Chapter 7 Cognition and Aging
Seattle Longitudinal Study variables that reduced the risk of cognitive decline in older adults
Absence of cardiovascular risk factors ‒High socioeconomic status ‒Involvement in a complex and intellectually stimulating environment ‒A flexible personality style ‒A high cognitive ability of one's spouse ‒Maintenance of high levels of processing speed
process of producing lanuage
Choose the meaning (semantics) that we want to say Choose the correct words (lemma/lexicon) that we need Organize those words (grammar/syntax) Connect the appropriate sounds to those words (phonological) Map the sounds onto the motor pathway (articulation) Perform the motor movements
The disconnection between procedural and episodic/semantic memory
Clive Wearing is a British musicologist, conductor, tenor and keyboardist ‒ He contracted herpesviral encephalitis, a herpes simplex virus that attacked his central nervous system ‒ Herpesviral attacks the temporal lobes - the seat of episodic and semantic memory (remember the hippocampus?) Astoundingly: his vocabulary is still huge, his sentences are complex
wisdom and aging
Concept of wisdom varies across cultures and it is very difficult to define. Little evidence for a relationship between wisdom and aging.
Intelligence: traditional conceptualization
Crystallized: Knowledge accumulated and solidified across the life span, based on life experience. Fluid: The ability to change, adapt, and learn within a novel experience. The ability to apply logic, solve problems, and identify patterns within a new experience.
processing speed
Declines in processing speed begin in the 30s and continue on throughout the life span. Salthouse's (1996) processing speed theory posits that older adults struggle in two main mechanisms: limited time and simultaneity. Limited time: Older adults struggle to perform later operations because a majority of their processing time is spent on earlier operations. This therefore limits and/or restricts their time for total processing of information.
Memory
Dependent on processing speed, selective attention, and organization of material to learn. Declarative memory: ‒Episodic ‒Semantic Nondeclarative memory: ‒Procedural learning, priming, classical conditioning Prospective memory: Remembering to do something in the future
Assessing Attention
Different neuropsychological tests to target aspects of attention ‒Test of Sustained Selective Attention: 8 min computerized auditory sustained attention test ‒Test for Divided Attention: 9 mins long ‒Trail Making Test ‒Attentional Capacity Test ‒Continuous Performance Tests
assessing executive function
Executive Function questionnaire (subjective) ‒Do this in class Multiple Errands Test ‒Requires specific task set-up Verbal Fluency Tests ‒Letter; Category Clock Drawing Tests Stroop Test (colors in different colors) Wisconsin Card Sorting Test
Semantic Memory
General fund of information, such as language and facts. Declines with aging, and may lead to declines in word-finding. Episodic memory declines gradually over lifetime and semantic memory declines mostly in late life.
Executive Functioning
Higher order cognitive skills that encompass a broad range of abilities. Include planning, organization, cognitive control, set shifting/mental flexibility, multitasking, concept formation, problem solving, and abstract reasoning. It also includes the ability to control behavior and resist impulsive actions, resulting in appropriate social interaction. This requires higher level cognitive processing such as the ability to self-monitor, reason, solve problems, maintain cognitive flexibility, organize, and plan.
slip of the tongue
In a slip of the tongue, the speaker mis-produces one or more sounds in an intended word: saying "coffee cot" instead of coffee pot saying "take the hands out of the guns of people" instead of "take the guns out of the hands of people" Older adults much more likely to commit these types of errors
impact of cessation of driving
Increased transportation burden on family and caregivers, particularly in rural areas. Poorer health, higher rates of depression and institutionalization, increased mortality among older adults that stopped driving. Loss of independence and freedom. Older adults may fear loss of independence more than they fear death.
Intelligence: multiple abilities
Initial inquiry into cognitive functioning focused primarily on evaluating cognition as a single construct, such as "intelligence" or general intellectual functioning (Spearman's "g"). As knowledge of the complexities of brain functioning has increased, the concept of a unitary construct to describe the totality of an individual's functioning has fallen out of favor (Lezak et al., 2012).
Language production
Language production is an extraordinary skill that allows a speaker to retrieve words from a lexicon of 50-100,000 words and speak them at a quite normal rate of 2 to 4 words per second. Errors in word production occur rarely, once or twice in 1,000 words
Most dangerous driving situation
Making turns across opposing traffic at intersections Merging from a yield lane Changing lanes on a highway Related to changes in visual attention and processing speed. Increasingly difficult on busy streets or streets with a high number of visual distractors (e.g., billboards, businesses, multiple intersecting streets, and so forth).
