1 Neurosteroids: From Definition and Biochemistry to Physiopathologic Function -- 2 Molecular Biology and Developmental Regulation of the Enzymes Involved in the Biosynthesis and Metabolism of Neurosteroids -- 3 Cytochrome P450 in the Central Nervous System -- 4 Steroidogenic Factor 1 Plays Key Roles in Adrenal and Gonadal Development and in Endocrine Function -- 5 Peripheral-Type Benzodiazepine Receptor: Role in the Regulation of Steroid and Neurosteroid Biosynthesis -- 6 Aspects of Hormonal Steroid Metabolism in the Nervous System -- 7 The Selective Interaction of Neurosteroids with the GABAA Receptor -- 8 Potentiation of GABAergic Neurotransmission by Steroids -- 9 Neurosteroid Antagonists of the GABAA Receptors -- 10 Modulation of Ionotropic Glutamate Receptors by Neuroactive Steroids -- 11 Steroidal Modulation of Sigma Receptor Function -- 12 Steroid Modulation of the Nicotinic Acetylcholine Receptor -- 13 Neuroactive Steroid Modulation of Neuronal Voltage-Gated Calcium Channels -- 14 Gonadal Hormone Regulation of Synaptic Plasticity in the Brain: What Is the Mechanism? -- 15 Steroid Effects on Brain Plasticity: Role of Glial Cells and Trophic Factors -- 16 Steroid Receptors in Brain Cell Membranes -- 17 Novel Mechanisms of Estrogen Action in the Developing Brain: Role of Steroid/Neurotrophin Interactions -- 18 Neurosteroids: Behavioral Studies -- 19 Remarkable Memory-Enhancing Effects of Pregnenolone Sulfate with Pheromone-Like Sensitivity: An Amplificatory Hypothesis -- 20 The Neuropsychopharmacological Potential of Neurosteroids