Birth cohort differences in fluid cognition in old age: Comparisons of trends in levels and change trajectories over 30 years in three population-based samples.

Abstract

Later-born cohorts of older adults tend to outperform earlier born on fluid cognition (i.e., Flynn effect) when measured at the same chronological ages. We investigated cohort differences in level of performance and rate of change across three population-based samples born in 1901, 1906, and 1930, drawn from the Gerontological and Geriatric Population Studies in Gothenburg, Sweden (H70), and measured on tests of logical reasoning and spatial ability at ages 70, 75, and 79 years. Estimates from multiple-group latent growth curve models (LGCM) revealed, in line with previous studies, substantial differences in level of performance where later-born cohorts outperformed earlier born cohorts. Somewhat surprisingly, later-born cohorts showed, on average, a steeper decline than the earlier-born cohort. Gender and education only partially accounted for observed cohort trends. Men outperformed women in the 1906 and 1930 cohorts but no difference was found in the 1901 cohort. More years of education was associated with improved performance in all three cohorts. Our findings confirm the presence of birth cohort effects also in old age but indicate a faster rate of decline in later-born samples. Potential explanations for these findings are discussed.

Gender Differences in Cognitive Performance in Old Age

“…This has been found across ages and countries (Flynn, 1987) and replicated in several studies (e.g. Karlsson, Thorvaldsson, Skoog, Gudmundsson, & Johansson, 2015;Sacuiu et al, 2010;Schaie, 2005). Yet, this trend has not been confirmed in studies that modelled cognitive performance conditioned on mortality.…”

Is the prevalence of psychosis in the very old decreasing? A comparison of 85‐year‐olds born 22 years apart

“…Our findings should be seen in light of previous findings from the Gothenburg H70 Birth Cohort Studies that suggest that later‐born birth cohorts have better health , are more engaged in leisure activities , have better cognitive functioning , lower prevalence of cardiovascular disorders , and higher sexual activity . All these findings may be attributed to the large changes that occurred in prenatal and perinatal care, educational levels, nutrition, life conditions, general attitudes towards ageing, health care, and medical treatment, all of which may affect brain health during the 20th century .…”

Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam

“…Evidence on cohort differences in cognitive aging is mixed and depends on several factors such as the cognitive domains assessed, participants’ age range, the number of years between birth cohorts, and whether studies examined cohort differences in levels or trajectories of cognitive performance. Previous studies that investigated birth cohort differences in level of cognitive performance in late life found better performance in a later born cohort (1926–1948), compared with an earlier born cohort (1900–1925) in memory, verbal, and spatial ability, but not in processing speed at age 67.5 ( Finkel, Reynolds, McArdle, & Pedersen, 2007 ); better performance in the 1914–1948 cohort compared with the 1886–1913 cohort in spatial orientation, word fluency, inductive reasoning, and verbal meaning, but not in numeric ability at age 70 ( Gerstorf, Ram, Hoppmann, Willis, & Schaie, 2011 ); better performance in the 1908–1940 cohort compared with the 1893–1923 cohort in reasoning, spatial orientation, list recall, and test recall, but not in vocabulary at age 74 ( Zelinski & Kennison, 2007 ); better performance in the 1932–1946 cohort compared with the 1910–1924 cohort in list recall, visual recall, and visual learning at age 61–75 ( Baxendale, 2010 ); better performance in logical reasoning and spatial ability in more recent cohorts born in 1901–1902, 1906–1907, and 1930 and measured at age 70 ( Karlsson, Thorvaldsson, Skoog, Gudmundsson, & Johansson, 2015 ); better performance in processing speed, executive function, letter fluency, and category fluency in the 1932–1943 cohort compared with the 1922–1931, 1912–1921, 1902–1911 cohorts aged 65 and older ( Dodge, Zhu, Lee, Chang, & Ganguli, 2014 ); better perceptual speed performance at mean age 75 in the 1925–1948 cohort compared with 1901–1922 cohort ( Gerstorf et al, 2015 ); better performance on the Mini-Mental State Examination (MMSE) and on a composite of five aging-sensitive cognitive tests in the 1915 cohort assessed at age 95 compared with the 1905 cohort assessed at age 93 ( Christensen et al, 2013 ).…”

“…On the contrary, other studies found that later born cohorts showed steeper cognitive decline. Compared with the 1901 cohort, the 1906 and the 1930 cohorts showed steeper decline in spatial ability, and the 1930 cohort showed steeper decline in reasoning ability between age 70 and age 79 ( Karlsson et al, 2015 ). Also, compared with the 1893–1923 cohort, the 1908–1940 cohort showed steeper decline in text and list recall between age 77 and age 86 ( Zelinski & Kennison, 2007 ).…”