Assessing memory
Many, many different neuropsych tests for assessing memory ‒We used Rivermead test often in the clinic
procedural memory
Memory for how to complete various motor tasks (e.g., typing on a keyboard, tying shoelaces, driving a car with manual transmission). Increases with time and largely unaffected by aging.
episodic memory
Memory of personally experienced events. Declines with age more than other types of memory. Encoding, storage, or retrieval may cause loss of episodic memory. Memory for recent events is more impacted than memory for events long ago.
Driving and Aging
Older adult drivers represent the second age group most likely to be involved in accidents. -The rate of traffic accidents is higher among drivers aged 16 to 19 than for any other age group. ‒Per mile driven, drivers aged 16 to 19 are nearly three times more likely than drivers aged 20 and older to be in a fatal crash. The ability to drive is paramount to independence and mobility. However, the risk of being injured or killed in a motor vehicle accident increases with age, due to ‒Increased crash risk ‒Greater physical frailty when exposed to a crash
protective factors
Older adults are more likely to wear seatbelts than younger adults. Older adults more likely to refrain from driving in bad weather or at night. Older adults drive fewer miles than younger drivers. Older adults have the lowest rates of accidents while driving under the influence.
older adults and language
Older adults know more words than young adults, but they are more likely than young adults to experience difficulty producing a specific word Tip of the tongue phenomena: "I know the word, I know the sounds of the word, but I can't find the right word". - more common in elderly Older adults make more errors in naming pictures of objects or actions than young adults but this difference does not become significant until older adults are in their 70's Older adults tend to make more phonological (sound) errors than semantic (meaning) errors For instance, if an older adult can't find a word (ex. Elephant) and you were to cue them with the sound that the word started with ("starts with el-"), they'd respond much better to this cue than if you were to tell them the category that the word is in ("this is a pachyderm")
written language and older adults
Older adults reported that they can no longer spell words they once knew how to spell, and despite their higher vocabulary and education in these studies, they were more likely than young adults to misspell words they read or heard Older adults regularized irregularly spelled letter combinations more than young adults, e.g., calendar calender, but only the old-old group (M age = 77 years) misspelled regularly spelled combinations, e.g., calendar kalendar (MacKay & Abrams, 1998; MacKay, Abrams & Pedroza, 1999) Cortese, Balota, Sergent-Marshall, and Buckner (2003) reported that older adults made more errors than young adults in spelling spoken homophones with heterogeneous spellings, e.g., vein, capitol, and were more likely to produce a spelling that corresponded to the dominant meaning but was a non-dominant spelling for that sound (e.g., vein).
divided attention (multitasking)
Older adults struggle more with multitasking, or attending to multiple tasks simultaneously, compared to younger adults. Older adults also show a decline in working memory on tasks that involve manipulating information while it is being stored in memory. Older adults have a decreased ability to refocus after being disrupted from a task
executive functioning: positive changes
Older adults tend to have a better ability to attend to positive emotions than younger adults. Older adults may be more capable of solving some social problems because they are more likely to incorporate emotion-regulation strategies.
executive functioning in aging
Older adults tend to think more concretely than younger adults. Older adults have more difficulty suppressing automatic responses in novel situations. Changes in volume of the frontal lobes can be associated with an older adult's inability to inhibit undesired actions such as talking excessively about a topic or making socially inappropriate comments.
Fluid intelligence
Peaks in the 30s and then declines at an estimated rate of −0.02 standard deviation per year (Harada et al., 2013). Older adults are challenged more in response to novel situations and in their ability to gather and organize new learning as compared to younger adults.
relationship of speech recognition and auditory sensory and perceptual change
Presbycusis is age-related hearing loss, influenced by both physiological and environmental factors, and is characterized by bilateral loss of higher frequencies, the frequencies important for speech In the Framingham Heart Study, pure tone thresholds for 1,662 participants aged 63-92 years predicted correct word recognition Large relationship between acuity and speech recognition Older adults with hearing loss are poorer than normal hearing older adults at identifying speech stimuli ranging from syllables to sentences Older adults exhibit other visual processing deficits that are relevant to reading: retinal blurring reduced accuracy of voluntary saccadic eye movements reduced retinal illumination and loss of contrast sensitivity
examples of everyday activities involving attention and processing speed
Reading Participating in a conversation Comprehending and following the plot of a movie or story Driving Following directions for how to get to a destination Keeping up with automated telephone operating systems Avoiding an accident or a fall Using a computer, tablet, or smart phone Counting out change Cooking a complex meal Crossing a street Parking a Car
decline in executive functioning
Reductions in judgment such as inhibiting inappropriate behaviors or statements, or falling for phone and e-mail scams ‒Dressing inappropriately for the weather or different types of occasions ‒Poor planning of events such as meals, parties, or errands
ways to enable older adults to continue driving safely
Speed of Processing Training Modifying roadways: ‒Improve lighting of signs ‒Increased text size of signs ‒Signs placed at strategic places to read them (e.g., 2 miles before an exit) Modifying time estimates of perception and action (e.g., how long to make a yellow light last) Self-driving cars
CASE STUDY: Joshi immigrated to the United States 40 years ago and now, as a 72-year-old, lives with his son and his son's family. They have recently noticed Joshi trying to leave the house, in Minnesota, in midwinter without a jacket or hat. Furthermore, although he has always done his own grocery shopping, he now often comes back with half of his list unfilled and extraneous items, such as seven hairbrushes, when he has been bald for 20 years, in their place What part of cognitive functioning is failing in Joshi's case? What other changes might then be expected from Joshi?
