Shafaqna Health: A new genetic analysis suggests that the relationship between psychiatric disorders and intelligence is more complex than previously thought, with genetic risk for conditions such as schizophrenia and bipolar disorder showing different associations with problem-solving, processing speed and accumulated knowledge, according to PsyPost.
Researchers analyzed genetic data from hundreds of thousands of people, including roughly 439,000 participants in the analysis of crystallized knowledge. Rather than treating intelligence as a single trait, they examined three distinct cognitive domains: processing speed, fluid reasoning and crystallized knowledge—the facts and vocabulary acquired through education and life experience.
The study identified 78 genetic regions associated with crystallized knowledge, including eight that had not previously been linked to cognitive traits. Genetic factors associated with fluid reasoning were more active in the brain during early childhood, while those linked to crystallized knowledge showed greater activity during adolescence and early adulthood.
When these cognitive profiles were compared with genetic risk for five psychiatric conditions, the associations varied substantially. Schizophrenia and bipolar disorder showed similar patterns: higher genetic risk was associated with slower reaction times and lower fluid reasoning, but with higher crystallized knowledge and stronger non-cognitive traits related to educational attainment.
Other disorders showed different patterns. Genetic risk for ADHD was associated with slightly faster reaction times but lower fluid reasoning, crystallized knowledge and educational-related skills. Autism spectrum disorder showed a positive association only with crystallized knowledge, while Alzheimer’s disease was associated only with lower fluid reasoning.
The researchers also found a strong genetic relationship between openness to experience and crystallized knowledge, suggesting that curiosity and a tendency to seek intellectually stimulating experiences may contribute to the accumulation of knowledge over time.
The authors stress that these findings concern genetic correlations, not direct causes. Genetic liability for a psychiatric disorder does not mean that an individual will develop the disorder, nor does the association imply that people diagnosed with conditions such as schizophrenia or autism necessarily have higher cognitive abilities.
The study, published in Nature Communications, was based primarily on participants of European ancestry, meaning the findings may not generalize to other populations. Researchers say future work could examine whether some genetic variants linked to psychiatric risk also provided cognitive or behavioral advantages during human evolution.
Source: PsyPost
