The heritability of intelligence sits at roughly 70–80% in adulthood, but genome-wide association studies aggregating thousands of common variants currently account for only about 10–15% of variance in cognitive ability. The gap — the so-called “missing heritability” — is one of the most discussed problems in modern intelligence research. Epigenetics …
Spatial reasoning and abstract reasoning are routinely treated as two distinct cognitive abilities in lay accounts and in some applied testing contexts. The first is associated with rotating mental images, navigating environments, and visualising three-dimensional structure; the second with detecting patterns, reasoning about analogies, and manipulating symbols disconnected from physical …
That people with more education score higher on IQ tests is one of the oldest findings in psychology. The harder question is whether schooling causes the higher scores, or whether smarter children simply stay in school longer. Untangling the two requires research designs that go beyond ordinary correlation — and …
