In his invited address New Developments in Panic at the AABT convention David Barlow raised an interesting issue. In re-capping what we’ve learned over the past few decades he observed that we’ve learned a lot about the neurobiological basis of both anxiety and panic and about the neurological circuts involved. On the psychological level, anxiety is a future-oriented emotion, based on the anticipation of danger, while panic is present-orientented and it is based on the perception of a current emergency. On the physiological level, anxiety and panic appear to be functionally different emotions which are localized in different areas of the brain.
He noted that in 1980 the term “neurosis” died when DSM was revised and this freed us from a great deal of baggage which went with that concept. For quite a while the trend has been to split diagnoses into smalled, more specific categories and this trend has reached its zenith in DSM-IV. However, in personaility psychology there has been a continuing focus on some sort of general underlying trait which cut across specific categories. Despite our attempts to draw narrow, specific diagnostic criteria, there is a great deal of overlap among diagnostic categories and substantial comorbidity.
Interestingly, if you treat a specific disorder, comorbid disorders often improve substantially even though they weren’t targeted by the treatment. Also, treatment approaches to different disorders have a lot in common. For anxiety disorders, eating disorders, dissociative disorders, etc. The pharmacological treatment of choice tends to be an SSRI and the CBT approaches tend to involve exposure to stimuli which elicit the problem while preventing cognitive and/or behavioral avoidance.
Out in real life, clinicians often encounter clients who present a mixture of anxiety and depression. When you compare anxious and depressed individuals with individuals who have no mental disorder, you find something interesting. In major depression, anxiety is also elevated, just not as much as depression is. In anxiety disorders, depression is also elevated, just not as much as anxiety is. Anxiety and depression do not appear to be independent of each other. As Barlow said, “These disorders overlap much more than they are distinctive”
He suggested that one can think in terms of a general “negative affect disorder” which subsumes more specific subtypes and better encompasses similarities as well as distinctions between both anxiety disorders and mood disorders.
There is growing evidence that some people have a general tendency towards negative thinking, worry, and dysphoric mood (which sounds suspiciously similar to neuroticism) and we’re making considerable headway in understanding what causes it. There appears to be a heritable component, a general tendency to react strongly to events which is not specific to any disorder and which is shaped by early experience. (see the post about "a gene for negative thinking" earlier in the forum)
Early experiences with unpredictability and uncontrollability seem to be particularly important. Monkeys who grow up with more experience of uncontrollability end up demonstrating the monkey equivalents of increased anxiety. Studies of baboons in the wild have led to an understanding of physiological pathway through which the experience of a lack of control and lack of predictability leads to lasting changes in the hyppocampus. This produces physiological changes parallel to the lasting physiological changes seen in studies of individuals with PTSD and Panic Disorder.
In baboons the physiological changes are paralelled by personality changes similar to those seen in anxiety disorder patients. Barlow’s view is that the perception of uncontrolability and unpredictability is more important than the specific traumatic events except in extreme cases (i.e. PTSD).
He also suggests that certain parenting styles seem to contribute. On laboratory tasks, mothers of anxious children tend to be more involved/overinvolved in a way which is tense and cold, pressured, not warm. (Fathers are now being studied as well) He noted that some of these findings parallel Attachment Theory in psychodynamic circles.
The idea is that early experience of uncontrollability and unpredictability leads to a general vulnerability to anxiety and depression. Other early experiences produce more specific vulnerabilities, thus serious illness, a parental emphasis on social evaluation, an emphasis on controlling unacceptable thoughts, etc. would create more specific vulnerabilities. The combination of biological vulnerability, generalized psychological vulnerability, and specific psychological vulnerabilities contribute to the eventual development of specific disorders when appropriate trigger events occur. He reports that on-going research is producing results consistent with this view.
Interestingly, he sees generalized anxiety as a precursor to the development of depression. He and colleagues are working out the details of the way in which these events unfold using the results of brain imaging research.
At this point, he believes the inborn biological contributions to the development of anxiety and depression are smaller than the contribution of early experience and current events.
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