The State of the art article in this second issue of Dia-logues in Clinical Neuroscience devoted to anxiety providesthe reader with a major review by Dennis S. Charney (page207) about the neurotransmitter and neurohormone sys-tems known to play a role in the different clinical entitieswithin the anxiety disorders (eg, monoamines, corticos-teroids, and sex hormones). He also discusses compoundsthat probably play a role in anxiety, but have not yet beenextensively discussed in this respect (eg, galanin and neu-ropeptide Y). His review describes how these compoundsare involved in various brain systems and during differentchallenges to the individual. Thus, the complete domaincovered by the author includes brain structures and neu-rotransmitters before, during, and after states of stress,pleasure, social exchanges, behavioral conditioning, andresilience.Evolutionary psychology and evolutionary psychiatry canbe defined as the application of Darwinian theories of evo-lution to behaviors of men (or animals). The centralhypothesis is that manyif not allbehaviors have beenselected because of a survival advantage. The Basicresearch review by John S. Price on the evolutionaryaspects of anxiety (page 223) illustrates this hypothesis,and contains a list of strategies that might have been life-saving in ancient times, but that nowadays only representunwanted sequelae of hard-wired behavioral tendenciesto establish safety. In the modern world, where ritualbehaviors play a lesser role than in animal societies andwhere individuals are overloaded with information, thepersistence of all or some of these ancient behavioral ten-dencies might explain some of the clinical symptoms inpsychiatry. The review has been placed in the Basicresearch category not because of the results acquired todate, but because this new approach has generated awealth of research questions that bridge the gap betweensocial behaviors, psychiatric syndromes, and the biology ofthe brain. The therapeutic and beneficial aspects of the pharmaco-logical treatment were reviewed in the first issue on anxi-ety (see Dialogues in Clinical Neuroscience, 2002, Volume4, No. 3). In this, the second issue on anxiety, the Phar-macological aspects article discusses dependence onanxiolytic medications. Lisa L. von Moltke and David J.Greenblatt (page 237) document the statements that benzo-diazepines are efficacious, that they are not widely abused,and that tapering the dose towards treatment interruptioncan be achieved in many patients. The authors underlinethat a history of addiction should lead to the restriction ofbenzodiazepine prescriptions. Finally, since selective sero-tonin reuptake inhibitors (SSRIs) are useful in several anxi-ety disorders, the authors confirm that cases of dependencehave not been reported. They discuss the discontinuationsyndrome, a series of symptoms that follow the abrupt ces-sation of some SSRIs and that can be mistaken for severalother conditions in anxious patients.In the Poster, Thérèse Schunck, Gilles Erb, Christian Gilles,Yann Hode, Izzie J. Namer, Hermann Fuder, and RémyLuthringer give an illustration of the usefulness of functionalmagnetic resonance imaging (fMRI) to explore the biologi-cal changes in models of anxiety induced in normal subjects(page 246). They used the pharmacological model withcholecystokinin-4 (CCK-4) injection and a behavioral modelwhere the subject is anxious during periods of unpre-dictable transcutaneous electrical stimulations. The authorsfound that several paralimbic structures are active duringanticipatory anxiety in both models. Of interest, they findthat the activation of other regions varies according to thephenomenon that the subject anticipates, ie, in the tran-scutaneous electrical stimulation model, brain regions areactivated that are known to be related to the physical andthe psychological aspects of pain perception. The Clinical research article by Luc Staner (page 249)offers a compact review of sleep physiology and anextended analysis of the interactions between anxiety dis-orders and sleep disturbances, showing the high rate ofcomorbidity. The author reminds us that increased arousalis inherent to anxiety states, whether these are justified ornot. He then explains how two components of the stresssystem, the corticotropin-releasing hormone system andthe locus ceruleus noradrenergic system, interact withsleep regulation. The rates of insomnia and hypersomniaincrease in all anxiety disorders, but some changes in sleepare specific to given disorders: nocturnal panics in panicdisorder, possibly shorter rapid-eye movement (REM) laten-cy in obsessive-compulsive disorder, and recurrent night-mares in posttraumatic stress disorder. The treatment of2 0 5I n t h i s i s s u e . . .