Stanford Scientists Classify 5 Subtypes of Anxiety and Depression
Stanford researchers identify five different types of anxiety, each correlating with the activation of different brain networks.
One of the more informative revelations in our quest to understand autism is the wide ranges that exist in behavior and effect. Journalist Steve Silberman opens his tour de force, Neurotribes, by detailing just how varied what is now known as “the spectrum” can be. One hundred people could feasibly have one hundred different genetic causes, resulting in a popular sentiment in the autism community: “If you meet one person with autism, you’ve met one person with autism.”
Could the same be true of anxiety and depression? We know degrees exist, but types? There’s a giant disparity between feeling jitters and a full-blown panic attack, between being awkward at a party and refusing to ever step foot inside any social gathering. To help us understand such distinctions, a new study from Stanford researchers states at least five different types of anxiety exist, each correlating with the activation of different brain networks.
Led by Katherine Grisanzio, research lab manager in the Neuroscience Research Lab at Stanford Medicine’s Williams PanLab, the study, published in JAMA Psychiatry, could lead to more specific therapies for sufferers of the general terms anxiety and depression—two distinct psychological disorders that share numerous qualities. According to the study, at least 50 percent of individuals suffering from one form display concurrent diagnoses applicable to other categories.
Heterogeneity within each disorder manifests not only at the symptom level but also in underlying behavior and physiology, and this limits the opportunity for health care professionals to understand disease mechanisms and to identify valid biomarkers for disease progression and intervention targets.
Only one-third of sufferers in this spectrum of disorders fully recover, a percentage the Stanford team hopes increases through its work. Data from 420 participants (with a second, independent sample of 381 participants) were collected. The mean ages was 39.8; 61 percent of volunteers were female. Tests included self-reporting, brain maps, and psychiatric diagnostic testing. The researchers were also interested in how social anxiety affects everyday living.
Participants were first classified based on self-reporting their negative mood, anxiety, and stress symptoms. Once placed into subtypes, an independent sample was conducted. Symptom subtypes were then expressed at each participant’s level of behavioral and psychological functioning. Finally, the team investigated clinically meaningful differences in functional capacity of each subtype.
In the study, the team describes the five subtypes as:
Tension: This type is defined by irritability. People are overly sensitive, touchy, and overwhelmed. The anxiety makes the nervous system hypersensitive.
Anxious arousal: Cognitive functioning, such as the ability to concentrate and control thoughts, is impaired. Physical symptoms include a racing heart, sweating, and feeling stressed. “People say things like ‘I feel like I’m losing my mind,” Williams says. “They can’t remember from one moment to the next.”
Melancholia: People experience problems with social functioning. Restricted social interactions further cause distress.
Anhedonia: The primary symptom is an inability to feel pleasure. This type of depression often goes unrecognized. People are often able to function reasonably well while in a high state of distress. “We see it in how the brain functions in overdrive,” Williams says. “People are able to power through but at some time become quite numb. These are some of the most distressed people.”
General anxiety: A generalized type of anxiety with the primary features involving worry and anxious arousal — a more physical type of stress.
If psychiatry and the broader medical world are to make progress on treatment, this field guide is an important step forward. According to Leanne Williams, who runs the lab:
"Currently, the treatments would be the same for anyone in these broad categories. By refining the diagnosis, better treatment options could be prescribed, specifically for that type of anxiety or depression."
In My Age of Anxiety, Scott Stossel notices that the increased rate of SSRI consumption that has occurred in America has only resulted in “substantially higher rates of anxiety and depression.” This one-size-fits all approach to treatment is making people more anxious, and subsequently more depressed, due in part to acclimation to the drug and the inability to properly measure if the drug is even effective in the first place.
Not all is lost. As Joseph Ledoux writes in Anxious, “just as the brain can learn to be anxious, it can also learn to not be that way.” That one-third of sufferers do fully recover is a sign that certain therapies are effective. It might just be a matter of sourcing which one is most beneficial.
Hopefully this research from Stanford will help doctors prescribe better treatments individualized for their patients. There is rarely a silver bullet in science. Until we treat each patient on their own terms we’re not going to see effective therapy on a widespread level. And this has to begin with a reduction in scripts written anytime someone feels a little anxious. More time with each patient and a more comprehensive assessment of their neurological functioning are required.
Derek is the author of Whole Motion: Training Your Brain and Body For Optimal Health. Based in Los Angeles, he is working on a new book about spiritual consumerism. Stay in touch on Facebook and Twitter.