Massive psychology study offers an unprecedented look into how personality and intelligence intertwine

A comprehensive new study provides evidence that various personality traits and cognitive abilities are connected. This means that if someone is good at a certain cognitive task, it can give hints about their personality traits, and vice versa.

For example, being skilled in math could indicate having a more open-minded approach to new ideas, but might also be associated with lower levels of politeness. These connections can help us understand why people are different in how they think and act.

The research has been published in the Proceedings of the National Academy of Sciences.

Both personality traits and cognitive abilities are known to predict various important behaviors, outcomes, preferences, and even health-related factors. However, despite their individual significance, the interactions and connections between these two domains have been relatively underexplored.

The researchers aimed to address this gap in knowledge by conducting a large-scale meta-analysis that summarizes the connections between cognitive abilities and personality traits. They wanted to provide a comprehensive understanding of how these domains interact and influence each other, which could have implications for various scientific theories, research studies, and practical interventions.

“Personality traits and cognitive abilities are pillars of individuality,” said study co-author Kevin C. Stanek, who led the Personality and Intelligence Lab at the University of Minnesota-Twin Cities and currently serves as the Global Head of People Analytics at Gilead Sciences.

“Focusing solely on cognitive abilities or personality traits limits research, understanding, and applications. Many research studies, scientific theories, and real-world interventions assume these domains are independent, but they aren’t. Mapping the architecture of personality-intelligence relations unlocks not only scientific insights and practical applications but also reveals deep-rooted patterns in human diversity. By giving scientists, educators, and policymakers a high-resolution map of personality- abilities relations, this study invites us to think more holistically about human potential.”

“More personally, we were interested in probing the intersection of these fundamental domains of psychology to see if we could assemble a panoramic view of their relations across the century, countries, measures, demographics, and millions of people,” Stanek explained. “Not only do these domains help us better understand ourselves, but they also predict important life outcomes from health to divorce, wealth to athletic achievement, work performance to longevity, among many others. Thousands of studies have been conducted on these two domains, but no one has stepped this far back to comprehensively examine their connections.”

To conduct this study, the researchers followed a systematic approach to identify and gather relevant research studies. They performed extensive searches across various databases, including electronic databases, dissertation/thesis catalogs, regional databases, and other sources. They used a wide range of keywords related to both personality traits and cognitive abilities to ensure a comprehensive coverage of the literature.

They applied specific criteria to include studies in their analysis, such as reporting between-person, individual-level, observed, bivariate relations. They excluded studies with certain characteristics, such as studies involving children younger than 12, psychiatric patients, experiments with manipulations that might affect personality or cognitive ability scores, and contrasted/extreme group studies.

In total, they collected data from 1,325 studies, involving over 2 million individuals from diverse demographic backgrounds and various parts of the world. This extensive dataset allowed them to quantitatively analyze the relationships between 79 personality constructs tied to the Big Five personality framework and 97 cognitive abilities.

The Big Five personality framework, also known as the Five-Factor Model (FFM), is a widely recognized and extensively studied psychological model that aims to describe and categorize human personality traits. It organizes personality traits into five broad dimensions or factors that capture the fundamental dimensions of individual differences in personality.

Openness to Experience describes if someone is open to new ideas or prefers familiar things. Conscientiousness describes how organized and responsible someone is. Extraversion describes if someone is outgoing and likes to be around others, or if they prefer alone time. Agreeableness describes how kind and cooperative someone is with others. Finally, neuroticism reflects how much someone experiences negative emotions like worry or sadness.

“This study offers an unprecedented look into how personality and intelligence intertwine,” Stanek told PsyPost. “It presents the most comprehensive examination of the relations between personality traits and cognitive abilities by synthesizing data from thousands of studies and millions of people. We confirmed not just the expected ties, such as the link between openness and intelligence, but also uncovered less obvious links involving neuroticism, extraversion, and conscientiousness.”

Openness-related traits were positively correlated with cognitive abilities. The intellect-related traits (such as curiosity and ideas) were positively correlated with cognitive abilities, particularly verbal and quantitative abilities. The experiencing-related traits (such as fantasy and esthetics) had weaker correlations with cognitive abilities.

“As expected, there are robust, positive relationships between many cognitive abilities and open mindedness (i.e., receptivity to fresh ideas). Curiosity, enjoyment of pondering ideas and thinking more broadly were correlated with a host of cognitive abilities,” Stanek explained.

Extraversion-related traits, reflecting engagement with the external world, showed varying correlations with cognitive abilities. The activity facet of extraversion had positive correlations with cognitive abilities, including general mental ability and processing speed. Other facets of extraversion had more sporadic relationships with cognitive abilities

“There’s a psychological trait called ‘activity,’ which is a facet of extraversion,” Stanek explained. “Active individuals are energetic, enthusiastic, and fast- moving. They enjoy being busy and juggling multiple activities, which often translates into an eagerness to engage with the social world around them. Activity showed strong, positive connections with several cognitive abilities, indicating that individuals who are active and energetic tend to have a better command of various cognitive abilities.”

“Most notably, this includes extensive knowledge, efficient memory retrieval, and enhanced information processing. Regardless of the subject, active folks tend to know more about it. This might be due, at least in part, to their swiftness in processing stimuli and recalling information from long-term memory. The pattern of findings is in stark contrast to the popular stereotype of intellectuals closeted away in their rooms. Instead, the results suggest that high-energy individuals have high mental performance, which allows them to swiftly navigate through complexity with a rich bank of knowledge at their fingertips.”

