Brain Activity Patterns in Anxiety-Prone People Suggest Deficits in Handling Fear

Anxiety as a personality trait appears to be linked to the functioning of two key brain regions involved in fear and its suppression, according to an NIMH-funded study. Differences in how these two regions function and interact may help explain the wide range of symptoms seen in people who have anxiety disorders. The study was published February 10, 2011 in the journal, Neuron.

Background

Anxiety disorders are characterized by an excessive, irrational dread of everyday situations. Some people may experience general, chronic anxiety, while others become anxious in response to one or more specific triggers. Many studies have implicated two brain regions in anxiety—the amygdala in fear responses and the ventral prefrontal cortex (vPFC) in suppressing or regulating fear. Questions remain, however, about how trait anxiety—a person’s typical anxiety level on any given day—affects amygdala and vPFC functioning.

To explore these questions, Sonia Bishop, Ph.D., of the University of California Berkeley (at the University of Cambridge (UK) at the time of data collection), and colleagues designed a series of experiments to determine how the amygdala and vPFC responded in three types of situations:

• Cued fear—a neutral signal or cue is followed by an aversive event. In this study, the cue was an actor in a video placing his hands over his ears and the aversive event was a loud scream. The cue provided a reliable prediction of the aversive event. Cued fear can be compared to the situation-specific type of anxiety experienced by those with a specific phobia, such as a fear of heights.
• Contextual fear—a neutral cue and an aversive event occur independently of each other. The cue did not provide a reliable prediction of the aversive event. Contextual fear may be similar to the non-specific anxiety that affects people with generalized anxiety disorder.
• Safety—a neutral signal or cue occurs alone without an aversive event. The safety situation served as a comparison for the other two situations.

The researchers assessed the level of trait anxiety of 23 healthy study participants, ages 18 to 41. Each participant underwent a training session that exposed them to the above conditions. Two days after the training session, participants had their brain activity recorded through functional magenetic resonance imaging (fMRI), a noninvasive imaging method, while re-exposed to the cued fear, contextual fear, and safety conditions in the scanner.
Results from the Study

Participants with high trait anxiety showed greater amygdala response to cued fear situations compared to those with low trait anxiety. According to the researchers, this finding suggests that individual differences in amygdala response may contribute to differences in vulnerability to cue-specific anxiety disorders, such as specific phobia.

Participants with low trait anxiety showed increased vPFC activity in response to cued fear and more strongly sustained vPFC activity during contextual fear situations, compared to those with high trait anxiety. Notably, vPFC activity in participants with low trait anxiety occurred before the aversive event had ceased. The researchers suggest that this process—engaging brain areas that help to suppress fear even when the source of fear is still present—may help to protect against chronic anxiety disorders even when stressful life events are ongoing.
Significance

The study’s findings support a potential role of the amygdala in vulnerability to anxiety disorders and a potential role of the vPFC in protection against them.

“Individual differences in the functioning of one or both of these brain regions may help account for the variability in symptoms across different anxiety disorders,” said Bishop. “A better understanding of these processes may help inform treatment choice and predict treatment response.”

This study was supported in part by a Biobehavioral Research Award for Innovative New Scientists (BRAINS) from NIMH. Dr. Bishop was one of 12 researchers to receive this award in 2010.

Reference

Indovina I, Robbins TW, Núñez-Elizalde AO, Dunn BD, Bishop SJ. Fear-Conditioning Mechanisms Associated with Trait Vulnerability to Anxiety in Humans. Neuron. 2011 Feb 10;69(3):563-71.

Source: National Institute of Mental Health

Majority of United States Adolescents with Severe Mental Disorders Have Never Received Treatment for Their Conditions

A recent study by Merikangas and colleagues published in the January 2011 issue of the Journal of the American Academy of Child and Adolescent Psychiatry (JAACAP) shows that only half of adolescents that are affected with severely impairing mental disorders ever receive treatment for these conditions.

The researchers found that approximately one third of adolescents with any mental disorder received services for their illness (36.2%). Disorder severity was significantly associated with an increased likelihood of receiving treatment, yet only half of adolescents who were identified as having severely impairing mental disorders had ever received mental health treatment for their symptoms.

In the article titled “Service Utilization for Lifetime Mental Disorders in U.S. Adolescents: Results of the National Comorbidity Survey–Adolescent Supplement (NCS-A),” Dr. Merikangas and colleagues examined the rates of treatment for specific mental disorders in the NCS-A. The NCSA is a nationally representative, face-to-face survey of 10,123 adolescents aged 13 to 18 years in the continental United States.

The authors examined rates of treatment for DSM-IV disorders, and correlated the severity, number of disorders, and comorbidity in a nationally representative sample of 6,483 adolescents 13 to 18 years old for whom information on service use was available from an adolescent and a parent report. Sociodemographic correlates were also evaluated.

