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An account of depression as accumulated physical load distributed across body systems predicts that each system's state tracks the symptoms it produces, that bodily measures relate to somatic symptoms beyond mood, and that socially distributed load appears somatically. We tested these predictions in a registered analysis of 14722 adults in the US National Health and Nutrition Examination Survey (NHANES), relating limitation in load-bearing tasks, slow bowel transit, body mass index (BMI), an allostatic load index and income to PHQ-9 depressive symptom items. Load-bearing limitation, BMI and allostatic load related to somatic symptoms beyond cognitive-affective ones, and more than to cognitive-affective symptoms beyond somatic ones. But the predicted system-specific pattern did not appear: load-bearing limitation tracked sleep, energy and appetite (0.2946) far more than slow transit did (0.0404). Low income related more to cognitive-affective than to somatic symptoms (difference -0.0996). Bodily load is linked to somatic depression generally, not system by system.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 14722 NHANES 2005-2010 adults, limitation in load-bearing tasks is associated with the PHQ-9 psychomotor item more than slow bowel transit is (age-, sex- and cycle-adjusted partial Spearman 0.2038 vs 0.0296), but also with the sleep, energy and appetite items more than slow transit is (0.2946 vs 0.0404; difference -0.2542, 95% CI -0.2762 to -0.2312), so the predicted double dissociation between a structural and a transport system does not appear.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In the same adults, load-bearing limitation, body mass index and a nine-marker allostatic load index are each associated with somatic depressive symptoms after adjusting for cognitive-affective symptoms (partial Spearman 0.1916, 0.0558, 0.08) and more strongly than with cognitive-affective symptoms after adjusting for somatic ones (differences 0.0711, 0.0399, 0.0646; Holm-adjusted p 0.002, 0.016, 0.002), whereas slow bowel transit shows no such specificity (difference 0.0074, 95% CI -0.0209 to 0.0347).
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Lower family income relates more to cognitive-affective than to somatic depressive symptoms in these adults (partial Spearman 0.1275 vs 0.0279; difference -0.0996, 95% CI -0.1299 to -0.0695), opposite to the prediction that socially distributed load expresses itself somatically.

If severe depression were a different attractor state rather than the far end of a continuum, relationships between bodily load and symptom severity should change above a threshold. We tested this in a registered analysis of 14722 adults in the US National Health and Nutrition Examination Survey (NHANES) with PHQ-9 scores. Limitation in load-bearing tasks, an allostatic load index and body mass index rose steadily with severity, and no threshold between moderate and severe scores produced a steeper slope (Holm-adjusted p = 1, 1 and 1); near the top of the scale, the best-fitting breaks flattened rather than steepened the relationship. Height, a negative control, showed no break. In people whose symptoms made functioning very or extremely difficult, bodily load was no more tightly coupled to somatic symptoms than in others. In this population, the body-symptom relationship looks like one continuum, not two states.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 14722 NHANES 2005-2010 adults, limitation in load-bearing tasks, a nine-marker allostatic load index and BMI rise linearly with PHQ-9 depressive-symptom severity across its full range, with no steeper slope above any threshold between 8 and 22 points (wild-bootstrap sup-t tests, Holm-adjusted p = 1.0, 1.0 and 1.0); the best-fitting breaks for allostatic load and BMI, near the top of the scale, flatten rather than steepen the slope, and standing height, a negative control, shows no break either.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: The partial association of load-bearing limitation with somatic depressive symptoms, adjusting for cognitive-affective symptoms, is no stronger in adults whose symptoms make functioning very or extremely difficult (partial Spearman 0.1607, n = 454) than in other adults with symptoms (0.1746; difference -0.0139, 95% CI -0.1036 to 0.0773).

Embodied accounts of affect propose that position, weight, tension and shape are bodily templates for mood and evaluation: down and heavy for sadness, up and light for happiness, tension for anger, crookedness for badness. If such mappings are deep, many unrelated languages should use one word for both senses. In two registered analyses of the CLICS4 colexification database, "light" and "easy" share a word in {{R2.pairs.LIGHT (WEIGHT)|EASY.families_colexifying}} of {{R2.pairs.LIGHT (WEIGHT)|EASY.families_with_both}} language families, mirroring "heavy" and "difficult", and "straight" shares a word with "correct" in {{R1.pairs.STRAIGHT|CORRECT (RIGHT).families_colexifying}} families. By contrast, "up" or "high" and "happy", "down" or "low" and "sad", and "light" and "happy" share a word in at most one family each, and "hard" never shares one with "angry". Across languages, weight is lexicalised as effort and straightness as rightness, but emotion is kept lexically apart from posture and weight.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In CLICS4 v1.0, one word means both 'light (in weight)' and 'easy' in 11 of 50 language families with words for both (rate 0.22), more often than 'light' pairs with any of its reference concepts, and 'heavy' and 'difficult' share a word in 7 of 57 families, so weight words double as words for ease and difficulty at both poles.
• Published, Reproduced.Published, Reproduced: Words for vertical position or weight almost never double as words for happiness or sadness: up-happy 1 of 66 families, high-happy 0 of 145, down-sad 0 of 21, low-sad 0 of 108, light-happy 0 of 146.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: 'Straight' shares a word with 'correct' in 38 of 155 families and with 'good' in 7 of 200, whereas 'crooked' shares a word with 'wrong' in 4 of 113 and with 'bad' in 1 of 171, so the straightness-evaluation link is lexicalised mainly at its positive pole.

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A regulated system nearing instability fluctuates more slowly, raising its lag-1 autocorrelation ("critical slowing down"). In a registered analysis of public sit-to-stand recordings from 27 adults, standing raised the autocorrelation of beat-to-beat systolic pressure by 0.0431 (CI 0.0066 to 0.0761). The rise was not larger with diabetes (probability of a larger rise 0.505, CI 0.2802 to 0.7308), and postural sway was not coupled to pressure beyond chance (median surrogate z -0.028). Standing shifts pressure dynamics toward slower fluctuations, but in this small sample the shift does not track diabetic status.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 27 adults from the PhysioNet Cerebral Vasoregulation in Diabetes sit-to-stand recordings, standing with eyes open raised the lag-1 autocorrelation of linearly detrended beat-to-beat systolic blood pressure relative to the preceding 240 s of sitting, by a Hodges-Lehmann shift of 0.043 (bootstrap 95% CI 0.007 to 0.076), with 19 of 27 participants rising (one-sided Wilcoxon signed-rank p = 0.012; Holm-adjusted across two primary tests p = 0.025).
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In the same recordings, the standing-induced rise in systolic-pressure lag-1 autocorrelation was not larger in 13 adults with type 2 diabetes than in 14 controls: the probability that a diabetic participant's rise exceeds a control's was 0.505 (bootstrap 95% CI 0.28 to 0.73; one-sided Mann-Whitney p = 0.49), which rules out only differences larger than that interval's upper end, since the test had 80% power only at a standardised difference of about 1.0.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: During eyes-open standing, magnitude-squared coherence in 0.05-0.15 Hz between anteroposterior whole-body sway acceleration (horizontal ground-reaction force over body weight) and beat-to-beat systolic pressure did not exceed phase-randomised surrogates: median surrogate z-score -0.03 across 26 participants, 2 of whom exceeded 1.645 (one-sided Wilcoxon signed-rank p = 0.54).