BERM · Understanding the explanation
Proxy masking: how an underlying effect becomes hidden
Why a correlated measure or a real contributing cause does not explain the whole causal chain — and what follows from BERM’s premises.
An animal gains weight. It eats more, so increased food intake explains the weight gain. But why did its appetite change? Food intake can be both a real cause of weight gain and an intermediate step in a longer biological process. An explanation can be correct while leaving the beginning of the chain unresolved.
A proxy is an indirect measure: something we can observe in place of a harder-to-measure process. Here, masking means that an earlier effect becomes hard to recognise behind a correlated measure, an intermediate biological change or the way the outcome is recorded.
BERM places the electromagnetic field upstream of receiving biology, regulation and behaviour. In this model, diet, stress and lifestyle describe later stages or conditions of the same chain. They explain parts of an outcome while leaving the origin of the biological change unidentified. BERM connects these parts to an explicit physical starting point.
The central conclusion
A real contributing cause does not, by itself, explain the origin or the full extent of the effect.
An explanation within a longer chain
Before interpreting a correlation, ask what role each variable plays. The same word — such as lifestyle — can refer to an environmental input, a behavioural consequence or a broad label that combines many processes.
The proxy follows the outcome, but the curve does not identify the causal path. Reveal BERM’s field branch below and compare a shared environmental change with an effect transmitted through a biological intermediate.
Causal illustration
Similar curves can conceal different causal paths
The outcome and its proxy move together. Show BERM’s field pathway, then switch the causal case: the same curves can have different explanations.
Both axes are unitless.
The outcome and proxy are visible. BERM’s field pathway is hidden.
The causal structure behind the curves
Technological development
Technology-use indicator
The proxy and outcome change together. This association alone does not identify what links them.
Outcome
In this BERM pathway, technological development changes the proxy and the field in parallel. The effect passes through field → reception → outcome. The proxy follows the outcome while leaving its biological origin unidentified.
What follows from the premises
A proxy does not identify the effect’s origin
A proxy that tracks a shared environmental change predicts the outcome through that common cause. Calling the proxy the explanation leaves the intervening biological pathway unresolved.
A real proximate cause still has an origin
Increased eating causes weight gain while the change in appetite still needs explaining. Holding an intermediate fixed excludes the pathway through it from the effect being examined.
One exposure’s effect can include another’s contribution
In an interaction, the chemical’s response includes a component that depends on field conditions. The chemical remains a real cause, but its concentration alone does not explain the response’s size.
A category or recorded trend is not a mechanism
Urbanisation combines exposures, resources and behaviour under one label. Recorded prevalence also includes detection and classification, so its change does not by itself identify a biological pathway.
Open the mathematical derivation of the proxy argument
A common cause creates the association
Environmental change U affects proxy P and field input E. In this pathway, E acts through biological state B on outcome Y; the association with P does not pass through an effect of P itself.
The total effect includes the intermediate
M is the intermediate. The total derivative includes both the direct effect and the effect transmitted through M. Holding M fixed removes the second term from the comparison.
The chemical response depends on field conditions
C is chemical exposure. For an interaction with γ ≠ 0, the response to C at fixed E is β_C + γE. The sign of γ belongs to the specified chemical, tissue and protocol; it is not assigned to all combinations.
Recording is a separate step
R describes detection and recording. The recorded outcome depends on biological outcome Y and the observation process, which need to be distinguished when interpreting a trend.
These equations describe effects in the specified causal model. Interpreting observational regression coefficients as those effects additionally requires identification assumptions.
A correlation does not identify the causal path
Prosperity, urban living, screen use, diet and family planning do not answer the same causal question. BERM locates each variable in the chain: a shared environmental change, a biological intermediate, an interaction or a recording process. Treating all of them as self-contained explanations hides these differences.
A correlated proxy shares variation with an exposure. A mediator carries part of a causal effect. A modifier changes the response to an exposure. Keeping these roles distinct makes the claim of masking concrete.
Explore an explanatory variable
Select a variable to see the reasons for shared change, the part it explains and the longer causal chain that BERM identifies.
A broad measure of resources and living conditions.
GDP and prosperity
- Why can they change together?
- Electrical networks and devices support production and everyday consumption. Their spread can change both economic indicators and the field environment.
- What does this explanation leave unresolved?
- A GDP–outcome correlation does not identify the field input. Attributing the whole association to prosperity leaves the physical pathway unnamed.
- Why this is not a complete explanation
- In the high-income United States, two Amish datasets produced total fertility rates just above six children per woman. National prosperity alone therefore does not determine a community’s fertility. Stone 2025i.
- What does the BERM explanation add?
- BERM derives a path from local physical input through receiving biology to the outcome. Resources retain their own effects, but an income measure does not identify this field-dependent part of the chain.
Connection to the evidence
Electricity access was associated with fertility in regional data; EMF dose was not measured. Belmin 2022i.
