Working notes on the empirical literature behind behavioral history analysis in clinical contexts — what's well-established, what's contested, what remains an open question. Written for clinicians and clinical researchers; references included.
Forty years of research using the Linguistic Inquiry and Word Count framework have produced a robust set of linguistic markers correlated with depressive episodes — first-person singular pronouns, absolutist words, past-tense orientation. We summarize what's well-replicated, what's overstated, and what an analysis of personal message archives could responsibly extract.
Message timestamp distributions correlate well with actigraphy in studies of student populations. They miss segmented sleep, ignore non-messaging wakefulness, and are confounded by time-zone shifts and shift work. We outline what circadian inferences from messaging are defensible and what claims overreach the data.
Anxious, avoidant, and secure attachment styles produce measurably different patterns in romantic communication: response latency, message length asymmetry, repair-attempt frequency. The signal is real but coarse, and the literature is mostly cross-sectional. We work through what longitudinal text data could responsibly add.
Recency bias, mood-congruent memory, and social desirability are not new findings. Yet clinical practice remains overwhelmingly reliant on retrospective patient self-report. We make the case for behavioral data as a complement — never a replacement — for the therapeutic interview, with the limits of each clearly drawn.
Bringing a patient's behavioral archive into therapy raises questions current professional ethics codes only partially address. We work through informed consent under uncertainty, third-party privacy, the re-traumatization risk of pattern surfacing, and why local-only processing is an ethical commitment, not a feature.