Chpt 6 Adulthood
Brain's default network
A circuit in the brain that is active when the brain is at rest while processing internal stimuli. Includes hippocampus, parts of prefrontal cortex, parietal lobe, temporal lobe, and part of cingulate cortex involved in visualization. Becomes deactivated during tasks involved in working memory; and other areas become activated. Older adults show decreased activation of default network and are less able to deactivate during memory tasks. However, high-functioning older adults may be able to draw on default network during working memory tasks.
Semantic Memory
Ability to recall word meanings and the factual information. There are no declines in normal older adults Older adults are able to remember word meanings and a broad array of factual information on a comparable level with younger adults.
What are the causes of crashes among older adults?
Are more likely to crashes at intersections where driver is making a turn that takes them across traffic. Have more difficulty when required to merge /yield to oncoming traffic. Are able to self-regulate behaviors to compensate for changes experienced in visual and cognitive abilities. Do not drive at night or on interstate highways or situations in which they must make risky left hand turns.
What lab task is used to assess working memory?
Assessed using "N-back" task. Commonly used working memory test that requires participants to repeat the "nth" item back in a list of items presented to them in a serial order.
Reaction Time
Basic element of processing speed. Measured by asking participants to complete an action (e.g., pushing a computer key when the screen flashes a target). Reaction time of a young adult is lower than older adults. People vary in rate of slowing in reaction time. Net effect of changes are negative across adulthood (especially for choice reaction time tasks).
Retrieval-Induced Forgetting ("Tip of the Tongue" phenomenon)
Being unable to remember information that a person knew at one time in the past. Observed more in older adults in both laboratory everyday situations. Young adults occasionally experience this effect when trying to retrieve an abstract word; older adults are more likely to forget a person's name. Declines experienced by older adults may be due to age related neural declines in the area of the brain used for phonological production.
Memory Controllability
Beliefs about the effects of the aging process on memory, such as the extent to which the individual believes that memory decline is inevitable with age. Older adults who rely heavily on identity accommodation are more likely to hold negative beliefs about their ability to control their memory as they age. This In turn, contributes to poor performance on memory tasks. Individuals who believe that they can control their memory are more likely to take advantage of strategies that improve memory performance.
Types of Attention Tasks: Visual Search Tasks
Both younger and older adults perform less efficiently on conjunction search tasks than they do on simple search tasks (but cost of performance is higher for older adults) Older adults have greater experience in making decisions in real life settings which benefits them when scanning environments When compared to younger adults on a search tasks that included context to guide their attention, older adults were more likely than younger adults to benefit from background cues. Older adults can benefit from training that gives them practice and guidance in performing even very difficult conjunction searches
Memory and Health Related Behaviors
Cigarette Smoking Poorer memory among smokers and former smokers Consumption of fish "Lower rate of cognitive decline in fish eaters " Dietary intake of "Vitamins B12, B6, and folate Homocysteine, or meat (negative) Flavonoids including chocolate" Ginko Biloba No benefits Exercise Positive benefits of aerobic exercise and strength training Metabolic Factors Lower levels of IGF-1 associated with better memory Emotions Stress and depression can interfere with memory performance Sleep Related to better memory but only in young adults
Components of working memory
Components of working memory (Badeley, 2003) 1Phonological loop: Holds auditory memory. 2Visuospatial scratch pad: Holds memory for information that is seen. 3Episodic buffer: Responsible for recalling information in long-term memory by bringing it temporarily back into working memory. 4Central executive: Integrates the other three components of working memory.
Processing speed and attention
Deviations of dots from the diagonal line shows the extent to which older adults are disproportionately slower as the task becomes more challenging for young adults.
Which age group(s) have the highest fatality rates? for driving
Highest fatality rates are among younger adults 16-19 & 20-24 years old
Inhibitory Deficit Hypothesis
Hypothesis suggests that aging reduces the individuals ability to inhibit irrelevant information. Widely supported by studies based on psychological and electrophysiological methods. Older adults are less able to block out distracting stimuli when completing a task (based on ERP) Experience deficits in the prefrontal cortex). Older adults are less likely to suppress irrelevant information; results in both increased frontal activity and poor memory performance compared with younger adults (based on EEG). Middle age and older adults perform best when they have few distractions.
Remote Memory
Involves the recall of information from the distant past. MYTH: Older people can remember information for many years in the past better than they can remember more recent information. EXCEPTION: Autobiographical memory [or the recall of information from a person's own past]. Many individuals experience a reminiscence bump of very clear memories for the ages of from about 10 to 30 years (effect is particularly strong for happy memories).
Working Memory
Keeps information temporarily available and active in consciousness.