Suggested response: Joshi is showing a significant decline in executive functioning, those higher order cognitive skills that include planning and abstraction. He goes out inappropriately dressed for the weather and struggles to follow a list that he himself created. This part of fluid intelligence declines with the performance of the frontal lobes. Suggested response: Any other executive functioning may start to show serious decline. This could manifest as new difficulties making inappropriate remarks, spending lavishing beyond his means, and becoming unreliable with meeting times.
CASE STUDY Darlene, 83, lives alone in her home of 50 years. Her daughter has noticed that, while her mother can still navigate the home with ease and find items readily, Darlene has increasing difficulty in describing what she is doing or looking for Why can Darlene still find her way around her home so well in spite of her verbal deficit? What is probably going wrong to cause Darlene's difficulty describing her plans?
Suggested response: The occipital lobes of the brain, responsible for visuospatial skills such as navigating a familiar environment, show little change with normal aging, so Darlene's sustained ability to move around her home is not surprising, even if some other decline in brain function is causing difficulty with speech. Suggested response: Working memory usually declines as people age, so Darlene is probably showing a pronounced decline in this part of her memory. This, in turn, reduces the ability to find the words one is seeking or to express thoughts fluently.
Complex attention
Sustained attention, divided attention, selective attention, processing speed
Mandatory Retirement Ages
The Age Discrimination in Employment Act of 1967 (ADEA) prohibits forced retirement for those older than 40. However, there are a few professions that are not able to employ older adults indefinitely, because of public safety concerns. These include pilots (65), air traffic controllers (56, with exceptions up to age 61), and federal law enforcement officers (57 or later if less than 20 years of service). Specifically aimed at professions that are considered to require high levels of physical and mental skill and/or are highly dangerous. Aging affects the level of processing speed necessary for these jobs to be performed safely. Mandatory retirement laws are controversial as they do not allow for individual variability and are typically based on limited scientific data.
simultaneity mechanism
The inability to hold onto earlier processing information to be used to complete later processing.
Language
Whereas normal aging impairs specific aspects of language production, most core language processes are robust to brain aging. Older adults even show improvement in narrative discourse. Older adults are often thought to tell more interesting stories and exhibit more extensive vocabularies than younger adults. Even though word-finding difficulties might increase or hearing loss might impact communication abilities.
inhibitory deficit hypothesis
aging reduces ability to tune out irrelevant information The inhibitory deficit can also lead to greater proactive interference, or difficulty with learning something new due to old learning interfering with the new information being encoded.
dysfluencies
another type of speech error that interrupt the flow of speech and appear to indicate a word retrieval problem In describing a picture or other stimulus, older adults tend to produce more lexical fillers (e.g., you know), non-lexical fillers (e.g., um), word repetitions (e.g., just on the left left side), lengthy pauses and empty words than young adults
useful field of view
area of the visual field that can be processed in one glance
language
expressive and receptive
executive function
planning, decision making, responding to feedback, overriding habits/ inhibition, mental flexibility
social cognition
recognitin of emotions, ability to consider other people's mental state or experience
crystallized intelligence
remains stable over time and can even gradually improve throughout an individuals 60s and 70s as more information is accumulated with age older adults can even outperform younger adults in tasks involving crystallized intelligence
Visuospatial ability
tendds to remain intact with normal aging, consistent with occiptal lobes remaining intact
Common Cause Hypothesis
the link between sensory processes and cognitive functioning becomes stronger in older adulthood than it was earlier in life proposes that cognitive changes occur with age because of an overall weakening of the integrity of the brain and the nervous system based on studies showing a decline in cognitive abilities related to declines in other systems, such as motor and sensory functioning
perceptual motor
visual perception, visuo-constructional, perceptual-motor, praxis, gnosis