The putamen is deep inside each cerebral hemisphere, one on each side: a rounded mass of grey matter at the base of the forebrain, lying under the insula, outside the globus pallidus and the internal capsule. [1][2]
The 3D brain needs JavaScript. The text below still says where the putamen is and what it does.
Slice
Opens cut by a front (coronal) slice through the putamen. Drag to turn, pinch or scroll to zoom, tap any part to name it; .
Takes part in: movement — see every part of each lit together.
Where it is
A rounded nucleus at the base of the forebrain, above the midbrain; with the caudate nucleus it forms the dorsal striatum, part of the basal ganglia. [1]
With the globus pallidus, just inside it, it forms the lentiform (lens-shaped) nucleus. [1][3]
Going outwards from it: a thin sheet of white matter (the external capsule), the claustrum, a second sheet (the extreme capsule) and then the cortex of the insula. [4]
The internal capsule separates it from the caudate nucleus and thalamus nearer the midline. [5]
What it does
A primary function is to regulate movements at various stages, such as preparation and execution, and to influence various types of learning. It uses the chemical messengers GABA, acetylcholine and enkephalin. [1]
OpenStax describes the basal nuclei (caudate, putamen and globus pallidus) as responsible for cognitive processing, most importantly the processing linked to planning movements. [6]
Connections
Connected to many regions of the cerebral cortex, and to the substantia nigra, the globus pallidus, the claustrum and the thalamus. [1]
Dopamine arrives from the compact part of the substantia nigra; striatal output goes to the globus pallidus and substantia nigra, and from there the basal ganglia loop runs through the thalamus back to the cortex. [7][2]
Inside it
Grey matter. With the caudate nucleus it is called the striatum because of the striped (striated) look of its grey and white matter. [8]
Other names
Putamen is Latin, meaning “nutshell”. With the caudate nucleus it is the dorsal striatum; with the globus pallidus, the lentiform nucleus. [1][3]
Size
On this model the left putamen measures about 43 mm front to back, 26 mm top to bottom and 18 mm side to side (the box it fits in, not its volume); the right one is its mirror image. [9]
Centre of the left putamen compared with the centre of the left globus pallidus: 4 mm further from the midline; 5 mm apart in a straight line. [9]
Centre of the left putamen compared with the centre of the left caudate nucleus: 4 mm further forward, 9 mm further from the midline; 10 mm apart in a straight line. [9]
Facts describe anatomy and normal function only. The 3D model is the adult male BodyParts3D brain (credits and licence); real brains vary in size and shape, so its measurements describe one model, not anyone’s brain.