All parts of the brain › Functions › Intelligence

What part of the brain controls intelligence?

No single part: the best-known model, Jung and Haier’s parieto-frontal integration theory (P-FIT), ties intelligence to a network centred on the dorsolateral prefrontal cortex and the inferior and superior parietal lobules. [1][2]

Honest limit: P-FIT is one model, built from imaging studies of groups; intelligence is not located in one place, and this page says nothing about any person. [1][2]

The occipital lobe, the fusiform gyrus, the superior temporal gyrus, the angular gyrus, the supramarginal gyrus, the superior parietal lobule, the middle frontal gyrus, the inferior frontal gyrus and the cingulate gyrus lit in red on a 3D model of the brain, seen from the front left and above

Loading the 3D brain…

Not lit: the frontal pole (not a shape in this model). Lit: whole parts; region borders not drawn.

Slice

All 9 parts are lit together. Drag to turn, pinch or scroll to zoom, tap a part on the brain or a name in the list to focus it; .

In it, temporal and occipital areas first take in what is seen and heard, the parietal cortex abstracts it, the frontal lobe tests ideas about it with the parietal cortex, and the anterior cingulate picks the answer and holds back the rest. [1][2]

Not lit: The frontal pole (Brodmann area 10), also named by the model, is not a separate shape in this 3D model, so it has no marker of its own. [2]

The dorsolateral prefrontal cortex, the anterior cingulate cortex and Wernicke’s area are regions on these gyri, not separate shapes. The 3D model draws only whole gyri, so the gyrus that holds each area is lit; the area’s exact border is not drawn.

Intelligence: 9 parts lit

Occipital lobe, fusiform gyrus, superior temporal gyrus, angular gyrus, supramarginal gyrus, superior parietal lobule, middle frontal gyrus, inferior frontal gyrus and cingulate gyrus. Tap one to see where it is and what it does.

The parts and their roles

Stage 1, seeing: its extrastriate cortex (Brodmann areas 18 and 19), the visual areas around the primary visual cortex, takes in and recognises what is seen. Area 19 was active during reasoning tasks in more than 40% of the imaging studies the model was built from. [2][1] Where is the occipital lobe?
Stage 1, seeing: the fusiform gyrus (Brodmann area 37), on the underside of the temporal and occipital lobes, is named for recognising, imagining and elaborating what is seen. [2][3] Where is the fusiform gyrus?
Stage 1, hearing: Wernicke’s area (Brodmann area 22) at its back end is named for working out the syntax of what is heard. [2][4] Where is the superior temporal gyrus?
Stage 2: Brodmann area 39, one half of the inferior parietal lobule, where the parietal cortex integrates what the senses delivered and abstracts it. [2][5] Where is the angular gyrus?
Stage 2: Brodmann area 40, the other half of the inferior parietal lobule; it was active in more than 60% of the reasoning studies the model reviewed. [2][1] Where is the supramarginal gyrus?
Stage 2: Brodmann area 7, the model’s most consistent region, active in more than 70% of the reasoning studies it reviewed. [2][1] Where is the superior parietal lobule?
Stage 3: holds the dorsolateral prefrontal cortex (Brodmann areas 9 and 46), which works with the parietal cortex to test ideas about a problem and judge the answers; area 6 at its back end is named too. [2][6][7] Where is the middle frontal gyrus?
Stage 3: Brodmann areas 45 (the pars triangularis) and 47 (the pars orbitalis), the model’s other named frontal areas besides 6, 9, 10 and 46. [2][8] Where is the inferior frontal gyrus?
Stage 4: the anterior cingulate (Brodmann area 32) on its front part selects the response and inhibits the competing ones once a best answer is found. [2][1] Where is the cingulate gyrus?

Named areas on the lit gyri

Dorsolateral prefrontal cortex, on the : On the middle frontal gyrus (Brodmann areas 9 and 46); the model’s main frontal region, where the parietal cortex’s summary is turned into hypotheses and tested. [2][1]
Anterior cingulate cortex, on the : On the front of the cingulate gyrus (Brodmann area 32); the model’s last stage, choosing a response and inhibiting the others. [2]
Wernicke’s area, on the : At the back of the superior temporal gyrus (Brodmann area 22); the model’s entry point for heard language. [2]

How they work together

Where the model comes from: Jung and Haier (2007) reviewed 37 structural and functional imaging studies with 1,557 participants in total, published between 1988 and 2007, and kept the regions that kept turning up when test scores were set against brain scans. Many more regions turned up in single studies; the synthesis keeps fewer. [1][2]
Four stages, one loop: sensory areas in the occipital and temporal lobes, abstraction in the parietal cortex, hypothesis testing between the parietal and frontal lobes, and response selection in the anterior cingulate. The model treats the link between them as part of the answer: white matter, especially the arcuate fasciculus, is thought to carry the traffic reliably. [2]
Efficiency, not size alone: later work tied higher scores to more efficient communication between the dorsolateral prefrontal cortex, the parietal lobe and the anterior cingulate. [1]
Honest limit: not all these areas are equally necessary in every individual, and the theory’s own literature stresses that people may reach the same answer with different cognitive and neural strategies. Structural and lesion studies show which regions matter but do little to show how the work unfolds moment to moment, and there is little published criticism of the model yet, so it is a summary of evidence, not a settled map. [2][1]

Working memory, keeping a few items in mind while you use them, leans on the same dorsolateral prefrontal and parietal cortex and has its own page. [9] What part of the brain controls working memory?

The central executive network, the frontoparietal network that holds and works on information in mind, overlaps the model’s frontal and parietal core: the dorsolateral prefrontal cortex and the parietal cortex around the intraparietal sulcus. [10] Where is the central executive network?

Sources

Facts describe anatomy and normal function only. A part lit here takes part in intelligence; it does not do it alone, and it does other jobs too. The 3D model is the adult male BodyParts3D brain (credits and licence); on it the brainstem includes the midbrain, pons and medulla, so lighting the brainstem lights all three.