The Delta of Language

Introduction

Mental life fluctuates, changing from moment to moment as the incessant and turbulent flow of thought rages. In 3% of the world’s population, the fragile equilibrium that we all hope to maintain gives way to dynamical changes resulting in psychotic episodes, which after remission tend to recur over time.

Importance of Prediction

A capacity to predict these episodes at a clinically relevant temporal resolution, similar to our capacity to forecast a thunderstorm, would be a major advance in public health. The important difference is that, unlike thunderstorms, psychosis can be prevented.

Research Hypothesis

We test a previously untested and untestable hypothesis:

• Meaning encoded in spontaneous speech, translated into digitalized quantitative features,
• Computationally analyzed with natural language processing (NLP) tools,
• Can serve as a key personalized and interpretable predictor of phase transitions from remission to psychotic relapse.

Methodological Breakthroughs

Addressing this hypothesis requires conceptual and methodological breakthroughs in our understanding of language and what signals its variability can carry for a pathophysiological process. We pursue these breakthroughs with a synergetic combination of:

1. Linguistic insights
2. Neuroimaging insights
3. Psychiatric insights
4. E-health insights

Research Approach

Using a hypothesis-driven approach, we will:

1. Define generalizable language metrics relating to symptom variability cross-sectionally.
2. Identify individually-specific neural signatures of psychosis and remission related to changes in these linguistic metrics, using a dense-sampling approach.
3. Test the metrics retrospectively as predictors of relapse in an independent longitudinal cohort.
4. Take the paradigm from the lab to the patient’s home in a prospective clinical study testing whether we can predict state change before it is catastrophic, at the temporal resolutions clinically required.

Conclusion

DELTA-LANG (ΔLANG) thereby identifies the delta of language – a linguistic change that enables the prediction of clinically significant change before it occurs.