Role of lab experiments

Role of lab experiments

1. Cognition

   • Attention
     • sig impairments on attentional tasks that require dividing or switching of attention among multiple inputs or tasks. Issues with selective attention: negotiating busy road junction = no age effect for simple features but there is for conjunction searches: longer reaction times, make more mistakes, increased distractions increase their reaction time and they have problems with inhibition of relevant information. divided attention impairments are significantly associated with increased automobile accidents in older adults (McDowd & Shaw, 2000; Park & Gutchess, 2000) - highlighting an age-related decline in selective attention.
   • Memory
     • OA produce sig more pointing errors than YA in self-ordered pointing tasks, suggesting an age-related decline in working memory. Naveh-Benjamin (2000): asked participants to study & assess pairs of items, then given a test of item information (recognition of previously seem items) & a test of association (previously seen pairs, and pairs previously not seen in this combination). = OA were disproportionately impaired on the association test compared to the item information test - hightlight an age-related decline in episodic memory. Compared with their younger counterparts, older people recall fewer sensory, visual, and spatial details about the origins of their memories (Hashtroudi, Johnson, & Chrosniak, 1990) highlighting a decline in source memory. however, OA recall more than YA about their thoughts and feelings related to the source.
   • Executive functions & Inhibition
     • Research has shown that concept formation, abstraction, and mental flexibility decline with age, especially after age 70 (Lezak et al, 2012), as OA tend to think more concretely than YA (Salthouse, 2010; Singh-Manoux, 2012; Oosterman et al, 2010; Wecker et al, 2005). Tests such as Wisconsin Card Sorting Test (WCST) and the Tower of Hanoi have shown a age-related decline in executive functioning. tests such as the Hayling sentence completion test (Burgees & Shallice, 1997) have highlighted an age-related decline in inhibition.
   • Socio-emotional processing
     • Emotional processing, social behaviour and emotional regulation are believed to improve with age. Safeties (2004): OA score higher than YA do on facilitating, understanding, & managing emotions on the Mayer–Salovey–Caruso emotional intelligence test & are better at understanding emotions tests. Happé, Winner and Brownell (1998): ToM skills increased with age.
     • there are age-related declines in the processing of negative emotions on faces; OA are less accurate than YA at labelling sadness, fear and anger. Isaacowitz et al (2006) carried out an Eye-tracking study = OA showed a preference towards happy faces (as opposed to neutral), approaching sig, and OA showed a sig preference away from angry faces (as opposed to neutral), whereas there was no differential preferences in YA. Due to a adaptive positive bias?
       • Socioemotional selectivity theory (Carstensen, 1992; 19195; Carstensen, Isaacowitz, & Charles, 1999): perception of time is important in both the selection and pursuit of social goals. social motives fall into either those related to the acquisition of knowledge or those related to the regulation of emotions. When time is perceived as open-ended, knowledge-related goals are prioritized. In contrast, when time is perceived as limited, emotional goals assume primacy. = behavioural changes in old age do not simply reflect efforts to cope with loss, but rather reflect active adaptation to particular circumstances, social niches, and environments, which are inevitably framed by time.
   • Semantic memory, procedural & tacit knowledge
     • Park et al carried out 3 semantic memory tasks = a gradual increase in performance across age groups (20-92yrs) = semantic knowledge increases. And, procedural skills and tacit knowledge remain the same, if not improve, with age.

2. Methodological issues

   • "Normal"
     • misdiagnosed as cognitively normal during enrollment or develop cognitive impairment during. (I.e. dementia onset tends to be insidious, & early symptoms can be easily missed - Lezak, Howieson, Bigler & Tranel, 2012; Ross et al, 1997).
   • Longitudinal
     • subject to bias (populations will undergo attrition over time. those most likely to remain tend to be the healthiest, best educated, wealthiest, & have the highest scores on cognitive tests at baseline - Van Baijsterveldt et al, 2002). also subject to practice effects - Abner et al, 2012; Salthouse, 2010.
   • Cross-Sectional
     • cohort differences: culture, lifestyle, education, & requirements for success in life. one age cohort may perform very poorly on any given cognitive or neurological test compared to subjects from a different age cohort irrespective of cognitive capacity (Williams & Klug, 1996). Therefore, Cohort difs can confound cross-sectional studies by potentially overestimating effects of aging (Hedden & Gabrieli, 2004).
   • Selection Bias
     • Many potential participants decline enrollment (healthy, busy, or too ill -Minder et al, 2002). those with limited social or financial support and functional limitations less likely to enroll (Ford et al, 2008). = cannot be generalised.

3. Lab vs real life

   • labs may lack ecological validity; naturalistic shown an increase in prospective memory with age. paradox could be explained by many different variables: as motivation, control over memory cues, task absorption, & metacognitive awareness.
     • Schnitzspahn et al (2011): lab prospective memory experiment 20YA & 20OA (OA scored higher on Gc & YA scored higher on Gf). 3groups: documentary, magazine & cards - asked to remember to press a computer key at a specific time. naturalistic prospective memory task - to remember to send a SMS to the experimenter at specific times (Experimenter & self-selected times). All completed a 5-point Motivation scale and metacognition test. Lab experiment completed task absorption tests, & success on their lab task was measured, while naturalistic experiment competed measurements of daily activity absorption (stressfulness). = confirmed the paradox - age deficit in lab task related to higher task absorption and an age benefit in naturalistic task related to less daily activity absorption, higher motivation & better meta-cognition. Showing that extraneous variables influence task performance and prospective memory.

4. Fluid knowledge

   • abilities involving problem-solving & reasoning about things that are less familiar and are independent of what one has learned. includes innate ability to process & learn new information, solve problems, & attend to & manipulate environment (Elias & Saucier ,2006). i.e. Executive function, processing speed, memory, & psychomotor ability. Many fluid cognitive abilities, especially psychomotor ability and processing speed, peak in the third decade of life and then decline (Salthouse, 2012).
     • Salthouse et al (2011): analytical reasoning task (Gf) & a crossword puzzle (Gc) = analytical reasoning scores declined with age while ability to complete the crossword increased with age.

5. Gerontology: normal cognitive decline associated with aging. Geriatrics: decline caused by diseases

6. Crystallised Knowledge

   • skills, ability, and knowledge that is overlearned, well-practiced, & familiar (Lezak, Howieson, Bigler & Tranel, 2012). i.e. Vocabulary & general knowledge. remain stable or gradually improve per year through 6th & 7th decades of life (Salthouse, 2012). due to accumulation of information based on one’s life experiences therefore OA perform better at tasks requiring this.