Memory

• short-term memory

  (Working memory) Immediate memory for occuring events. Measured in seconds and minutes as opposed to hours and days. The memories are displaced or disappear if not rehearsed.
• long-term memory

  Long term memory for past experiences or events. It’s duration is potentially unlimited as well as its capacity.
• capacity of STM

  Joseph Jacobs found the average span for recall of digits was 9 and 7 for letters, thus the capacity of STM is said to be 7± 2 items. Ppts told a digit/letter and repeated it back immediately, more digits/letters added to the letter sequence.
• capacity of LTM

  Potentially unlimited
• duration of STM

  Peterson and Peterson - consonant syllable and three digit number. Recall it after retention intervals of increasing seconds, while counting down from the number. only 2% were correct after 18 seconds, thus STM has a duration of around 18 seconds if rehearsal is prevented.
• duration of LTM

  People of various ages tested on ability to recall the memories of former classmates. After 48 years 70% could recall using photo recognition but only 30% could recall after 48 years in free recall.
• how is long-term memory encoded?

  semantically
• memory: the ability to encode, retain and retrieve information based on past knowledge and experience.
• sensory memory

  The memory of sensory information through the senses.
• capacity of sensory memory

  unlimited capacity
• duration of sensory memory

  very low (milliseconds)
• How is sensory memory encoded?

  modality specific.
• the multi store model of memory (Atkinson) suggests that memory is transferred between three separate memory stores.
• sensory register: the first stage of memory, where information is stored in the senses, collected by eyes, ears and nose etc.
• information moves from the sensory register to the short term memory store via the sensory store, if attention is focused on the sensory store. if not, the info is lost.
• information is held in short term memory. In order for it to go into long term memory, it must be repeated and rehearsed first.
• maintenance rehearsal is when information is repeated to maintain the information in the LTM. the more it is rehearsed the better it is remembered.
• elaborative rehearsal involves linking new information with existing knowledge. this helps transfer the info from STM to LTM
• When memory is in LTM it can now be accessed. This means that information has to be transferred back to short-term memory to be recalled.
• Weakness of MSM

  It is oversimplistic. States that STM and LTM are single ‘unitary’ stores but doesn’t take the type of memory into acccount, as STM is divided into many different stores within itself. Thus MSM is too simplistic of an explanation of memory.
• Strength of MSM

  research support from lab controlled studies on capacity, duration and encoding. Brain scans show prefrontal cortex is active for STM but not LTM. This proves the basis that there are separate stores in the MSM, thus it can be generalised.
• Weakness of MSM

  It emphasises maintenance rehearsal for memories to be transferred to LTM. Studies have proved that memories are created by processing rather than rehearsal (more words remembered in deep processing task than shallow processing task). therefore the model is too simplistic as it doesn’t fully explain the full process of creating long term memories.
• strength of MSM

  Case studies from patients with brain damage. HM’s hippocampus was removed and could no longer form new LTM’s but could remember the old ones prior to the removal. Proves the models explanation of separate stores, STM and LTM.
• Who created the working memory model?

  Baddeley and Hitch
• the central executive: brings attention to the task, allocates resources to the task, and monitors performance.
• the episodic buffer: receives input from the STM and integrates the information to create a mental episode.
• phonological loop: holds information about words and their sounds, involved with maintenance rehearsal. it has a limited capacity.
• visuo-spatial sketchpad: a mental representation of the spatial relationships between objects and the locations of objects in the visual field.
• Strength of the WMM

  Evidence for the phonological loop through its explanation of the word length effect. Word length effect disappears if given an articulatory suppression task (‘repeating the, the, the) as rehearsal is stopped. the phonological loop explains articulatory process; key component of WMM.
• weakness of WMM

  Case studies from brain damaged patients is unreliable evidence. Brain damage can change behaviour or ability to make an individual perform worse on a task, mental issues affect attention span. lots of key research about the WMM comes from these case studies, and the results cannot be generalised.
• types of long-term memory

  Episodic, procedural, semantic
• episodic long-term memory is the memory of personal and unique experiences and events that occurred in the past. involves emotional and contextual details. it is also the most unreliable form of memory.
• semantic long-term memory is the memory of universal knowledge, such as dates of events, facts, and concepts. it is not drawn from personal experience as it lacks contextual cues.
• procedural long-term memory is the memory of automatic actions that are muscle-memory once learned. this includes walking, riding a bike of swimming. it is also known as motor memory as it is acquired by repitition and practice. it is also implicit, meaning it has implied meaning.
• Strengths of types of LTM

  Evidence from brain scans - Proof that there are three separate areas of the brain for each type of LTM.
• where in the brain is episodic memory located?

  hippocampus/frontal lobe/temporal lobe
• where in the brain is semantic memory located?

  temporal lobe
• where in the brain is procedural memory located?

  cerebellum
• weakness of types of long term memory

  Original theory may be too simplistic in explanation. Priming and implicit memories. Priming is controlled by a different system than the temporal, possible fourth LTM.
• what are the explanations for forgetting?

  interference and retrieval failure