Maturational dualism

The theoretical frame MacCormack et al. (2021) read their aging data through, and the interpretive engine behind the age-related-interoceptive-decline page. Where that page catalogues the observation (felt bodily emotion weakens with age), this page names the theory offered to explain it — Wendy Berry Mendes’s (2010) claim that the mind–body coupling which makes emotion feel embodied in young adults progressively loosens across the lifespan.

The claim

Emotion in a young adult involves the body heavily: an emotional event provokes autonomic change, that change is sensed (interoception), and the sensing is part of what the emotion is. Maturational dualism says this coupling is not fixed. Across healthy aging:

• Peripheral nerves demyelinate, slowing conduction and dampening autonomic reactivity (from around mid-life, ~45; Verdú et al. 2000; Palve & Palve 2018).
• Autonomic responses to emotional inductions shrink (Tsai, Levenson & Carstensen 2000).
• Objective interoceptive ability declines (Khalsa, Rudrauf & Tranel 2009 — now first-hand: heartbeat-detection accuracy falls ~30%-of-variance across 22–63 yrs; Murphy et al. 2018).
• So emotions come to involve fewer and less intense internal bodily sensations — the mind’s emotional life keeps running while its bodily substrate quiets, and the two come apart.

The name is a provocation, not a metaphysics. Mendes is not reviving Descartes; she is pointing at an empirical decoupling of two things that start out tightly bound. The dualism is a life-history outcome, not an essence.

Why it is a complement, not a rival, to the standard accounts

Emotional aging already had two dominant explanations, and maturational dualism is pitched as a third that works alongside them rather than against:

• Socioemotional selectivity theory (Carstensen): older adults, sensing time as short, are motivated to prioritize positive over negative emotion.
• Expertise accounts: a lifetime of emotional experience makes older adults better at anticipating, avoiding and regulating emotional situations.

Both are about goals and skills. Maturational dualism adds a physiological route to the same endpoints: if aging bodies supply fewer high-arousal interoceptive signals, then unpleasant, highly activated emotions become both less frequent and easier to regulate — no extra motivation or expertise required, though MacCormack et al. expect all three operate together. It is the body-based leg of the tripod.

How it sits inside the wiki’s constructionism

Maturational dualism is a natural corollary of psychological constructionism, and that is why it lives in Lindquist/Barrett-lineage work. If an emotion is a categorization of afferent bodily signals in light of concepts (core-affect plus conceptualization), then changing the amount or quality of the afferent signal should change the emotion — not by breaking the machinery but by feeding it a quieter body. Older adults, on this reading, increasingly construct emotion from situational/appraised meaning (cognitive-appraisal) as the interoceptive contribution thins — which is exactly the decoupling structure MacCormack et al. found in daily life (interoception decouples from situations but not behaviors; see the study page).

The two-edged consequence

Maturational dualism is the theoretical home of the wiki’s sharpest applied tension, recorded on is-more-interoceptive-awareness-better:

• The good edge. Less high-arousal bodily signal → less frequent, more regulable negative emotion → part of the mechanism behind the well-being of old age (the positivity effect).
• The bad edge. The same fading interoceptive input should starve somatic-marker guidance of affect-based decisions — and older adults do make worse such decisions (trusting scammers, poor financial and health choices; Damasio 1994; Clithero & Rangel 2014). One mechanism, two opposite valuations depending on whether the task rewards a quiet body or needs a loud one. See does-somatic-feedback-guide-decisions.

That the same construct predicts both “emotionally better off” and “worse at gut decisions” is its most attractive feature and its least testable — it can absorb either outcome. Held, like the constructionist theories it descends from, with a note that its breadth is bought at some cost in falsifiability.

What it still owes

The wiki’s two self-report sources measure the felt or represented body; Khalsa et al. (2009) now adds an objective-accuracy one, so the theory’s central premise — that the body’s contribution to emotion quiets with age — has first-hand support on three constructs (knowledge, felt intensity, detection accuracy) rather than being asserted through a single kind of measure. But the crucial link is still not instrumented: none of the three measures the afferent physiology itself, and the demyelination/autonomic-dampening-to-dampened-affect chain remains imported by citation. Khalsa’s objective decline is the closest the wiki gets, and it is exactly the construct where “quieter heart” and “worse perceiver” are hardest to separate — he did not measure stroke volume, so his 30%-of-variance age effect is consistent with a genuinely worse perceiver or a merely fainter signal, which is the same ambiguity the whole theory turns on, in miniature. The decisive test MacCormack et al. name — pharmacologically block afferent feedback (e.g. nadolol) across ages and watch emotional experience — has not been run. Until it is, maturational dualism is a well-motivated hypothesis with converging support across self-report and objective accuracy (MacCormack, Volynets, Khalsa) and no direct evidence that the afferent signal is what changed.