Using neurocognitive and time series data to improve treatment outcomes in depression

This research aims to investigate what happens during the delay that is often experienced between starting antidepressant medication and feeling improvements in subjective mood. Patients with depression may have to wait for up to six weeks before experiencing the positive effects of antidepressant medication. This extended waiting time can be dangerous for patients with severe symptoms of depression, and demotivating in cases where the medication does not work. This is despite the fact that some research shows that antidepressant medication may lead to very early neurocognitive changes, such as increased sensitivity to positive facial expressions.
Previous studies have focused on neurocognitive changes that occur within hours of taking the first dose of antidepressant medication, in healthy volunteers who have never taken the medication before. Thus, less is known about both how antidepressants modify cognition when taken over longer periods, and if the neurocognitive effects are the same in people with depression as in healthy people.
To address this, we will conduct a longitudinal study where we follow primary care patients with depression who are taking antidepressant medication for the first time. Data collection is proposed to take place over a 12 week period, subject to participant burden, which will be explored in a preliminary feasibility study. We will track neurocognitive changes using regular online tests, and monitor patients' mood, and the quality and frequency of their social interactions over time, as positive social interactions have been posited as an important contributor to successful antidepressant treatment response. Diagnostic interviews will be conducted to establish how patients' symptoms responded to the medication. Taken together, these measures will be used to establish the relationship, if any, between neurocognitive changes, social interactions, and the outcome and latency of treatment response.
This study will be one of the first to examine neurocognitive responses to antidepressant treatment in patients with depression and to do so over an extended duration of time. The longitudinal, within-subjects, timeseries methodology will allow us to collect rich and ecologically valid data which has been scarce thus far in this research context.
This research is timely, as although depression is a leading cause of disability worldwide and antidepressant medication is a first-line treatment, little is known about the medication's mechanism of action. Benefits of this research include improved theoretical understanding of early markers of antidepressant treatment response, and antidepressant mechanisms of action. This research holds implications for the feasibility of using early neurocognitive markers as predictors of antidepressant treatment response, which in practice could dramatically reduce the waiting time needed for patients to know if a particular antidepressant medication is suitable for them. By exploring the role of social interaction in antidepressant response, this research also holds implications for the significance of social mental health interventions.