The evolution of a basic psychological process, such as memory, being very illustrative, there are many cognitive structures that can change significantly in old age. This change is usually characterized by a normal deterioration in certain functions – so that intelligence as we age could be affected – while others are preserved.
But, what happens to one of the most relevant cognitive processes of the human being? Does intelligence fade with age? Is an adult of fifty years less capable than his self of thirty? In this article we are going to explore what happens to intelligence as we age.
Findings from the cohort studies
The cohort studies, which follow the same sample over a long period of time, speak of certain variables that influence the consideration that intelligence is lost over the years. These variables are very relevant, since it is not necessary to rush to affirm anything without first knowing what may be motivating one or the other results.
In this way, there are four fundamentals related to intellectual functioning:
The importance of socioeconomic factors
The generational effects are greater than the effects of age in terms of intellectual functioning. There is no universal deficit pattern that has occurred in all ages and cultures, which can lead us to think that the socioeconomic factors, cultural, political, social and economic history of a country, education. .. all this has a greater impact in intelligence than the fact that one gets older.
When comparing different generations in the same chronological age, young people tend to have better results. Although we could conclude that young people are smarter than older people, this is undoubtedly incorrect. In recent decades there has been an increase in cognitive functioning that is explained by the increase in the supply of training or educational opportunities that people who are now older did not enjoy.
Variation in the enhancement of skills in generational change
Continuing with the idea of the importance of sociocultural factors, when comparing the mental abilities of the different cohorts, it can be observed how their aptitudes are different. A certain generational moment enhances certain skills, and another moment others.
Each historical moment seems to enhance some skills more than others. Thus, to absolutely conclude that young people have greater mental abilities due to the influence of the age variable may be wrong, since we may be comparing what was not enhanced at the time.
Variations in decline according to people
As stated before, there is no one-size-fits- all pattern of decline . In fact, there is a marked interindividual variability, where some skills remain stable and others do not. The decline is therefore different in people, and these differences are attributed to personal, health and psychological variables of the individual.
Not all intelligences decline
Various studies-for example, the two – factor theory of intelligence show how the fluid intelligence or mechanical – marked biológicamente- wanes throughout life, but the crystallized intelligence or pragmatic maintained or even increased.
For all the above, we must be cautious when saying that intelligence when aging is deteriorated compared to the young people of that time, or the skills they had when they were. There are many factors that can be included in these differences, that can be explained and that are far from simplistic discourses where it is wanted to illustrate that the elderly person is less intelligent.
Decline of intelligence vs. Pathological deterioration
When carrying out a neuropsychological evaluation, it must be taken into account that a pathological deterioration, the result of a disease, is not synonymous with loss of intelligence. Intellectual decline is the result of the aging of our brain, and it falls within the normal range. The consequences of pathological deterioration, no.
When intelligence is measured in the tests, you want to see the individual’s ability to adapt to new situations over the years. Although this is measured through standardized tests, it must be taken into account that certain factors may be skewing the results:
- In cohort studies, periodic tests are carried out over years. People and their circumstances change, and therefore they may not be motivated to solve tasks, which can affect their performance.
- There are distant and historical conditions that are very relevant to cognitive development and functioning such as education, nutrition, health status … They cannot be ignored or taken into account when we talk about the general and absolute decline of intelligence as we age, since it is not both age, but those factors that have a greater impact on intelligence.
- The tests may be more or less familiar to subjects of different generations, and some may respond better than others just because of the support —computer, keyboard… -.
The illustrative Wechsler scale
The Wechsler scale – hereinafter WAIS – is the intelligence test par excellence to investigate changes associated with age. It consists of several tests, and has two large scales: the verbal scale and the manipulative one.
The WAIS has allowed us to observe how an increase in intelligence occurs from 17 years to 22. From that age different scoring patterns appear, such as:
- Verbal scores – broadly related to memory and comprehension – grow up to the age of 30. There is a very slight decline until age 67, where it becomes more evident.
- Manipulative scores —perceptual and organizational aspects— clearly decline from age 22, with a very marked change from age 67.
- In general, the total scores experience a clear plateau starting at age 25, and a large decline after age 67.
Conclusions: does intelligence decline with aging?
The conclusions that we can reach from the cohort studies carried out are the following:
- Yes, there is a decline in at least some processes of intellectual functioning with age. Some functions that derive from fluid intelligence decline earlier, as they are strongly conditioned by brain structure and has to do with processing speed. On the contrary, those functions influenced by cultural conditions are deteriorated at very advanced ages or never do so.
- The great differences between the declines in intelligence of a group of people of the same age are modulated by personal and cultural conditions.
- Recent studies have illustrated that there is progress in the intellectual abilities of the most recent older generations with respect to those older older generations —it is relevant to insist that socioeconomic factors play an important role.
However, studies on brain plasticity, learning potential and cognitive reserve are encouraging.
It has been seen, through the assessment of learning potential, that older people have great learning potential, as they can significantly improve their intelligence scores.