Mitochondrial Psychobiology
What lab studies measured, why the mile comparison remains open and what could be pooled.
Sawai et al. (2007) 44 participants · task phase
DISCERN
Picard’s group found that genetic alterations affecting mitochondrial function changed how mice responded to restraint. Some altered strains had larger corticosterone responses and another had a blunted response. This gives causal evidence in that animal model. A separate experiment found roughly 60% higher energy expenditure in cultured human fibroblasts exposed to glucocorticoids over time. The cell result concerns a prolonged laboratory exposure.
Several adult experiments observed increased oxygen uptake during a challenge relative to rest. In the cycling calibration studies, cardiovascular activity rose more than expected from the oxygen uptake measured during stress. Pulse and perceived intensity cannot substitute for calorimetry. Rest comparisons also include the metabolic cost of doing the task.
Daniel Tawfik supplied the mile comparison. Martin Picard’s quote-post highlighted mitochondrial involvement in the stress response. Hall and colleagues measured about 481 kJ (~115 kcal) during a 1,600 m treadmill run, in a different cohort and protocol. Sawai’s task-only calculation above uses an excess over rest and excludes recovery. The studies therefore do not provide a like-for-like comparison. The running value is a benchmark for planning a study, not an estimate of the difference.
DEEPEN
The 2022 narrative review supplied seven seed reports. Its often-quoted range of approximately 9–67% combines estimates from different tasks and includes oxygen uptake as a proxy. The primary Seematter papers report smaller baseline-condition percentages than the review’s combined 39–45% summary. The discrepancy remains unresolved, so the extraction uses the primary values wherever available.
| Study | Measure and Comparison | Result | Pooling Readiness |
|---|---|---|---|
| Carroll, Turner & Hellawell (1986) ↗24 young men | Oxygen uptake Arithmetic and Raven’s matrices at three difficulty levels, plus cycling calibration | The review reports up to +9% for matrices and about +13% for arithmetic. | Abstract and review checked. Recover the task-level means and paired uncertainty. |
| Sawai et al. (2007) ↗44 male students | Oxygen-derived kcal/min/kg 15 min serial subtraction vs seated rest | 0.018 → 0.023 kcal/min/kg, approximately +28% from rounded means. | Full text checked. Phase-level paired uncertainty needs recovery. |
| Carroll, Phillips & Balanos (2009) ↗24 participants | Oxygen uptake 8 min paced arithmetic vs rest, plus graded cycling | Oxygen uptake rose modestly during the task while cardiac output rose substantially. | Author manuscript checked. Time-series figure available. Recover the paired phase summary. |
| Balanos et al. (2010) ↗22 young men | Oxygen uptake 8 min paced arithmetic vs rest, plus graded cycling | Cardiac output rose more than expected from contemporaneous oxygen uptake. | Author manuscript checked. Figure 2 shows group means and standard errors by minute. Paired phase uncertainty is unresolved. |
| Delarue et al. (2003) ↗7 volunteers | Indirect calorimetry 30 min arithmetic and Stroop vs rest before supplementation | The primary abstract confirms an increase. The review reports approximately +67%. | Primary abstract checked. Verify the percentage, its time window and paired uncertainty in the full report. |
| Seematter et al. (2002) ↗10 and 8 healthy women in two protocol groups | Oxygen uptake 15 min arithmetic and Stroop vs rest under isocaloric feeding | +22% and +19%, each with a reported SEM of 3 percentage points. | Full text checked. Directly usable for the within-paper demonstration, conditional on group independence. |
| Seematter et al. (2000) ↗11 lean and 8 obese women | Oxygen uptake Mental stress vs rest during an insulin clamp | Approximately +20% and +21% in the respective groups. | Primary abstract and indexed results checked. Clamp-specific outcome. Paired uncertainty unresolved. |
SYNTHESISE
Sawai’s oxygen-derived rate difference is 0.005 kcal/min/kg. Multiplying by 15 minutes and the reported mean body mass of 66.9 kg gives about 5.0 kcal above rest for that illustrative participant. The multiplication uses rounded group means, so it does not recover the sample mean of individual excess calories or its uncertainty.
Combining Seematter’s two isocaloric protocol groups with inverse-variance weights gives +20.5% oxygen uptake (approximate 95% interval +16.3% to +24.7%). Both groups have SEM 3 percentage points, yielding a combined SEM of 2.12. This normal-approximation calculation assumes independent groups and a shared underlying effect. It is an exploratory estimate from a single paper with 18 women across the two groups.
The accessible records did not yield enough independent, comparable adult energy-expenditure contrasts with recoverable paired variances to support a cross-study pooled result. The positive lab signal is informative. A single summary would currently mix different outcome units, conditions and controls.
Screened the names, roles, descriptions and relevance notes of all 158 Source Atlas entries across 11 categories (v0.2, directory updated 9 November 2026). Broad biomedical, neuroscience, metabolism, physiology and stress terms flagged 11 entries. The narrower mitochondrial, allostatic-load and calorimetry terminology produced no direct catalogue matches. Indexed papers were then traced through the relevant discovery routes and citation lists. The catalogue screen measures coverage of source families, while the extraction table records the papers actually checked.
S022 · Crossref / CrossmarkS023 · PubMed / PMCS035 · Nature / SpringerS037 · Elsevier / ScienceDirectS043 · Wiley
Broad keyword hits: S007, S023, S028, S036, S058, S091, S130, S133, S135, S138 and S139. Core terms for the study search included psychological stress, mental arithmetic, Stroop, oxygen consumption, indirect calorimetry and energy expenditure. The review supplied the seven seed reports. Citation chasing and targeted searches supplied the additional leads. Screening and extraction were single-pass and await independent verification.
The earlier work considered mitochondrial signalling, interoception and the biological conditions that support experience. The present result gives that conversation a narrower physiological question. It leaves the role of mitochondria in producing or shaping conscious experience open.
Boundless Awareness ↗Multiscale Consciousness ↗N2N Mitochondria Deep Dive ↗N2N Mitoception Archive ↗EXPAND² Method ↗
