Thinking abilities in later life

Introduction: Researchers compared adults of different ages on two kinds of thinking tests at one point in time.

Participants: 1,200 adults aged 20 to 79 in Sweden, 200 in each ten-year age group (half women), chosen at random from the national population register. Race/ethnicity was not reported.

Method: All participants were tested in 2022. A vocabulary test asked them to define 40 words. A puzzle test asked them to find the missing piece in visual patterns they had never seen before, with 30 puzzles and a 15-minute time limit.

Results and Discussion: Mean vocabulary scores (out of 40) were: age 20–29, 24; 30–39, 27; 40–49, 29; 50–59, 30; 60–69, 31; 70–79, 30. Mean puzzle scores (out of 30) were: age 20–29, 22; 30–39, 21; 40–49, 19; 50–59, 17; 60–69, 14; 70–79, 12. Older age groups had, on average, completed fewer years of schooling.

Introduction: Researchers tested the same adults repeatedly over 28 years to see how their thinking changed as they aged.

Participants: 640 adults in Seattle, Washington, aged 32 to 40 when first tested in 1990 (54% women). The 412 participants who were still taking part in 2018 were 60 to 68. Participants who dropped out had, on average, slightly lower scores when they started. Race/ethnicity was not reported.

Method: Every 7 years, participants took a different set of 30 visual pattern puzzles of the same difficulty, with a 15-minute time limit, and a 40-word vocabulary test.

Results and Discussion: The same people's mean puzzle scores were 21.4 at the first test and 19.6 at the last, a decline of 1.8 points over 28 years, with most of it in the final 7 years. Their vocabulary scores rose slightly, from 28.1 to 30.5. The researchers noted that differences between age groups in studies like Source 1 may be larger partly because people born earlier grew up with less schooling.

Introduction: Researchers tested whether a training program can improve how fast older adults process information.

Participants: 160 adults aged 65 to 80 (98 women and 62 men) living independently in Boston, Massachusetts, none with a diagnosis of dementia. Race/ethnicity was not reported.

Method: Participants were randomly assigned to 10 weeks of either a computer program in which they had to identify quickly flashed objects, with the task getting harder as they improved, or weekly crossword-puzzle sessions for the same amount of time. Before training, right after it and two years later, participants were tested on how quickly they could identify flashed objects and on everyday tasks, such as finding information on a medication label.

Results and Discussion: Right after training, the computer-program group identified flashed objects 30% faster than before, while the crossword group showed little change. Two years later, the computer-program group was still 18% faster than at the start. The two groups did not differ significantly on the everyday tasks at either time.