Companion website: MEMORY
Companion website: Learning objectives be able to define memory understand the nature of the sensory information store, short term memory and long-term memory understand the differences between declarative and non-declarative long-term memory know the brain regions involved in memory know the main developmental factors involved in memory
Companion website: Memory Capacity that permits us to benefit from past experience (Tulving, 1985) Divided into sensory information store (SIS), short-term memory (STM) and long-term memory (LTM) Motor memory is the ability to consistently reproduce a skill over a period of time Divided into short-term motor memory (STMM) and long-term memory (LTMM)
Companion website: sensory information store Holds all incoming information If not attended to it is lost 0.5 s Rehearsed information is passed to STM
Companion website: short-term memory 90% of information is lost 10 s Only rehearsed information is retained Has a limited capacity of 7±2 bits of information in adults (Miller, 1953) We overcome limitations to some extent by chunking – grouping things together e.g. we remember telephone numbers by chunking them into sets of 3 or 4 numbers Each set or chunk becomes one bit of information labelling – we give groups of things names or labels
Companion website: Forgetting in short-term memory Forgetting occurs due to: failing to rehearse overloading giving too much information interpolated activity activity between presentation of information and recall
Companion website: Forgetting in short-term motor memory Failure to rehearse Length of retention interval i.e. time between first and second performances of the movement the greater the retention interval the greater the amount of forgetting after about 80 s there is almost complete forgetting Interpolated activity When an old movement negatively affects performance of a new movement we call it proactive inhibition When a new movement negatively affects performance of an old movement we call it retroactive inhibition Retroactive inhibition does not occur if the old skill is well-learned
Companion website: Remembering in short-term motor memory Rehearsal is vital We remember location better than distance Interpolated activity can aid retention When an old movement positively affects performance of a new movement we call it proactive facilitation When a new movement positively affects performance of an old movement we call it retroactive facilitation
Companion website: Long-term memory Rehearsed information from STM is passed to LTM Stages in memory formation in LTM Encoding Two substages, acquisition - registering and sensory analysis of information consolidation - creation of a stronger representation Storage The creation and maintenance of a permanent record Retrieval Using the stored information to repeat a movement or recall facts LTM has no capacity limitations
Companion website: Forgetting in long-term memory Some argue that we do not forget There may be some temporary difficulty with recall Decay theory Failure to practise leads to loss of memory trace ‘use it or lose it’ Craik and Lockhart’s (1972) levels of processing model Consolidation and storage are aided by the depth at which the learner understands the information
Companion website: Forgetting and remembering in long-term motor memory LTMM has no capacity limitations Decay theory is well supported Levels of processing model is well supported Nature of the task is a factor Continuous skills are better retained than discrete and serial This is probably due to the repetitious nature of continuous skills, i. e., inherently more practice Some evidence to show that serial skills are remembered better than discrete Patterning phenomenon affects forgetting in LTMM we forget the timing of a movement before the sequencing and spatial organization Overlearning phenomenon affects retention in LTMM Even when we have learned a skill, we need to go on practising it
Companion website: Declarative long-term memory Also known as explicit memory It is consciously encoded and recalled It is subdivided into episodic and semantic memory Episodic memory contains personal experiences Semantic memory refers to knowledge or facts about things like how to multiply or divide, the rules of grammar and how to perform specific skills
Companion website: Non-declarative long-term memory Also known as implicit memory It holds subconsciously or implicitly learned information It is sub-divided into four domains Classical conditioning Non-associative learning The perceptual representation system (PRS) Identifies and responds to situations of which it has a great deal of experience It is responsible for quick responses to situations and quick decision making Procedural memory Memory for a vast amount of subconsciously acquired information both cognitive and motor
Companion website: Regional brain functions and memory The brain regions initially encoding information will depend on the type of information, visual, auditory, verbal, motor or emotional The right hemisphere is more involved in encoding spatial information and the left verbal or verbalizable information There is a great deal of bilateral encoding For declarative information, consolidation appears to be primarily undertaken by the hippocampus and, to a lesser extent, the thalamus Once information has been encoded, it is stored throughout the neocortex, which consists of the outer layers of the cerebral hemispheres The position of any specific memory will involve the regions that originally encoded the information and regions associated with these areas Formation of memories comes about by the strengthening, over time, of synaptic (the region between two neurons, across which neurotransmitters pass) connections between neurons - this is called long-term potentiation (LTP) Increased neurotransmitter synthesis and release at the synapse, synaptic pruning (the removal of synaptic connections between neurons which are not used) and neurogenesis (formation of new synaptic connections) form a process called neural plasticity or neuroplasticity
Companion website: HIPPOCAMPUS AMYGDALA HYPOTHALAMUS RETICULAR ACTIVATING SYSTEM Hippocampus plays a major role in the consolidation of declarative memory
Companion website: Development and memory The cellular changes resulting in facilitation of synaptic connections is on-going throughout life but is particularly prominent in childhood the child’s brain is well-endowed with nerve growth factors or neurotrophins, which are proteins that aid neurogenesis and neuroprotection In STM, we see instinctive chunking at about 7 years of age adult-type rehearsal at around 9 years According to Pascual-Leone (1970) the child’s functional mental capacity increases steadily up to 14 years Neurogenesis continues even into old age but only if the individual is active physically and/or mentally