This analysis follows the BERM premises stated above. Each variable’s causal role, the basis for shared change and the relevant empirical evidence are presented separately.
From a use proxy to a measured field
The missing exposure does not have to remain an abstract objection. Human studies have measured personal magnetic fields, compared phone-use groups and adjusted for conventional explanatory variables. They constrain different parts of the exposure–response connection.
Personal field measurement: an association with semen quality
Li’s participants wore a personal magnetic-field meter. A 90th-percentile exposure of at least 1.6 mG (0.16 µT) was associated with poorer motility and morphology: adjusted odds ratio 2.0, 95% CI 1.0–3.9. Longer time above that field level strengthened the association (trend p = 0.03). The field is measured here, rather than assigned from a lifestyle label. Li 2010i.
Phone use and sperm concentration
Rahban’s Swiss study recruited 2,886 young men; 2,759 answered the use-frequency question. These are the published group medians, before statistical adjustment. Rahban 2023, Table 1i.
Median sperm concentration · million/mL
- Less than once/week (n = 223)56.5
- 1–5 times/day (n = 667)47.9
- 5–10 times/day (n = 592)45.0
- 10–20 times/day (n = 669)47.1
- More than 20/day (n = 608)44.5
The association with total sperm count remained in a model accounting for education, smoking, body mass index and sampling conditions. Phone use therefore contained information beyond those variables. The study did not isolate how much of that information came from RF exposure.
The use–concentration association was more pronounced in 2005–2007 and weaker in later periods. The authors connect this pattern with changing phone technology and output power. This is particularly relevant to BERM: an equal count of uses need not mean an equal physical input to the receiver.
Study design, dispersion and adjusted estimates
Li’s field measurement describes an observation period, not a measured lifetime dose. Rahban measured self-reported use, not individual RF dose. For >20 uses/day versus 1–5/day, adjusted coefficients on the cube-root scale were −0.152 (95% CI −0.316 to 0.011) for concentration and −0.271 (−0.515 to −0.027) for total count. Overall trend tests gave p = 0.021 and 0.010. Motility, morphology and pocket storage showed no consistent adverse association. Period-specific adjusted estimates had overlapping confidence intervals.
Published concentration interquartile ranges, in the same group order (million/mL): 27.5–105.2; 25.2–89.0; 19.8–88.4; 23.0–85.0; 21.4–80.9.
Energy access retains an association with fertility
Across 155 Demographic and Health Surveys from 1990–2015, greater electricity access remained associated with lower total fertility after accounting for women’s education, urbanisation, GDP, age at marriage and conflict. The analysis used region fixed effects, five-year period controls and standard errors clustered by region. Belmin et al. 2022, Table 1i.
| Model | Coefficient (SE) | Sample |
|---|---|---|
| M1 · electricity + controls | −0.018 (0.003) | 1,356 observations · 403 regions · 44 countries |
| M3 · electricity + modern cooking fuels + controls | −0.008 (0.004) | 940 observations · 319 regions · 36 countries |
Adding modern cooking-fuel access changes the electricity coefficient; that model also uses a smaller sample. Shared variation and distinct energy-related pathways matter, so the coefficient difference is not a pure measure of mediation.
This is the proxy problem in concrete form: an infrastructure variable tracks several changes at once. In BERM, the field branch belongs within this changing environment. Education and other mediators retain their causal roles; their inclusion does not identify which upstream input produced the biological component. The study measures energy access, while the field-specific interpretation is BERM’s composition.
BERM synthesis
Level 1: the unmeasured reserve and the missing interaction
BERM connects reserve loss to statistical masking through the choice of outcome, timing and conditioning variables. If reserve is unmeasured and only the final challenge is recorded, the observed loss of function may be attributed entirely to that challenge. The biological reserve and its statistical visibility are separate stages of this explanation.
Component experiment
Same hormone stimulus, no additional oxidant
In Chen’s MA-10 cells, depletion of reduced glutathione (GSH) by more than 80% could leave LH-stimulated progesterone production preserved without the added oxidant.
Component experiment
Same hormone stimulus, with an oxidant challenge
Adding the oxidant exposed greater steroidogenic vulnerability in the depleted cells. The comparison concerns a measured reserve and a specified challenge, not an inferred hidden injury in every unchanged result.
Preserved production can be real: a reserve may be consumed before output fails. An insensitive assay is another possible observation problem, requiring its own detection limits. These two explanations must not be counted as the same finding.
The field-to-reserve link and reserve-to-function link come from different experiments. Miao measured GSH/GSSG changes and GSH in RF-exposed TM3 cells; Chen manipulated glutathione in MA-10 cells and measured progesterone under LH stimulation. Their connection is BERM synthesis through a shared biological state, not an end-to-end EMF–hormone experiment.
