Memory!

Memory!

1. Short Term Memory

   • CAPACITY: Joseph Jacobs used Digital Span Techniques- average for Digits was 9.3 Items and 7.3 for Letters
     • The Magic Number: Miller claimed capacity was 7 (+/- 2) items
     • EVALUATION: Cowan: 4 chunks probably the limit. Simon: Size of chunk matters- fewer recalled. Jacobs: Individual differences found. 19 year olds have longer digit span that 8 year olds
   • DURATION: Peterson & Peterson Studied 24 Students- asked to count back in 3's and asked to recall number at different Intervals (3,6,9,12,15 or 18 Seconds). P's= 90% correct after 3 Secs, 20% after 9 Secs & 2% after 18 Secs.
     • EVALUATION: Naime et al: Duration of STM= 96 Sec. Reitman: Auditory tones to avoid displacement- longer duration of STM.
   • CODING: Baddeley- Difficulty remembering acoustically similar words. STM tries to acoustically.
     • EVALUATION: Brandimote- STM can be visually coded if rehearsal is prevented. Wickens: sometimes uses semantics to code.

2. Long Term Memory

   • CAPACITY: supposedly unlimited
   • DURATION: Bahrick et al- after 48 years, participants were 70% accurate in face recognition and 30% for names of Class Mates
   • CODING: Difficulty remembering SEMANTICALLY similar words. Tries to encode using meaning.
     • EVALUATION: Baddeley- tested after 20mins so is it testing LTM? Frost- Visual Coding. Nelson & Rothbart- acoustic coding in LTM
     • LTM may not always code semantically?

3. Multi- store Model of Memory

   • SENSORY REGISTER: large capacity, very short duration
     • ATTENTION will transfer info to the STM
       • MAINTENANCE REHEARSAL: eventually creates a LTM
   • STM: limited capacity so info DECAYS, limited duration unless rehearsed
   • LTM: unlimited capacity. Forgetting may be due to lack of accessibility to all memories made
   • RETRIEVAL from LTM goes through STM
   • STM/LTM difference SUPPORT
     • Lab Studies- e.g. Jacobs, Miller, Peterson and Baddeley
     • Brain Scans- Beardsley linked STM to Prefrontal Cortex. Squire et al linked LTM to Hippaocampus
     • Case Studies of HM- linked formation of new LTM's to Hippocampus as patient was unable to form new LTM's after having it removed
   • STM/LTM LIMITATIONS
     • MSM is too simple? Can Memory really be linked to only two stores?
     • LTM requires more than Maintenance Rehearsal?

4. The Working Memory Model

   • CENTRAL EXECUTIVE: gives attention to something and allocates tasks to 'Slave Systems'. Has NO storage
     • PHOLOGICAL LOOP: stores order of auditory information
       • INNER EAR: holds words for PL
       • INNER VOICE: performs Maintenance Rehearsal
     • VISUO- SPATIAL SKETCHPAD: planning and processing visual and/or spatial tasks
       • VISUO CACHE: stores form and colour
       • INNER SCRIBE: stores spatial relation e.g. layout of a room
   • EPISODIC BUFFER: records events as they happen. Links to LTM
   • WMM SUPORT
     • Hitch and Baddeley: participants are slower/ less effective when doing dual tasks e.g. using CE and Articulatory Loop- shows they are seperate
     • KF= Patient who occurred damage to Inner Voice. Shallice abd Warrington: problems with verbal material (words not sounds)
     • Damage to Phonological Loop= unable to learn words in pairs presented out loud (Trojano and Grossi)
     • Damage to Spatial System in Car Accident. Performed better on Spatial tasks than those involving visual imagery. Suggests separate Visual and Spatial Systems
   • WMM LIMITATIONS
     • Brain Damage evidence is not reliable as trauma may have an influence
     • Central Executive cannot explain everything. Eslinger and Danasio have evidence to suggest it is more complicated

5. Types of LTM

   • Episodic Memories: personal memories of an event/ episode forming a sequence. Includes context and emotional detail
     • Associated with the Temporal Lobe (Hippocampus) and Frontal Lobe
   • Semantic Memories: Knowledge of the world that is shared by everyone. For example remembering that the age you go to Nursery is a SM but what its like to go to Nursery is a EM
     • Associated with the Temporal Lobe
   • Procedural Memories: relates to skills such as Riding a Bike or how to behave towards people. Knowing how you should behave is a SM. Comes about by practice and are usually IMPLICIT Memories.
     • Associated with the Cerebellum, Basal Ganglia and Limbic System
   • HM- New Procedural Memories could be formed but not Semantic or Episodic. Shows they are separate stores
   • Evidence from Amnesia Patients: can form Semantic Memories independently of Episodic Memories
     • How reliable is Brain Scan Evidence? Can it correctly identify certain areas of the Brain?