3 types of memory
- Sensory memory
- Short-term memory (STM)
- Long-term memory (LTM)
- Sensory memory
brief, transient sensations of what has just been perceived
- -> information automatically and rapidly decays
- -> information first flows into this memory
- Short-term memory (STM)
temporary memory that can be maintained as long as it is rehearsed/consciously attended to
–> elements sensory information that are attended to are transitioned to STM
- Long-term memory (LTM)
memories can be retained for long periods, or permanently, without requiring ongoing maintenance/conscious attention
–> they go through processes in STM and in some cases are transferred into LTM
Iconic memory
critical for recognising and processing briefly presented information
Memory is limited
- in capacity
- to what we can pay attention to
Depth of processing
level of activity devoted to processing new information
- it refuted Atkinson and Shiffrin’s view that passive rehearsal alone is sufficient to transfer information from STM to LTM
- it enhances storage more, because it creates richer web of connections among stored memories, facilitating later retrieval
Baddeley’s working-memory model
it describes working memory as consisting of visuo-spatial sketchpad and a phonological loop, both controlled by a central executive and stored separately
Baddeley’s working-memory model
It makes two important types of distinctions
- It distinguishes between two processes
2. Its two buffers are material-specific
- It distinguishes between two processes
Baddeley’s working-memory model
between Manipulation and Maintenance
Manipulation:
- depends on central executive
Maintenance:
- requires rehearsal of information in two memory buffers
- Its two buffers are material-specific
Baddeley’s working-memory model
- -> one stores verbal material and
- -> the other stored object and location material
Visuo-spatial sketchpad (VSS)
- mental workspace for storing and manipulating both visual and spatial information
- it is limited in its capacity
Phonological loop (PL)
- it holds auditory memories, maintaining them by means of internal speech rehearsal
- internal/unspoken speech used during rehearsal is key to phonological loop and verbal working memory
- -> if internal rehearsal is disrupted, storage cannot occur
Central executive of working memory
for working memory updates it by receiving and evaluating sensory information, moving items into and retrieving them from LTM and deciding which memories are needed for which tasks
- keeping track of goals, planning how to achieve them, and determining priorities
- Central executive also allows us to inhibit a habitual response that was developed and shift our attention to an alternative, context-specific rule that we must remember
- -> f.e. Stroop task
Tower of Hanoi
solving it requires a lot of manipulation of working memory
Task switching
requires manipulation of working memory, because we put pay attention to ongoing task while monitoring external cues for information that may signal need to switch to another task
–> Wisconsin Card Sort Test
Damage to frontal lobes
shows deficits on all working-memory and executive-control tasks
–> in absence of an executive-control system, we are no longer guided by long-term goals or task-specific contraints
Mapping Baddeley’s model onto PFC anatomy
Dorsal and ventral regions of prefrontal cortex perform qualitatively different processes
Dorsolateral prefrontal cortex
Mapping Baddeley’s model onto PFC anatomy
Supports higher-order executive-control functions –> such as monitoring and manipulating stored information
Lesions to Dorsolateral prefrontal cortex
Mapping Baddeley’s model onto PFC anatomy
produce severe deficits in temporal ordering, which requires active manipulation of working memory
- patients may show impairments in delay-response tasks and connot determines which containers have already been emptied and which still have a reward
Ventrolateral prefrontal cortex
Mapping Baddeley’s model onto PFC anatomy
supports encoding and retrieval of information (passive rehearsal for maintenance), performing roles of visuo-spatial sketchpad (right) and phonological rehearsal loops (left) as proposed by Baddeley’s model
During encoding of new semantic information, left VLPFC can be dissected:
(Mapping Baddeley’s model onto PFC anatomy)
- anterior regions - activated during tasks involving semantic processing
- posterior regions - activated during phonological processing
Damage to left PFC
shows deficits to verbal working memory
–> language tends to be left-lateralised in the brain
Verbal working memory
the ability to remember something and to perform an activity using this memory
