06551 - Neurophysiology

Course contents

Cellular physiology

Diffusion and transport across the plasma membrane

Composition of intracellular and extracellular compartments. Homeostasis. Functional features of the plasma membrane. Mechanisms of diffusion and transport across the plasma membrane. Osmosis. Plasma membrane ion channels. Membrane receptors.

Ionic equilibria and membrane potentials

Ion fluxes and ion equilibria. Physico-chemical bases of the resting membrane potential. Role of the sodium-potassium pump. Graded potentials. Pacemaker activity.  Action-potential: origin and propagation in myelinated and unmyelinated axons. 

Synaptic transmission

Chemical and electrical synapses. Presynaptic and postsynaptic mechanisms of chemical transmission. Postsynaptic excitatory and inhibitory potentials. Neurotransmitters: syntesis, release, interaction with membrane receptors, inactivation. 

Sensory receptors 

Mechanisms of signal trasduction. Classification of sensory receptors. Primary sensory coding: type of stimulus, intensity, duration and localization. 

Skeletal muscle cell

Structure of the skeletal muscle cell. Neuromuscular synaptic transmission. Excitation-contraction coupling. Molecular mechanism of contraction. Isotonic and isometric contraction. Graduation of strength in the muscle contraction. Skeletal muscle cell metabolism. Functional characteristics of oxidative and glycolytic skeletal muscle cells. Motor units. Muscular ipotrophy and hypertrophy. Effects of physical training.

Smooth muscle cell

Structure of the smooth muscle cell. Single-unit and multi-unit smooth muscles. Molecular mechanisms and control of contraction. Pacemaker activity and neural, hormonal, mechanical and chemical modulation of single-unit smooth muscles contraction.

 

Anatomo-functional organization of the nervous system

Principal functional elements of the nervous system. Classification of neurons, nerve fibers and glial cells. Functional organization of the central and peripheral nervous system. Blood-brain barrier. Somatic and visceral sensory-motor integration.

 

Sensory systems

General principles of sensory physiology. Functional organization of the sensory systems. Somatosensory (touch, proprioception, interoception, thermoception, pain), visual, auditory, vestibular, gustatory and olfactory systems: adequate stimuli, specific receptors, mechanisms of signal transduction, ascending neural pathways, cortical representation and elaboration. Endogenous mechanisms of pain modulation.

 

Somatic motor nervous system

Functional organization of the somatic motor nervous system. Mechanisms of modulation of muscular strength.

Reflex movements

Reflex arcs. Spinal reflexes: stretch reflex, tendon reflex, flexor reflex, crossed extensor reflex. Central control of reflex responses.

Control of posture and locomotion

Posture control: role of proprioceptors, brainstem nuclei and cerebellum. Locomotion control: role of spinal cord, proprioceptors and brainstem nuclei. Central control of posture and locomotion.

Voluntary movements

Motivation, ideation, planning and execution of voluntary movements. Role of cortical motor areas, cerebellum, basal ganglia, thalamus and braistem nuclei. Somatotopic representation of the skeletal muscles in the primary motor cortex. Functional organization of the descending motor pathways. Motor learning. Peripheral control of voluntary movements, role of neuromuscular spindles.

 

Autonomic nervous system  

Anatomo-functional organization of the autonomic nervous system: orthosympathetic, parasympathetic and enteric sections. Pre- and post-ganglionic neurotransmitters. Nicotinic and muscarinic cholinergic receptors. Alpha and beta adrenergic receptors. Effects of orthosympathetic and parasympathetic stimulation on different organs. Autonomic reflexes.  

 

Higher functions of the nervous system

Association areas of the cerebral cortex. Speech nervous centers. Limbic system. Emotions, mood, vigilance, attention, function of nervous ascending pathways. Electroencephalography, wake-sleep cycle. Learning, memory, synaptic plasticity.

Readings/Bibliography

Suggested booktext: E. Carbone, F. Cicirata, G. Aicardi, Fisiologia: dalle molecole ai sistemi integrati, EdiSES, 2009.

Office hours

See the website of Giorgio Aicardi