Depressed people's eyes dilate more when emotional topics introduced. (old study)
People whose eyes dilate most have best response to cognitive behavior therapy. (new study)
Taken together these two suggest to me that people who are depressed but still emotionally alive are more likely to respond to CBT. What about those who are disconnected from their emotions? What helps them?
previous studies using fMRI brain scans
Dr. Siegel and colleagues
noticed that depressed patients' pupils dilate more when confronted with emotional topics
published in the April 15 issue of Biological Psychiatry
University of Pittsburgh in Pennsylvania
measure how much the pupil dilates when words that have an emotional connotation are spoken
words: death, guilt
more responsive depressed patients more likely to respond to CBT
most effective treatments for depression (incl CBT) work in ~50%
treatment resistance is a growing problem
being able to form a therapeutic alliance with a patient is also an important predictor of response
n=32 with unipolar depression
measured pupillary reaction to emotional words
16 to 20 sessions of CBT
then assessed 20 patients with fMRI
patients who responded to CBT had lower pupillary responses compared with those who did not respond
those who got better had 0.1-mm less pupil dilation (SD, 0.8) than patients who did not
now working on ways to collect data on pupils easy and inexpensive
make a tool that clinicians can use in office
Biol Psychiatry. 2011;69:726-733.
Abstract Remission Prognosis for Cognitive Therapy for Recurrent Depression Using the Pupil: Utility and Neural Correlates
Greg J. Sieglea, Stuart R. Steinhauera, Edward S. Friedmana, Wesley S. Thompsonc and Michael E. Thasea
Background
Although up to 60% of people with major depressive disorder respond to cognitive therapy (CT) in controlled trials, clinicians do not routinely use standardized assessments to inform which patients should receive this treatment. Inexpensive, noninvasive prognostic indicators could aid in matching patients with appropriate treatments. Pupillary response to emotional information is an excellent candidate, reflecting limbic reactivity and executive control. This study examined 1) whether pretreatment assessment of pupillary responses to negative information were associated with remission in CT and 2) their associated brain mechanisms.
Methods
We examined whether pretreatment pupillary responses to emotional stimuli were prognostic for remission in an inception cohort of 32 unipolar depressed adults to 16 to 20 sessions of CT. Twenty patients were then assessed on the same task using functional magnetic resonance imaging. Pupillary responses were assessed in 51 never-depressed controls for reference.
Results
Remission was associated with either low initial severity or the combination of higher initial severity and low sustained pupillary responses to negative words (87% correct classification of remitters and nonremitters, 93% sensitivity, 80% specificity; 88% correct classification of high-severity participants, p < .01, 90% sensitivity, 92% specificity). Increased pupillary responses were associated with increased activity in dorsolateral prefrontal regions associated with executive control and emotion regulation.
Conclusions
For patients with higher severity, disruptions of executive control mechanisms responsible for initiating emotion regulation, which are indexed by low sustained pupil responses and targeted in therapy, may be key to remitting in this intervention. These mechanisms can be measured using inexpensive noninvasive psychophysiological assessments.
doi:10.1016/j.biopsych.2010.12.041