Treatment rates were highest in those with attention-deficit/hyperactivity disorder (ADHD) (59.8%) and behavior disorders, such as oppositional defiant disorder (ODD) and conduct disorder (CD) (combined 45.4%). The picture is more discouraging for those adolescents with anxiety, eating, or substance use disorders for whom less than 20% received treatment.

Furthermore, the investigators found that Hispanic and non-Hispanic Black adolescents were less likely than their White counterparts to receive services for mood and anxiety disorders, even when such disorders were associated with severe impairment. In the article, Merikangas and colleagues comment, “marked racial disparities in lifetime rates of mental health treatment highlight the urgent need to identify and combat barriers to the recognition and treatment of these conditions.”

Read the full press release on JAACAP.

Breathing therapy reduces panic and anxiety

ANI has a small article on Sify about some new research demonstrating the effectiveness of breathing therapy in reducing symptoms of panic and anxiety attacks.  The premise behind the approach is that normalizing breathing can reduce symptoms.

I’m delighted to see this research as normalizing breathing is an approach I’ve been incorporating in my clinical work for decades since I came to the conclusion that one thing all effective therapies for stress-related conditions seemed to have in common was that they altered breathing patterns towards more relaxed/normalized breathing.

Here’s the abstract from the new research study:

Respiratory and cognitive mediators of treatment change in panic disorder: Evidence for intervention specificity.
Meuret, Alicia E.; Rosenfield, David; Seidel, Anke; Bhaskara, Lavanya; Hofmann, Stefan G.
Journal of Consulting and Clinical Psychology, Vol 78(5), Oct 2010, 691-704.

Abstract

Objective: There are numerous theories of panic disorder, each proposing a unique pathway of change leading to treatment success. However, little is known about whether improvements in proposed mediators are indeed associated with treatment outcomes and whether these mediators are specific to particular treatment modalities. Our purpose in this study was to analyze pathways of change in theoretically distinct interventions using longitudinal, moderated mediation analyses.

Method:  Forty-one patients with panic disorder and agoraphobia were randomly assigned to receive 4 weeks of training aimed at altering either respiration (capnometry-assisted respiratory training) or panic-related cognitions (cognitive training). Changes in respiration (PCO₂, respiration rate), symptom appraisal, and a modality-nonspecific mediator (perceived control) were considered as possible mediators.

Results: The reductions in panic symptom severity and panic-related cognitions and the improvements in perceived control were significant and comparable in both treatment groups. Capnometry-assisted respiratory training, but not cognitive training, led to corrections from initially hypocapnic to normocapnic levels. Moderated mediation and temporal analyses suggested that in capnometry-assisted respiratory training, PCO₂ unidirectionally mediated and preceded changes in symptom appraisal and perceived control and was unidirectionally associated with changes in panic symptom severity. In cognitive training, reductions in symptom appraisal were bidirectionally associated with perceived control and panic symptom severity. In addition, perceived control was bidirectionally related to panic symptom severity in both treatment conditions.

Conclusion: The findings suggest that reductions in panic symptom severity can be achieved through different pathways, consistent with the underlying models.

To translate the above into a more reader-friendly mode: both cognitive therapy and breathing therapy are of possible benefit, and they have comparable results in terms of effectiveness. Only the breathing therapy, though, actually reversed some of the hyperventilation seen in panic and anxiety attacks.

Do you need capnometry or sophisticated technology to learn to regulate your breathing, though? In my opinion and experience: no. Learning and rehearsing diaphragmatic breathing can produce the type of benefit reported above. The “trick,” if there is one, is to treat this as any other skill: it requires practice to develop. Practice the technique daily so that you learn to go into a deeply relaxed state quickly. If a normal breathing rate for adults is 12-18 breaths per minute, I encourage people to try to slow down their breathing rate to about 6 breaths per minute, with more time spent exhaling slowly than inhaling (exhale twice as long as you inhale). Even if you can’t get to 6 breaths per minute, learning to breathe out sloooooowly and evenly is a skill that you can access when you start to feel stressed or anxious.

If you would like to practice a breathing-based relaxation technique, you can find some simple instructions on my main web site in the article called, “Relax!“

Adult Outcomes of Childhood Dysregulation: A 14-year Follow-up Study

A study  by Denis G. Sukhodolsky, Ph.D. and his colleagues looked at whether dysregulation in childhood predicts problems in adulthood.   Their data suggest that anxiety and disruptive behavior in youth predicts problems in adulthood.  Here is the abstract of the research report:

Objective
Using a general population sample, the adult outcomes of children who presented with severe problems with self-regulation defined as being concurrently rated highly on attention problems, aggressive behavior, and anxious-depression on the Child Behavior Checklist–Dysregulation Profile (CBCL-DP) were examined.