Implicit Memory
Long-term memory for information that people acquire without intending to do so. Does not appear to be affected by the aging process. How is it tested? Presenting participants with a task that involves manipulating but not remembering information. E.g., participants are presented with a list of words and asked to place them into categories but not recall them. Later are asked to remember the words previously instructed to only categorize. Priming: show information that leads participants to think of certain things, topics, or situations. E.g., participants see a list of words containing the word :Apple". Later are shown the word fragment such as "A _ P_ _" and asked to fill in remaining three blanks.
Choice reaction task
Make one response for one stimulus and another for a different stimulus
Simple reaction time task
Make response as soon as target appears
How is Inhibitory control measured?
Measured using Stroop Test. Response time and accuracy compared when color and word match with performance when color and word do not match. Good inhibitory control = able to turn off naming of color based on word
Episodic Memory
Memory for events that took place in the past. Older adults experience impairments both in encoding and retrieving information. Depends on the integrity of connections among frontal cortex, temporal and parietal lobes and areas of subcortex (thalamus) Memory changes in these regions due to WMH. Structural changes in the brain compensated by heightened activation of the prefrontal cortex in normal aging. Scaffolding theory: Older adults are able to recruit alternative neural networks as needed by task demands to make up for losses suffered elsewhere in the brain.
What are the causes of crashes among younger adults?
More likely to drink and drive. More likely to drive while distracted.
Advanced Cognitive Training for Independent and Vital Elderly [ACTIVE] study
N=2800 adults, ages 65-94 years. 2 year period, 10 sessions, 1 hour each, 5-6 weeks Memory, reasoning, or speed of processing Improvements shown by 87% (reasoning), 74% (speed), and 26% (memory) Gains maintained for 2 years (and counting).
Scaffolding theory
Older adults are able to recruit alternative neural networks as needed by task demands to make up for losses suffered elsewhere in the brain.
Stereotype Threat
People perform in ways consistent with negative stereotypes of the group to which they see themselves as belonging. Research suggests that an older adult's self identification as old contributes to lower memory test scores. Because older adults are stereotyped as having poor memory this belief causes poor performance. Identification with negative images of aging interferes with memory performance in older adults by lowering their feelings of self efficacy. Consequently, older adults become less able to take advantage of mnemonic strategies.
General slowing hypothesis
Proposes that increase in reaction time reflects general decline of info processing speed within the nervous system of the aging individual.
Age Complexity Hypothesis
Proposes that through a slowing of central processes in the nervous system, age difference increase as tasks become more complex and the older adult's processing resources are stretched more to their limit.
Flashbulb Memory
Recall of important and distinctive events that stand out from other memories of past events When older adults form such memories they are likely [as younger adults] to recall them correctly.
Procedural Memory
Recall of the actions involved in particular tasks. Holds up well with age Contributes to the ability of older adults to compensate for some of their loss of speed and working memory in diverse areas
Memory training studies show benefits for older adults
Strategy training Support during encoding (e.g., additional cues, "deep processing") Training that taps into areas of expertise Method of loci training altered white matter density Virtual reality helped older adults by simulating walking through various destinations while playing soothing music.
Conjunction search
Target differs from distractors in more than one way (involves serial processing)
Simple search
Target differs from other stimuli by only one feature (involves parallel processing)
Memory Self-Efficacy
The degree to which an individual believes that he/she can successfully complete a memory task. Higher memory self-efficacy is, the greater the likelihood that individual will perform to maximum ability Decreases with increasing age. Lower memory self-efficacy may turn into a self-fulfilling prophecy.
Prospective Memory
The recall of events to be performed in the future. Older people appear to have more prospective memory slips than do younger adults. The more heavily a prospective memory task involves planning and the frontal lobe, the disadvantaged the older adults seem to be. If aware of prospective memory problems, older adults can take advantage of reminders (effective for adults in the young-old age category).
Source Memory
The recall of where or how a person acquires information. Older adults Have greater difficulty on source memory tasks when they must judge where they saw an item on a previous occasion. Are more susceptible to false or illusory memories in which they say they remember something they never happened. False memories measured using the Deese-Roediger-McDermott [DRM] paradigm. Few people are immune from this effect but when warned, younger participants are better able than older adults to avoid the false memory implantation
Model of Driving Self Regulation
Whether older adults continue to drive depends on a number of psychological factors, including feelings of self-confidence, desire to get out of the home, need for independence, importance of driving to self worth, and perceived health. Socio-cultural factors include whether an older adult can get rides with others, has access to public transportation, and lives alone or with others.
Attentional Resources Theory
regards attention as a process reflecting the allocation of cognitive resources. Older adults have greater difficulty on attentional tasks because they have less energy available for cognitive operations than do their younger counterparts. Tasks that require high attentional demands are subject to reduced performance among older adults, compared with tasks that require little attention that remain intact. Little empirical research is available to support this theory
Distractor
stimuli that do not fit criteria for target
Inhibitory control
turning off one response while performing another
