Vol 5 n° 3 - Anxiety II
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nside the animal’s form sits the brain, its work broadly to increase the animal’s grip on the world about it, and hardly less the grip of the external world upon the animal. Sherrington, Rede Lecture, 1933 Modern times are not like the times in which our ances- tors evolved.The environment of evolutionary adaptation (EEA) usually refers to the habitat of our immediate ancestors who are thought to have been hunter-gatherers living in bands of about 50 adults, but is really an abstrac- tion which covers all environmental influences going back over three hundred million years to the common ancestor of  humans  and  present-day  reptiles. The  “mismatch” between now and the EEA is thought to be one cause of psychopathology. “Bad news” is a source of anxiety. We now have daily, or even hourly, access to the bad news of six billion people, more than could be generated by a hunter-gatherer band. Moreover, in the EEA, bad news was probably discussed and so shared with other group members, whereas modern man tends to watch it or listen to it on his own, or at least without comment.Therefore, as a practicing clinician, I advise all my anxious patients to avoid watching TV news, and I find that many of them have learned the lesson for themselves.They realize that each item of bad news raises their background level of anxiety, and, of course, severely depressed patients may believe that they are personally responsible for the dis- asters that occur daily around the globe. No one, to my knowledge, has done a controlled trial of “news avoid- ance” as an item of therapy. Much has been written about the evolution of anxiety and its disorders.1-10 Here, rather than repeating familiar arguments, I have tried to break some new ground, look- ing at approaches that may be relevant to research and treatment. I will concentrate on social aspects of anxiety, because  nonsocial  anxieties  have  been  well  covered, whereas there is still something to say about social anxi- ety, particularly the relation of social anxiety disorder to B a s i c   r e s e a r c h 2 2 3 Evolutionary aspects of anxiety disorders John S. Price, DM I Keywords: agoraphobia; anxiety disorder; behavioral ecology; de-escalating strategy; depressive disorder; evolution; triune brain; Yerkes-Dodson law Author affiliations: Department of Psychiatry, South Downs Health NHS Trust, Brighton General Hospital, Brighton, UK Address for correspondence: John S. Price, DM, Odintune Place, Plumpton, BN7 3AN, UK
(e-mail: johnscottprice@hotmail.com) Danger and harm are avoided by strategic decisions made at all three levels of the triune forebrain: rational (neo- mammalian), emotional (paleomammalian), and instinc- tive (reptilian). This applies also to potential harm from conspecifics, which leads to a choice between escalating and de-escalating strategies. Anxiety is a component of de-escalating  strategies  mediated  by  the  paleomam- malian  and  reptilian  forebrains.  When  the  neomam- malian (rational) brain fails to deal with the threat of con- specific  danger,  these  more  primitive  de-escalating strategies may be activated and may present as anxiety disorders. The capacity for concealment of anxiety and other forms of negative affect has also evolved, and exces- sive concealment may lead to psychopathology by break- ing the negative feedback loop of excessive motivation, leading to impaired performance, leading to signals of distress, and  leading to reduced exhortation to succeed on the part of parents and teachers; this situation is illus- trated by a model based on the Yerkes-Dodson law. © 2003, LLS SAS Dialogues Clin Neurosci. 2003;5:223-236. Copyright © 2003 LLS SAS.  All rights reserved www.dialogues-cns.org