Method
Two thousand seventy-six children from 13 birth cohorts 4 to 16 years of age were drawn from Dutch birth registries in 1983. CBCLs were completed by parents at baseline when children from the different cohorts were 4 to 16 years of age and sampled every 2 years for the next 14 years. At year 14 the CBCL and DSM interview data were collected. Logistic regression was used to compare and contrast outcomes for children with and without dysregulation, as measured by the latent-class–defined CBCL-DP. Sex and age were covaried and concurrent DSM diagnoses were included in regression models.

Results
Presence of childhood CBCL-DP at wave 1 was associated with increased rates of adult anxiety disorders, mood disorders, disruptive behavior disorders, and drug abuse 14 years later. After controlling for co-occurring disorders in adulthood, associations with anxiety and disruptive behavior disorders with the CBCL-DP remained, whereas the others were not significant.

Conclusions
A child reported to be in the CBCL-DP class is at increased risk for problems with regulating affect, behavior, and cognition in adulthood.

Journal of the American Academy of Child & Adolescent Psychiatry (49:11,  1105-1116.  (November 2010)

What’s the most disabling co-morbid condition for individuals with Tourette’s Syndrome?

Sometimes research confirms my impressions based on clinical experience, other times it surprises. Here is a press release from the University at Buffalo about a new study where the results might at first blush seem somewhat surprising, but may be accounted for by the age of the research participants:

An assessment of patients with adult Tourette syndrome (TS) to identify clinical factors that contribute to psychosocial and occupational disabilities resulting from the vocal or motor tics that define TS found that anxiety/panic disorder may be the most disabling psychiatric condition associated with the disorder.

The results of the study, based on the Global Assessment of Functioning (GAF) scale, will be used to identify patients who are more likely to have or develop significant disabilities related either to the severity of their tics, or to the psychiatric disorders associated with TS, such as obsessive-compulsive disorder, mood disorders and drug or alcohol abuse.

Results were presented today (June 17) at the 14th International Congress on Parkinson’s Disease and Movement Disorders, being held in Buenos Aires, Argentina, June 14-17.

David G. Lichter, MD, professor of clinical neurology in the University at Buffalo’s School of Medicine and Biomedical Sciences, is first author.

“Our study identified the most significant predictors of disability, says Lichter. “Now having identified these at-risk patients, we can follow them more closely and begin appropriate interventions as early as possible.”

Lichter also noted that the finding of anxiety/panic disorder as the most-disabling psychiatric disorder associated with TS was unexpected.

“The main surprise was that depression was not a major predictor of psychosocial or occupational disability in these patients,” says Lichter. “Depression has been identified as an important predictor of quality of life in TS.

Tics, both motor and vocal, are the primary symptoms of Tourette syndrome. Vocal tics are involuntary sounds, such as whistles, hums, or throat clearing. Complex vocal tics can be repeating words or phrases or involuntary swearing. Motor tics are muscle spasms, such as involuntary eye blinks, shoulder shrugs, repetitive kicking, head jerks, eye darts and nose twitches.

In most patients, tics wane after mid-to-late adolescence. However, the study data indicates that in those patients whose tics persist into adulthood, tic severity remains the primary factor contributing to global psychosocial and occupational disability, according to Lichter.

“In many TS adults, motor tics remain more enduring and prominent than vocal tics and, in our study, motor tics were more severe overall than vocal tics and were more closely correlated with GAF scale score,” says Lichter.

The study involved 66 patients — 45 male and 21 female — who had been followed for an average of 8.2 years at a UB-based TS clinic. They ranged in age from 20 to 80.

Results showed that nearly 32 percent were diagnosed with obsessive-compulsive disorder (OCD), while 62 percent showed OCD behavior. Nearly 29 percent had anxiety/panic disorder with another 21 percent exhibiting anxiety symptoms.

Prevalence of other TS-associated conditions were depression (16.7 percent), depressed mood (12.1 percent), bipolar disorder (12.1 percent), rage attacks and severe self-injury behavior (4.5 percent), childhood ADHD history (33.3 percent), adult ADD (18.2 percent), substance-use disorder (22.7 percent) and psychosis and restless legs syndrome (1.5 percent).

In the future Lichter and colleagues plan to collect prospective data on both quality of life and psychosocial and occupational functioning in TS patients.

“We will look more closely at the interactions of tic severity, mood disorders, substance abuse and social support systems and determine how these issues relate to personal and social/occupational adjustment,” Lichter says.

“We hope this information will help us improve the lives of our TS patients, especially those who are at highest risk for a poor outcome.”

Sarah G. Finnegan, MD, PhD, UB assistant professor of neurology, is co-author of the study.

Note that they are looking at adult occupational and psychosocial functioning. My hypothesis is still that ADHD is the most disabling co-morbid disorder for school-age individuals with Tourette’s Syndrome.

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