Chapter 6 - the psychobiological process of memory Flashcards
Sensory Memory
Entry point for new information from our senses
Function: receive sensory info from the environment
Capacity: potentially unlimited
Duration: 0.2-4 seconds
Short Term Memory
Does not hold an exact replica of info
Allows us to actively manipulate or ‘work on’ information
Function: stores a limited amount of information for a short period of time, so it can be used or manipulated
Capacity: 7+- 2 items
Duration: 18-30 seconds (without rehearsal)
Long Term Memory
Relatively permanent store that can hold vast amounts of information for long periods of time
- Inactive
- Info is encoded
Function: information storage for a later period of time
Capacity: virtually unlimited
Duration: relatively permanent
Strengths of Atkinson-Shiffrin Multi Store Model
- highlights different stores and distinguishes between them
- provides a clear structure and process for how memory function, and explains forgetting
- supported by evidence of the distinction b/w stm and ltm
Limitations of Atkinson-Shiffrin Multi Store Model
- may be oversimplified, e.g. STM is more complex than the model suggests
- ignores other psychological factors (e.g. motivation)
- studies show that transferring info to LTM can occur without rehearsal
- doesn’t account for individual differences
Explicit (declarative) memory
memory that is consciously recalled
expressed in words
Semantic memory
facts or general knowledge
Episodic memory
personal experiences
Implicit (non-declarative) memory
memory that is unconsciously recalled
demonstrated through changes in behaviour
Procedural memory
Motor skills and actions
Classically conditioned memory
involuntary responses (motor or emotional)
Hippocampus
located within the medial temporal lobes
- encodes explicit memories
- transfers new LTMs into the neocortex for permanent long term storage
- plays a role in spatial learning and memory
Neocortex
The outer layer of neural tissue, part of the cerebral cortex which includes the 4 lobes
- Stores explicit memories in the area that they were first processed in
- when required, the separate parts are reconstructed into a single memory and are brought into conscious awareness
- LTP occurs every time the neural network is activated
Amygdala
almond shaped ball of neurons, attatched to the hippocampus
- encodes emotion component of explicit LTMs
- encodes memory of implicit, classically conditioned emotional respones
Basal ganglia
lies deep within the brain
- encodes, stores and retrieves implicit, procedural LTMs and simple CC motor responses
- coordinates smooth movement
- works with motor and prefrontal cortices to initiate or inhibit movements. (parkinsons patients often have damage to basal ganglia)
- forming implicit procedural memories associated w/ habits by associating movements w/ rewards or reinforcement
Cerebellum
Located at the base and rear of the brain
- encodes, stores and retrieves implicit, procedural LTMs and simple CC motor responses
- coordinates fine motor movements and balance
Autobiographical memories
A memory system involving ‘episodes’ from a person’s life, based on a mix of episodic and semantic memory
- episodic provides first-person experiential component
- semantic provides self knowledge including general event knowledge or personal facts without context
Possible imagined futures / episodic future thinking
projecting yourself forwards in time to pre-experience an event that might happen in your personal future
- ‘trying out’ different scenarios can guide future actions
The role of episodic and semantic memories in possible imagined futures
episodic provides episodic elements used to recombine and construct future events or scenarios
semantic provides a context or framework for constructing and organising future thinking
Alzheimer’s disease
a type of neurogenerative disease characterised by gradual widespread degeneration of brain neurons, progressively causing memory decline, deterioration of cognitive and social skills and personality changes
Alzheimer’s - memory loss progression
- trouble forming new episodic and semantic memories (due to hippocampus damage)
- trouble retrieving old episodic LTMs
- trouble retrieving old semantic LTMs
- loss of procedural LTMs
Amyloid Plaques
protein clusters form clumps OUTSIDE the neurons, inhibiting communication between neurons
Neurofibrillary tangles
protein build-up INSIDE neurons, inhibit transportation of essenial substances and results in neurons dying
Alzheimer’s changes in the brain
Reduced levels of NT: acetycholine (related to memory)
cortical shrinkage - as neurons become damaged and brain tissue shrinks and eventually dies (especially hippocampus)
Aphantasia
A phenomenon in which people are unable to visualise imagery
- would be able to state what an experience or event would involve, however unable to conceptualise it in their mind
- trouble retrieving autobiographical memory and episodic future thinking
