THE NERVOUS SYSTEM - PART 2.....continued

The Human Spinal Cord: The study of development, general and microscopic structure of the spinal cord forms the basis on which the function of the grey and the white matter can be worked out by analysing reflexes and diseases of man - The human nervous system. Central, peripheral, and autonomic nervous system - Embryonic development of the spinal cord in frog and human - A. External structure of the spinal cord - Human vertebra. Superior view, left, lateral view of three vertebrae with intervertebral discs, right. - Human central nervous system, lateral view. Position of the dura sac in the spinal canal - Human spinal cord in the spinal canal, lateral view. Opened dural sac, surface view with segments. - Human spinal cord and medulla oblongata. Lateral and dorsal view with spinal nerves, ventral view without nerves. - The membranes of the brain and the spinal cord, diagram - Position of the spinal cord in the spinal canal, t.s. - B. Internal structure of the spinal cord - Spinal cord of cow, t.s. - The grey matter, motor neuron, dendrites, axon - The white matter, myelinated axons - Evolution of the spinal cord. Branchiostoma, lamprey, bony fish - Proportion of grey to white matter. A series of t.s. of human spinal cord - Entrance of dorsal root of spinal nerve into the dorsal column - Spinal ganglion, l.s. - Portion of the spinal cord with roots, ganglia, and spinal nerves, three-dimensional diagram - C. Function of the spinal cord - Simple reflex arc, diagram. Tactile corpuscle - spinal cord - motor end plate on muscle fibre - Knee jerk reflex. Stimulated organ responds - Stepping on a nail. Not stimulated organ responds - Somatic dermatoms supplied by segments of the spinal cord - Polio: syndrome of the ventral grey matter - Tabes, tertiary syphilis: syndrome of the dorsal white matter - Sclerosis of the pyramidal tracts - Hemisection of the spinal cord - Where do the tracts of somatic sensibility cross? - Complete section of the spinal cord - Course of typical sensory tracts: conscious and unconscious deep pressure sensibility, conscious dermal sensibility - Course of typical motor tracts: volitional and involuntary control of movement

The Human Brain - An Introduction to the Reception, Conduction and Transmission of Information: Starting from the external structure, the embryonic development of the brain is treated and its hierarchic structure. As the brain is a connecting and conducting organ, reception, conduction, and transmission of information is treated in a separate chapter. As controlling organ of our body, the brain is its biggest consumer of energy. To introduce into the structure and function of the brain parts, similar to series „The Human Spinal Cord", we shall start from lesions of the medulla oblongata and then follow the course of the typical sensory and motor tracts introduced in the last chapter through the medulla oblongata, pons, mid- and interbrain, to the cortex and cerebellum. A. External structure of the brain - The human brain, lateral view - Sagittal section of the human brain, view on the right half - Frontal section of human brain - Visual and hidden part of the cerebral surface - B. Development of the brain - Hierarchic structure of the human brain, embryonic development - The hierarchic structure of the brain, archipallium and neopallium, sagittal section - C. Reception, conduction, and transmission of information - Electrotonic or resting and action potential - Receptors receive various types of sensory input and transduce them into action potentials of equal magnitude - Intensity of stimulus is reported by impulse frequency - Propagation of action potential along unmyelinated axon - The myelin sheath of peripheral nerve fibres (Schwann cells) - Fine structure of a Ranvier’s node - Composition of myelin compared with liver cell membrane - The myelin sheath in the brain, after Krstic - Fine structure of the myelin sheath - Nerve cell body from the cerebrum with dendrites, axon, and synapses. Diagram - Exciting and inhibiting synapses, location and structure - Synapsis, spatial picture - Synaptic transmission, diagram - D. Blood supply of the brain - The blood supply of the brain, ventral view - The blood supply of the brain, lateral view - Meninges and glia, spatial diagram (after Krstic) - The blood-brain-barrier - The drainage of the brain - The reflections of the dura mater - The ventricles (liquor spaces) of the brain - E. Structure and function of the brain parts - 1. The brain stem - Brain stem, ventral and dorsal view - a. Medulla oblongata - Lesion caused by diving accident - Lesion caused by haemorrhage (stroke) - The course of sensory tracts through the medulla - The course of motor tracts through the medulla - b. Pons - The course of sensory tracts through the pons - The course of motor tracts through the pons. - c. Midbrain and interbrain - The course of sensory tracts through the mid- and interbrain - The course of motor tracts through the mid- and interbrain - 2. Cerebrum - Pyramidal cells of the cerebral cortex - Areas and tracts of the cerebrum, diagram - The lobes and areas of the left cerebral hemisphere - Sensomotor homunculus - Severed corpus callosum: differing functions in cerebral hemispheres - 3. Cerebellum - Views of the cerebellum from various sides - Purkinje cells of cerebellar cortex - Fine structure of the cerebellar cortex, neuronal connections - The most important neuronal arcs of the cerebellar cortex - Tracts connecting the cerebrum with the cerebellum

The Autonomic Nervous System: Starting from the simple pupillary reflex and from emptying the urinary bladder by reflex action, this series introduces into the autonomic nervous system. It widens the knowledge about the antagonistic effect of the sympathetic and parasympathetic part of the autonomic nervous system (ANS). The structural and physiological differences between the somatic and autonomic nervous system are studied as well as the connections between the sympathetic ganglia and the central nervous system. The reflex arcs linking both systems to each other and regulating the body temperature. - Effect of atropine on one eye, eyes exposed to equal incidence of light - Innervation of the iris muscles. Antagonism of sympathetic and parasympathetic nervous system - Control of urinary bladder. Innervation by somatic and autonomic nervous system. - Antagonistic effect of the sympathetic and parasympathetic system on glands and involuntary muscles - Tracts of somatic and autonomic nervous system - Transmitter and inhibiting substances of synapses and motor end plates in the somatic, sympathetic, and parasympathetic system. - The location of the spinal cord, spinal nerves, sympathetic trunk, and ganglion II - Courses of sensory and motor tracts of the autonomic nervous system through the spinal cord, sympathetic trunk, and ganglion II - Regulation of the body temperature. Location of the receptors and controlling centres in the body, negative feedback system.