Agreeableness-related traits, related to getting along with others, had weaker relations with cognitive abilities. However, the aspects of compassion (positive) and politeness (negative) showed distinct patterns. Compassion correlated positively with cognitive abilities, while politeness was negatively correlated.

“One unexpected discovery from our study concerns the two aspects of agreeableness: compassion and politeness,” Stanek said. “Psychologists think of compassion as a willingness to spend energy on helping others, contributing to the wellbeing of a group, which thereby reciprocally creates a personal social safety net. Politeness, on the other hand, is about following social rules for interacting with others. While these may seem like two sides of the same coin, this research reveals they’re connected to cognitive abilities in contrasting ways.”

“It could be that learning social rules is a means of compensating for lower ability to take on the world’s complexity alone. Alternatively, being polite may distract our cognitive resources toward controlling our behavior to avoid being rude or confrontational. Similarly, if too much mental energy is spent on maintaining social graces, it may detract from the ability to accumulate knowledge in other domains.”

Conscientiousness-related traits, involving self-discipline and organization, generally correlated positively with cognitive abilities. Industriousness, dependability, and orderliness had varying relations with different cognitive abilities. Cautiousness was negatively correlated with acquired knowledge abilities.

“The industriousness aspect of conscientiousness and compassion aspect of agreeableness positively correlated with many forms of knowledge,” Stanek said. “That is, the more industrious (read: hardworking) and compassionate people are, the better their verbal (e.g., vocabulary) and quantitative (mathematical) knowledge tend to be. The trend wasn’t limited to just verbal and quantitative knowledge, either – most other acquired knowledge areas examined showed a strong link with these personality traits.”

“What does this mean? Think of it as these traits being personal guides, investing inherent cognitive abilities (e.g., reasoning, memory, visualization) over decades in the acquisition of new knowledge. Essentially, if you’re industrious and compassionate, you’re likely to be better at transforming your raw talents into concrete knowledge and skills. This discovery suggests an exciting connection between personality traits and how we learn.”

Neuroticism-related traits, which involve negative emotions, were generally correlated negatively with cognitive abilities. The correlations were modest at the global neuroticism level but stronger at the aspect and facet levels. For example, depression, uneven temper, suspiciousness, and anxiety had sizable negative correlations with cognitive abilities.

“People who experience high levels of trait depression or anxiety tend to find it harder to accumulate knowledge or reason logically,” Stanek told PsyPost. “Whether it’s piecing together a puzzle through inductive reasoning or deducing conclusions based on known facts, these abilities seem to take a hit when emotions are at the helm.”

“More than that, emotionally unstable individuals may be suspicious of others and quick to react with intense, often negative, feelings. Such emotional turbulence can take a toll on individuals’ ability to regulate psychological processes, including cognitive performance. In other words, emotionally volatile individuals may find it more challenging to concentrate, remember things, or solve problems – key components of cognitive performance.”

These links between personality and cognitive abilities could have common underlying factors like genetics, brain function, culture, education, and more. Understanding these connections can help researchers uncover hidden causes that influence both personality and cognitive abilities.

“Knowing how personality and intelligence are related allows us to ponder the much deeper question of why,” said Deniz Ones, a co-author of the study and a professor of psychology at the University of Minnesota. “These findings revolutionize our understanding of human diversity and individuality. Only by knowing ourselves can we fully tap into our potential.”

Stanek proposed several potential directions for future research.

“Our study offers a treasure trove of data that we hope will inspire new avenues of investigation,” he explained. “Researchers should further explore under-studied connections and expand our dataset to include more dimensions of human psychology, such as personal interests and values.”

“Our study presents a snapshot of the fascinating intersection of personality traits and cognitive abilities,” Stanek added. “But does the picture look the same in all groups of people? Future research should explore whether our findings hold true for specific populations, such as those with mental health conditions, children, or the elderly. We’re also curious to know how these connections might evolve within individuals over time – an exciting challenge for longitudinal studies.”

The new findings are the result of years of work.

“This research was unfunded and therefore would not have been possible without the contributions of thousands of researchers, librarians, translators, and organizations as well as our team of over 30 research assistants who toiled for five years to compile and code the tens of thousands of effect sizes that contributed to this research,” Stanek explained. “We are immensely grateful to work with such talented colleagues on the journey of scientific discovery.”

While it was not the focus of the study, Stanek and his team also observed that the ways in which researchers study personality have remained quite similar for decades.

“It’s surprising that the methods used today are essentially the same as those used 100 years ago to study personality (i.e., mostly people responding to questions about how much a statement describes them) and cognitive ability (i.e., mostly people computing numbers, defining words, and manipulating shapes and patterns),” the researcher told PsyPost. “Innovative methods like sensors, digital exhaust, and generative AI will provide breakthrough perspectives on age-old topics, such as personality and intelligence but multiplying the volume of data, increasing the accuracy, and reducing the effort/cost of acquisition.”

“Beyond the article in Proceedings of the National Academy of Sciences, we also have a website that offers ways to interact with the results as well as a forthcoming book that should be out in the next couple months,” Stanek added.

The study, “Meta-analytic relations between personality and cognitive ability“, was authored by Kevin C. Stanek and Deniz S. Ones.

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