(Understand our) Memory

I just finished reading “Memory” (3rd edition) by Baddeley, Anderson and Eysenick. A great book (great in content, but also in number of pages: more than 600) suggested by a friend of mine, working with Cognitive Psychology. Professor Baddeley’s studies on memory are famous enough to find a Wikipedia page on his model of working memory in several languages.

The book is amazing not only for providing the first and the latest scientific findings, as well as sperimental models, everything more or less integrated and written in a structured way, but also for showing the amazing processes behind a field in continuous development, where there’s still too much to investigate and understand! I find fascinating how we are developing a better understanding about our self and how we manage (receive, perceive, understand, store, retrieve and process) information, so a kind of meta-understanding.

Following, my attempt to summarize, in an interactive conceptual mind, all the content of this amazing book that I really suggest you to read! After the map, just a few highlights.

As always: this is intended for educational purpose only, please buy the book and support the authors (moreover: the following content is useful only for an overview or a brief recap on the arguments, but it’s almost useless if you want to seriously study and understand).

Memory – Conceptual mind

If you find issues in displaying and navigating (zoom and scroll) or interacting (close or expand nodes) the following map, you can open it in a new window or download it by clicking here or on the image below:

Main concepts (and some thoughts)

• Our brain is designed to forget what is not important to us.
• Basic difference between our memory and a computer memory: our memory is fallible but flexible (we can use knowledge to meaningful reconstruct partial memories).
• (Psycological) theories, especially the ones involved in soft science, are like maps: they summarize knowledge in structured way to help us understanding, but remind that Map is not the territory and we can’t always rely on the reductionism approach.
• Exactly as it happens in other body/mind-related fields, major inisights come from disfunctional behavior in people after some accident/disease. Best approach here is neuropsychological (e.g.: (f)MRI, EEG, MEG, PET, …), cellular and genetic plus well designed tests.
• Our memory is a much more complex systems than just short-term and long-term memory:
  • Short-term memory (STM): measurable for example in digital span (longest sequence of digits we’re able to remember), it’s responsible of simple retention. Theories involving:
    • Attention
    • Individual differences in tasks performance
    • Neurophysiology
  • Working memory (WM): a memory not only for simple retention, but to work with! Used for example during simple math calculation (e.g.: when you multiply some numbers in mind), can also be trained.
    • Subvocalized self-instructions help in more long-term task switching
    • Modal model: input > sensory registers (visual, auditory, haptic) > STM <> LTM
    • Multicomponent model: visuo-spatial sketchpad <> central executive component <> phonological loop
  • Long-term memory (LTM)
• Several factor for success in learning, including:
  • Total time (circa 10.000 hours of study and practice to master a specific topic), even if you can at least start with just 20 hours, as Josh Kaufman says
  • Deliberate practice (yes, lot of time, but not just mere repetition)
  • Distribute practice over multiple session across a long span of time
  • Curiosity
  • Motivation (intrinsic like the pure desire to know and extrinsic like rewards)
  • Attention (be aware that divided attention drastically reduce encoding information)
  • Sleep (as already discussed here)
• Episodic memory (capacity to recollect specific experiences to use for our “mental time travel”) is helped if material is meaningful and organized; deeper processing leads to better memory. From here, the importance of schemas (hierarchies, matrices, linking concepts) and fully understanding before memorizing a new information.
• Retrieval (the effort to active a target trace given one or more clues) has an activation that spreads via associations in proportion to their strength, but we can have issues in retrieval also when a memory is successfully stored, due to no enough clues or not enough attention, or target poorly learned (again, it’s important to properly understand before memorizing) or we are in the wrong frame of mind. Retrieval is not just reactivation of traces, it’s more like reconstruction, combining like inference and problem solving.
• Forgetting process follow a logarithmic curve, but repeated retrieval of memories slow forgetting. Note that availability in memory (whether it remains in memory) is not equal to accessibility (whether one can really retrieve it).
• Adaptive forgetting is maybe intended as a natural process to reduce demands in congitive control processes (to suppress interference from competititve memories).
• People generally have positive bias in autobiographical memory (may explain perception of life satisfaction, since people tend to avoid remembering unpleasant events, throught direct suppression or substitution, retrieving alternate distracting thoughts).
• Extreme emotional distress can cause loss of access to large chuncks of one’s personal past or identity (psychogenic amnesia).
• Repeated retrieval efforts and appropriate cues can recover some memories, but also create suggestions for false memories!
• In autobiographical memory, for people over 40, temporal distribution of recalled events are more dense from late teens to early 30s, but reminiscence bump works more for positive memories, not for negative ones. Be aware of “flashbulb memories”: extraordinary and emotionally significant events lead to superior autobiographical memories (BUT more vividness doesn’t imply more accuracy!).
• Eyewitnesses is influenced by
  • jurors and police, misleading info before/after and by general and imprecise verbal description
  • what they believe more coehrent with their mental crime-relevant schemas
  • reduction in ability to recognize and remember faces or details due to stress and anxiety
  • “tunnel vision”: memory focused on a specific threat (e.g.: they were too close to a weapon, so focusing only on the weapon much more than observing faces and details)
  • holistic process to recognize a face, so high probability to fail in recognizing and remembering details even between 2 photos
  • familiar face (unconscious transference)
  • being of a different race (we can more easily recognize same-race faces)
  • children and old people more prone to fail
• Important factors to enhance and preserve memory, in the early developing stages, are nutrition and maternal care plus emotional support and simulation through play (to prevent also future cognitive, emotional and social issues).
• Aging, STM is generally preserved (WM less so). Brain tend to shrink with age. Found positive effects of physical exercise (more than social activities). Semantic memory continue to accumulate (e.g.: more vocabulary) but speed and reliability decline. Evidence of “use-it or lose-it” effect.
• Memory systems failures tend to be severe and not reversible
  • Alzheimer is progressive with increasing disruption of other aspects of cognition, with memory one of the first and most severe
  • TBI (traumatic brain injury) is nonprogressive, but persists over a lifetime, generally caused when blow or sudden deceleration cause damage to white matter (sheering or twisting)
  • external aid (diaries, reminders,…) can help
• How to better remember:
  • Loci technique, Pegwords and mnemonic major system, story mnemonic (create a story to link items to memorize)
  • Good ingredients for a good mnemonic technique are:
    • meaningful encoding (relating what is to be learned to pre-existing knowledge)
    • retrieval structure (cues)
    • speed-up (extensive practice)
  • Testing (e.g.: flahcards) has much more effect than re-learning (Probably, retrieval effort trace a 2nd road in the brain to the info)
  • Concept maps (in particular, when maps are self-made and more effectiveness in STEM fields)
  • Reading all the text before underlining and active notetaking work much more than just re-copying

Most people claim they don’t have a good memory, but the point is that probably they just forget to pay attention in things they see/hear. Paying attention is something that can be learned, as Japanese train conductors know: