Letters to the Editor
Re: Listening to the Past: History, Psychiatry, and Anxiety
Dear Editor: Andrea Tone explores the history of psychiatry and the rise of biological psychiatry and suggests ways in which the study of history can shed light on current psychiatric practice (1). Focusing on anxiolytics as a case study in the development of psychopharmacology, she shows how social and political factors converged to popularize, and later stigmatize, outpatient
treatments for anxiety. However, the development and understanding of anxiety disorders, especially panic disorder, have been far from only a psychopharmacological evolution.
Psychopharmacology for panic disorder became especially developed during the 20th-century. The evolution of psychopharmacology in relation to panic disorder can be divided into 3 main moments: first, Klein’s observation of the effectiveness of the tricyclic antidepressants (2); second, the perception of the effectiveness of the benzodiazepines; and finally, the noted effectiveness of the selective serotonin reuptake inhibitors (3).
The biological perspective also entails putting anxiety in the frame of the evolutionist paradigm. Charles Darwin, in The Expression of Emotion in Man and in Animals (4), pointed the way to the search for the adaptive value of the behavioural and psychological processes. Anxiety and fear have their roots in the defensive
reactions of animals observed in response to dangers normally found in the environment. The interpretation of a stimulus or a
situation as dangerous depends on cognitive operations. In humans, cognitive factors acquire importance because of the
intervention of socially codified verbal or nonverbal symbols. Behavioural responses to fear are accompanied by intense
physiological alterations—physical symptoms—and alterations in the emotional state. The physiological alterations comprise
objective measures of anxiety. Thus cardiac frequency, arterial pressure, respiratory frequency, and increased electrical
conductivity of the skin brought on by sweating are the measures most frequently used to determine the degree of anxiety.
The 21st-century will probably be marked by the development of genetic and neuroimaging data about panic and other anxiety
disorders. Panic attacks seem to originate from a network of fear with altered sensibility. This network includes the prefrontal cortex, insula, thalamus, tonsils, and tonsil projections toward the brain stem and hypothalamus (5). Recent research on physiological consequences during a panic attack has shown remarkable findings in regional brain activity in different neuroimaging studies (5). The studies have shown significant increases in cerebral blood flow in panic disorder in several subcortical structures, including the thalamus, hypothalamus, and periaqueductal gray region, in addition to the somatosensory and associative cortices, and the cingulate. Advances in the neuroimaging techniques and technologies available to study key areas involved in panic attacks, and the ability to induce laboratorial panic attacks, thus further detailing brain function during a panic attack, will greatly increase our understanding of the exact neuroanatomical substrates for panic and phobic avoidance. It will also further our understanding of the sites of action of effective therapies.
The mysteries of panic disorder are being revealed through basic and clinical research. Patients suffering from this frightening disorder can be sure that correct diagnosis and adequate treatment are already part of everyday clinical practices. The combination of neuroimaging techniques, laboratorial induction of panic attacks, and psychopharmacological or psychotherapeutic trials could allow a greater understanding of panic disorder—perhaps even new insights into the neuroanatomy and neurophysiology of anxiety disorders.
References
1. Tone A. Listening to the past: history, psychiatry, and anxiety. Can J Psychiatry 2005;50:373–80.
2. Klein DF. Delineation of two drug-responsive anxiety syndromes. Psychopharmacologia 1964;5:397–408.
3. Boyer W. Serotonin uptake inhibitors are superior to imipramine and alprazolam in alleviating panic attacks: a meta-analysis. Int Clin Psychopharmacol 1995;10:45–9.
4. Darwin C. The expression of emotion in man and in animals [1872]. London (UK): Fontana Press; 1999. p 278–309.
5. Gorman JM, Kent JM, Sullivan GM, Coplan JD. Neuroanatomical hypothesis of panic disorder, revised. Am J Psychiatry 2000;157:493–505.
Antonio E Nardi, MD,
Rio de Janeiro, Brazil
|
