chapter 007 nervous system

Chapter 7The nervous system

Copyright © Elsevier Ltd 2005. All rights reserved.

Figure 7.1 Functional components of the nervous system.


Figure 7.2 The structure of neurones. (Arrow indicates direction of impulse conduction.)


Figure 7.3 Nerve fibres: A. Myelinated. B. Non-myelinated.


Figure 7.4 Saltatory conduction of an impulse in a myelinated nerve fibre.


Figure 7.5 Simple propagation of an impulse in a non-myelinated nerve fibre. (Arrows indicate the direction of impulse transmission.)


Figure 7.6 Functional components of the nervous system.


Figure 7.7 Sensory nerve endings in the skin.


Figure 7.8 Diagram of a synapse.


Figure 7.9 Neurotransmitters at synapses in the peripheral nervous system.


Figure 7.10 Motor unit: A. Longitudinal section. B. Cross-section.


Figure 7.11 Blood brain barrier.


Figure 7.12 The meninges covering the brain and spinal cord.


Figure 7.13 The positions of the ventricles of the brain (in yellow) superimposed on its surface. Viewed from the left side.


Figure 7.14 Arrows showing the flow of cerebrospinal fluid.


Figure 7.15 The parts of the central nervous system.


Figure 7.16 The lobes and sulci of the cerebrum.


Figure 7.17 A section of the cerebrum showing some connecting nerve fibres.


Figure 7.18 The cerebrum showing the functional areas.


Figure 7.19 The motor nerve pathways: upper and lower motor neurones.


Figure 7.20 A. The motor homunculus showing how the body is represented in the motor area of the cerebrum. B. The sensory homunculus showing how the body is represented in the sensory area of the cerebrum. (Both A and B are from Penfield W, Rasmussen T 1950 The cerebral cortex of man. Macmillan, New

York. © 1950 Macmillan Publishing Co., renewed 1978 Theodore Rasmussen.)


Figure 7.21 The cerebellum and associated structures.


Figure 7.22 The meninges covering the spinal cord. Each cut away to show the underlying layers.


Figure 7.23 Section of the distal end of the vertebral canal.


Figure 7.24 The spinal cord and spinal nerves.


Figure 7.25 A section of the spinal cord showing nerve roots on one side.


Figure 7.26 One of the sensory nerve pathways from the skin to the cerebrum.


Figure 7.27 A simple reflex arc involving one side only.


Figure 7.28 Transverse section of a peripheral nerve showing the protective coverings.


Figure 7.29 The relationship between sympathetic and mixed spinal nerves. Sympathetic part in green.


Figure 7.30 The meninges covering the spinal cord, spinal nerves and the plexuses they form.


Figure 7.31 The cervical plexus.


Figure 7.32 The brachial plexus.


Figure 7.33 The main nerves of the arm.


Figure 7.34 The distribution and origins of the cutaneous nerves of the arm.


Figure 7.35 The lumbar plexus.


Figure 7.36 Sacral and coccygeal plexuses.


Figure 7.37 The main nerves of the leg.


Figure 7.38 Distribution and origins of the cutaneous nerves of the leg.


Figure 7.39 Segmental distribution of the thoracic cutaneous nerves.


Figure 7.40 The inferior surface of the brain showing the cranial nerves.


Figure 7.41 The cutaneous distribution of the main branches of the right trigeminal nerve.


Figure 7.42 The position of the vagus nerve in the thorax viewed from the right side.


Figure 7.43 The sympathetic outflow, the main structures supplied and the effects of stimulation. Solid red lines preganglionic fibres; broken lines postganglionic fibres. There is a right and left lateral chain of ganglia.


Figure 7.44 The parasympathetic outflow, the main structures supplied and the effects of stimulation. Solid blue lines preganglionic fibres; broken lines postganglionic fibres. Where there are no broken lines, the postganglionic neurone is in the wall of the structure.


Figure 7.45 Referred pain. Pain perceived to originate from the tissues supplied by the damaged nerve. Y stimulates X and pain is perceived in the shoulder.


Figure 7.46 Regrowth of peripheral nerves following injury.


Figure 7.47 Effects of different types of expanding lesions inside the skull: A. Subdural haematoma. B. Subarachnoid haemorrhage. C. Tumour or intracerebral haemorrhage.


Figure 7.48 Types of haemorrhage causing stroke: A. Intracerebral. B. Subarachnoid.


Figure 7.49 Shuffling gait of Parkinson’s disease.


Figure 7.50 Phenylketonuria: A. Phenylalanine present. B. Phenylalanine absent.


Figure 7.51 Prolapsed intervertebral disc. A. Viewed from the side. B. Viewed from above.


Figure 7.52 Spina bifida.
