15. Forgetting

15. Forgetting

1. Forgetting

   • Incidental forgetting > Memory failure without the intention to forget
   • Motivated forgetting > Engaging in processes and behaviours to diminish memories
   • Ebbinghaus (1913) tested memory forgetting on himself by learning lists of words. Suggested forgetting increases as time increases = forgetting curve. We forget a lot at first, then forgetting slows
   • Personal memories
     • difficult to know if recollection of personal memories is correct
     • Meeter, Murre & Janssen (2005) asked participants to recall TV/New stories. Memory over time dropped from 60% to 30%, then decreased less steeply
     • Bahrick, Bahrick & Wittlinger (1975) asked high-school students to remember faces and names of those in their year. Ability to recognise face/name among unfamiliar and match names with faces remained high for 30 years Ability to recall name given picture showed more forgetting
   • Nature of forgetting
     • more is recognised than can be stored/recalled
     • Consolidation is needed = systematic and synaptic consolidation
     • Tulving: Suggested forgetting is determined by availability (whether an item is in the memory or not) and accessibility (whether the stored item can be retrieved)

2. When we Forget

   • Trace Decay
     • Trace = a physical change in the brain
     • Memories activation may fade but underlying memory stays intact, or, the memories structural elements degrade
     • Frankland, kohler & Josselyn (2013) suggested memory loss occurs at the same time an neurogenesis = may explain infantile amnesia
   • Contextual Fluctuation
     • As time progresses, changes in the context become greater from context we learnt in
     • Delaney et al (2010) = participants study 2 lists of words, then daydream about a holiday in the US, a holiday away or controls stayed in a dark room. Those daydreaming about a holiday away recalled less
   • Retrieval-Induced Forgetting
     • retrieval can harm the recall of other memories related to the retrieved item
     • Closely related words and memories 'compete' with the memory you are trying to remember causing a temporary forgetfulness
     • McCrae & MacLeod (1999) students learnt 10 geography facts, practiced 5/10 facts = practice facilitated recall of practiced facts but harmed unpracticed
     • Shaw, Bjork & Handal (1995) - questioning harms eyewitness memories for non-questioned details
     • Retrieval Practice Paradigm (Anderson et al, 1994) = People study verbal categories for later memory test, then repeatedly recall some of examples they studied. Following retrieval practice, test given where people are asked to recall all examples they remember seeing from every category. People clearly recall examples they practiced well But retrieval practice leads people to forget related items
     • Cuc, Koppel & Hirst (2007) showed RIF is socially shared
     • Cinel et al (2018) technology may effect RIF
   • Part-Set Cue impairment
     • Tendency for target recall to be impaired by providing retrieval cues drawn from the same set
     • Slamecka (1968) participants studied words from many semantic categories, some received cues other didnt = recieving cues decreased performance
     • Stronger items provide greater competition during retrieval of non-cue items, impairing recall = increased competition
     • Bauml & Aslan (2004) Considered whether presenting cues makes people forget or whether forgetting may be caused by how people use the cues = particiapnts studied categories with 12 examples, part-set group presented 4 items and told they should be used a cues, part-set re-study group saw same 4 items and aske to study them befroe test, part set retrieval group given a test on 4 items before key test. Part set and retireval showed higher forgetting
   • Interference
     • over time, people store so many similar experiences, they interfere with retreiving traces
     • Interference arises when the cue is used to access a target becomes accociated with other memories
     • Competition assumption (Anderson et al, 1994) cue activates all associated and they fight with each other
     • Cue-overload principle = recall decreases as the number of to be remembered items are paried with more experiences
     • Retroactive interference
       • more recently acquired information impedes retrieval of similar memories
       • Barnes & Underwood (1959) people given increasing amounts of training on 2nd word list, memory for those better, but memory for 1st list worse
       • Baddeley & Hitch (1977) rubgy players asked to recall names of teams they played = Forgetting increased with the number of intervening games
     • Proactive interference
       • older memories interfere with retrieval of more recent experiences
       • Underwood (1957) particiapnts learnt list of nonsense syllables = student with no previous expereince remembered 80%, student with learning trials remembered less than 20%

3. Why we Forget

   • Associative Blocking
     • Cue fails to elicit a target trace because it repeatedly elicits a stronger competitor, leading people to abandon efforts to retrieve the target
     • Smith & Tindell (1997) people encoded large set of words and making rating on them, after givenpuszzle solving task (related) = particiapnts solved pusszles related poorly
   • Inhibition
     • Reduction in the activity level of a contextually inappropriate response
     • · Allows an unwanted response to be stopped and an alternative response to be executed
     • Reduced activity of inappropriate response results in long-term diffictuly in procuing the inhibited repsonse
     • Anderson & green (2001) think/no/think paradigm, p's study paris of weakly related words and trained to provide 2nd response word when given 1st. SUbjects stopped to avoid thinking of words = more subejcts treid to stop recall the worse recall become
     • Kuhl et al (2007) p's retrieved same to be practiced items on many occansions, more activation in ventrolateral prefrontal cortex and anterior cingulate cortex on early trials. = brainr egions involved in cognitive control