PSYC306 - The Aging Brain

Suggested mechanisms involved in causing impairment within WM & LTM

Reduced Attentional Resources (Craik & Salthouse, 2000)

• Attentional resources; the ability to pay attention to what we are being asked to do both socially and cognitively
• Reduced processing resources are suggested to account for decline in WM
• Deficits are profound in tasks which require high levels of concentration, wheras tasks that do not demand alot of attention, mainly unconscious, remain largely unaffected
• WM tasks involve divided attention, therefore strain on the system may causes deficits
  • -ve, more descriptive than empirically based
  • -ve, attentional and processes resources are poorly defined
  • +ve, neurophysiological correlations (McDowd & Shaw, 2000), higher levels of cognitive arousal are shown for more cognitively demanding tasks which highlights that brain may have to work physically harder to complete difficult tasks. Patterns may be due to difficulty or due to attention required to complete task
  • -ve, disagreement on how long episodic memory are stored in hippocampus. They are hippocampul dependant, stored for a short time then transferred to the neocortex

Effortful Retreival

• Certain types of memory are more difficult to retreive than others
  e.g. recall memory is more difficult to retreive than recognition memory, meaning you are more likely to easily recognise someone than to remember specific details about them i.e. their name

• LTM is hierarchial meaning that information stored in memory lower in the hierarchy is more difficult to retreive
  e.g. it is more difficult to retreive episodic memory as it is lower in the hierarchy (Conway, 2005)
  Those memories lower in the hierarchy require a more effortful search in order to retreive the information stored within them.
  

Speed of Processing (Craik & Jennings, 1992)

• Cognitive processing speed is a measure of cognitive efficiency and proficiency

• Measured using tasks that require little conscious thought, often automatic, easy and over-learned processes. A measure of how quickly older adults can do what is asked and how they act upon what is asked.
• Age produces a general decline in speed of cognitive processing
  e.g. evidence is taken from mean response times, older adults response times are on average longer compared to younger adults completing the same task
• Age is related to speed memories and memory…