
• Clive wearing study is based upon a case study. therefore problematic as case studies are on singular people and the same conditions could affect people differently thus they can't be generalised and classed as representative lacks population validity.
• brain scans show different parts of the brain being active when the LTM is active. semantic is associated with temporal lobe, episodic associated with temporal lobe and hippocampus and procedural is associated with basal ganglia and cerebellum. Therefore providing biological evidence on the insight of memory stores increasing external validity.
• pickle conducted an experiment using handgun, wallet and a raw chicken but ewt was worse in the unusual conditions like the chicken. Therefore there is an alternative explanation to Johnson and scots theory that the participants were surprised and not scared. As the tunnel focus on these objects may have been a distraction rather than a threat.
• Support for positive effects - Christianson and Hübinette interviewed witnesses to a crime in Sweden, including bystanders and those directly involved. They found that those who were directly involved in the crime (such as the bank clerk) had higher EWT. Accuracy of recall was 70% on average across all witnesses. This suggests that anxiety does not have a negative effect on EWT and instead may benefit it. Therefore having high ecological validity.