Nervous system in 3D

Central, peripheral and autonomic parts

Each spinal nerve forms from an anterior (motor) root and a posterior (sensory) root with its spinal ganglion, then divides into anterior and posterior rami. The anterior rami form the cervical, brachial, lumbar and sacral plexuses, which supply the neck and limbs, while in the thorax they continue as the intercostal nerves.

The autonomic nervous system controls the viscera, vessels and glands. Sympathetic outflow arises from the thoracic and upper lumbar spinal cord. Sympathetic preganglionic fibres synapse in paravertebral or prevertebral ganglia; fibres to the adrenal medulla form a special pathway. Its parasympathetic part travels with cranial nerves III, VII, IX and X and the sacral nerves S2–S4.

What the 3D model shows

The nerves view has 423 parts over a faded skeleton: the brain, the spinal cord segments C1–S5 and the cauda equina, the cranial nerves, spinal nerve roots and a spinal ganglion, and the sympathetic trunk with its ganglia. In the upper limb it follows the brachial plexus through its roots, trunks and divisions into the axillary, musculocutaneous, median, ulnar and radial nerves down to the digital branches. The trunk has the intercostal, iliohypogastric, ilio-inguinal and genitofemoral nerves; the lower limb has the femoral, obturator, sciatic, tibial and fibular nerves, the plantar nerves and the pudendal nerve. The second view adds about 500 muscle parts.

How to study the nervous system

In the nerves view, pick one limb nerve and trace it from its spinal cord segments to its last branch: for example, the median nerve from the brachial plexus through the arm and forearm to the fingers. From the posterior view, follow the sciatic nerve down the thigh until it divides into the tibial and common fibular nerves. Then switch to the nerves and muscles view to see which muscles each nerve runs between. Close the model and list the terminal branches of the brachial plexus and the nerves of the lower limb from memory.