A network of topographic numerosity maps in human association cortex.

TY - JOUR

T1 - A network of topographic numerosity maps in human association cortex.

AU - Harvey, Ben M.

AU - Dumoulin, Serge O.

PY - 2017

Y1 - 2017

N2 - Sensory and motor cortices each contain multiple topographicmaps with the structure of sensory organs (such as the retinaor cochlea) mapped onto the cortical surface. These sensorymaps are hierarchically organized. For example, visual fieldmaps contain neurons that represent increasingly large parts ofvisual space with increasingly complex responses1. Some visualneurons respond to stimuli with a particular numerosity —the number of objects in a set. We recently discovered a parietaltopographic numerosity map in which neural numerosity preferencesprogress gradually across the cortical surface2, analogousto sensory maps. Following this analogy, we hypothesizedthat there may be multiple numerosity maps. Numerosityperception is implicated in many cognitive functions, includingforaging3, multiple object tracking4, dividing attention5,decision-making6 and mathematics7–9. Here we use ultra-highfield(7 Tesla, 7T) functional magnetic resonance imaging(fMRI) and neural-model-based analyses to reveal numerosityselectiveneural populations organized into six widely separatedtopographic maps in each hemisphere. Although wedescribe subtle differences between these maps, their propertiesare very similar, unlike in sensory map hierarchies. Thesemaps are found in areas implicated in object recognition, motionperception, attention control, decision-making and mathematics.Multiple numerosity maps may allow interactionswith these cognitive systems, suggesting a broad role forquantity processing in supporting many perceptual and cognitive functions.

AB - Sensory and motor cortices each contain multiple topographicmaps with the structure of sensory organs (such as the retinaor cochlea) mapped onto the cortical surface. These sensorymaps are hierarchically organized. For example, visual fieldmaps contain neurons that represent increasingly large parts ofvisual space with increasingly complex responses1. Some visualneurons respond to stimuli with a particular numerosity —the number of objects in a set. We recently discovered a parietaltopographic numerosity map in which neural numerosity preferencesprogress gradually across the cortical surface2, analogousto sensory maps. Following this analogy, we hypothesizedthat there may be multiple numerosity maps. Numerosityperception is implicated in many cognitive functions, includingforaging3, multiple object tracking4, dividing attention5,decision-making6 and mathematics7–9. Here we use ultra-highfield(7 Tesla, 7T) functional magnetic resonance imaging(fMRI) and neural-model-based analyses to reveal numerosityselectiveneural populations organized into six widely separatedtopographic maps in each hemisphere. Although wedescribe subtle differences between these maps, their propertiesare very similar, unlike in sensory map hierarchies. Thesemaps are found in areas implicated in object recognition, motionperception, attention control, decision-making and mathematics.Multiple numerosity maps may allow interactionswith these cognitive systems, suggesting a broad role forquantity processing in supporting many perceptual and cognitive functions.

U2 - 10.1038/s41562-016-0036

DO - 10.1038/s41562-016-0036

M3 - Article

SN - 2397-3374

VL - 1

JO - Nature Human Behaviour

JF - Nature Human Behaviour

M1 - 36

ER -