Memory

• Memory


  The processing, storage and retrieval of information acquired through learning
• Encoding


  Conversion of information into a usable form so that it can be neurologically represented ('placed') and stored in memory
• Storage


  Retention of the encoded information over time
• Retrieval


  Recovery of stored information for use when needed
• Sensory memory


  The entry point of memory where new incoming sensory information is stored for a very brief period
• Sensory memory


  • Sensory information remains in sensory memory just long enough for us to attend to and select the information to be transferred to short-term memory for processing
  • Believed to have a relatively unlimited capacity
• Types of sensory memories


  • Iconic Memories (Visual Information, Duration: 0.2 – 0.4 seconds)
  • Echoic Memories (Auditory Information, Duration: 3 – 4 seconds)
• Short-term memory (STM)


  A memory system with a limited storage capacity in which information is stored for a relatively short time, unless renewed in some way
• Short-term memory (STM)


  • STM stores information temporarily, but for a longer time than sensory memory (and less than LTM)
  • In STM, the information is no longer an exact replica of the sensory stimulus, but an encoded version
  • When you pay attention to information in your sensory memory (or to information retrieved from LTM), the information enters your STM
• Capacity of short-term memory


  The number of items that can be actively worked or 'worked on' at any time (5 -9 items)
• Chunking


  When you chunk individual pieces of information into small groups, it increases the capacity of short-term memory
• Duration of short-term memory


  Information is only stored in STM for a temporary amount of time, fading between 18 – 20 seconds, but can sometimes be stored for up to 30 seconds
• Declarative memory

  Explicit - requires intentional retrieval or conscious recall, controlled processing of memory (aware of processing), memory of specific facts or events, often demonstrated through words or symbols, 'knowing that'
• Types of declarative memory

  • Episodic (personal/autobiographical)
  • Semantic (knowledge of the world)
• Episodic memory


  • Autobiographical, personal experiences, personalised memories of events, memories associated with a time (when) and place (where), influenced by psychological and physiological state of the person when event occurred (unique to the individual)
• Semantic memory


  • Knowledge of the world, academic knowledge, specialised knowledge, rules/formulas, general knowledge, facts that do not depend on time and place, not as influenced by the state of the person when the information was learnt (knowledge not unique to the individual)
• Procedural memory


  Implicit - does not involve intentional or conscious retrieval, automatic - without awareness of processing, sometimes called skills or habits, demonstrated through actions, behaviour or performance, 'knowing how'
• Classically conditioned memory

  A type of implicit memory, a result of being classically conditioned to remember something and feel a certain way when exposed to the stimulus
• Types of memories

  • Knowing that short term memory has a duration of up to 30 seconds (Semantic)
  • Recalling how much fun I had at my 15th birthday party (Episodic)
  • Knowing how to ride a bike (Procedural)
  • Knowing that when my mum calls me by my full name, I must be in trouble (Semantic)
  • Knowing how to brush my teeth (Procedural)
  • Knowing that 2 X 5 = 10 (Semantic)
• Retrieval


  • The process of locating information stored in memory and bringing it into consciousness when needed
  • Retrieval cues: Activate a concept or node
  • Intentional (being asked a question)
  • Unintentional (smell)
  • Organisation of information aids retrieval and recall
  • Deeper processing and encoding increases likelihood of retrieval
• Explicit memory

  Memory that is expressed as words or symbols and is easily verbalised
• Types of explicit memory

  • Semantic memory
  • Episodic memory
• Semantic memory


  Memory of facts or general knowledge
• Episodic memory


  Memory of specific events or personal experiences
• Episodic memory


  • Remembering what you did on your last holiday
  • Remembering what you normally do when you get home from school
• Types of implicit memory

  • Procedural memory
  • Conditioned emotional response
• Procedural memory

  Knowledge of skills, habits or actions
• Procedural memory


  • Knowing how to type
  • Knowing how to arrange flowers
  • Knowing how to do your hair
• Conditioned emotional response

  A learned emotional reaction in response to a stimulus or an event that you have formed an association with
• Conditioned emotional response


  • Experiencing fear whenever you go to the dentist because you have had some painful dental work previously
• Conditioned emotional response

  • Typically involves negative emotions such as fear or anger, but can also involve strong positive emotions such as happiness or excitement
• Hippocampus

  Encodes, consolidates and retrieves explicit memories
• Hippocampus


  Transfers newly encoded explicit memories to relevant parts of the brain for permanent long-term storage
• Hippocampus transfers memories to be stored in your neocortex
• Hippocampus

  Interacts with the amygdala to link emotions to explicit memories
• When you have an emotionally arousing experience, your hippocampus encodes the explicit memories of the event, whereas the amygdala encodes the emotions related to the event
• When you retrieve the memory, the hippocampus's activity during memory formation will enable recall of where and when the event happened, and who was with you, while your amygdala will also be activated, so you will remember your emotions during the event
• Neocortex


  The top layer of the cerebral cortex that is involved in high-order mental processes such as language, attention and memory
• Neocortex

  Stores explicit memories for a long time
• Memories are widely distributed throughout the cortex and they are usually permanently stored in the areas where the sensory input was first processed