Miao et al. (2025)iField experiment
Timing adds a second observability problem. In Houston’s mice, ROS approached control levels during continued exposure while DNA damage persisted. Thus current ROS, accumulated damage and functional output should remain separate observations.
Houston et al. (2019)iRead the protocols, research families and reserve model →A familiar label can conceal different physical exposures
A screen-use measure can combine optical light, RF exposure, posture and content. Personal RF exposure correlated more closely with local measurements and combined models than self-ratings or transmitter distance. In children and adolescents, modelled tissue dose depended on device use and network technology. Screen time alone therefore does not specify RF dose: the field contribution needs its own exposure description. Frei 2010i; Birks 2021i.
The same cue, a different receiver
Organisms constantly use environmental cues: a scent, a call, the timing of light or a flower’s electrical properties. A cue has an effect when a receiving system detects it and gives it biological significance. That receiving system changes with physiology and experience.
The same sensory cue can produce different responses when the receiver’s hormonal or neural state changes.
Same cue, different reception
Keep the cue fixed and change only the receiving state. Compare the strength and timing of the resulting response.
The reference state gives a relatively strong, early response.
Human sensory cues meet a changing receiver
A cue is not its effect. Human experiments separate the incoming stimulus, the receiver’s state and the resulting response. BERM connects these stages instead of treating social contact or a reported preference as a complete explanation.
Infant odour and biological significance
Unfamiliar newborn odour elicited reward-related brain responses in 15 first-time mothers and 15 nulliparous women; responses differed with maternal status. This is human sensory processing, rather than a measured desire to have children. Lundström 2013i.
Touch and hormonal state change interaction
In a placebo-controlled crossover experiment involving 35 fathers, oxytocin administration changed father–infant interaction and parallel infant responses. In another experiment, partner handholding reduced threat-related brain activation in 16 women. Social input and biological response are connected experimentally. Weisman 2012i; Coan 2006i.
The same hormonal input, a different response
Evening eReader light altered melatonin and circadian timing. Separately, eight women received the same kisspeptin dose in different menstrual phases: the LH response was strongest before ovulation. Light history and reproductive state therefore enter at distinct, measurable points. Changi; Dhillo 2007i.
BERM composition: field-dependent receiving state changes the weight of odour, touch and social signals. The model connects light–melatonin timing with kisspeptin–GnRH regulation and its measured LH output. The human field-to-reception link is an explicit conditional bridge; its magnitude is not supplied by these sensory experiments.
A feedback path through everyday contact
- Contact with infants
- Sensory input and learning
- Later interaction and contact
BERM carries this loop into reproductive motivation: changes in contact alter the cue stream and learning history, which influence subsequent interaction. The demographic extension is model composition. Infant odour is not assigned to an established human pheromone receptor.
A chemical signal can regulate reproduction
In naked mole-rats, a queen-associated odour compound, isopropyl myristate (IPM), maintained reproductive suppression after the queen was removed. This identifies an external chemical signal capable of maintaining a reproductive state in a mammalian community. The experiment did not manipulate electromagnetic exposure. Khallaf 2026i.
A hormone can change the meaning of a call
In mice, oxytocin altered the processing of pup calls in the auditory cortex and facilitated maternal responses. Related circuit experiments located part of the social learning of care. These are direct interventions in sensory processing and behaviour. Marlin 2015i; Carcea 2021i.
Light both signals and prepares the receiver
Light is electromagnetic radiation. Separating optical, extremely low-frequency (ELF), intermediate-frequency (IF) and radiofrequency (RF) exposure makes their absorption and reception measurable. Their biological interactions still belong in the same account.
An immediate signal
A light-absorbing molecule initiates a response to the current illumination.
A prepared state
Illumination changes photochemical or redox state, which can shape a subsequent field response.
A biological history
Earlier light exposure changes circadian phase, hormonal signalling and protein expression.
In Arabidopsis, magnetic enhancement of a cryptochrome response occurred when the field was applied during dark intervals following blue light. In mouse muscle cells, dark culture weakened a response to a pulsed magnetic field, as did CRY2 or riboflavin-kinase knockdown. These studies identify light history and molecular state within their own exposure protocols. Hammad 2020i; Iversen 2025i.
An ELF study found different changes in oestrogen-receptor expression across reproductive-cycle phases in the rat olfactory bulb. A separate cell experiment measured altered MT1-associated hormonal signalling. In BERM, these measurements constrain the link between field input and receiving state; the sensory interventions above constrain the next link from that state to behaviour. Reyes-Guerrero 2010i; Girgert 2010i.
When exposures act together
An exposure can be measured accurately while an important part of its action remains hidden. The amount outside a cell, the amount entering it and the cell’s response to that amount are different quantities.
Chemical exposure, transport into the cell and receiving state can jointly shape an outcome; a single exposure measure may leave a co-condition unrecorded.
In a cadmium experiment, calcium-channel agonists and antagonists changed cellular uptake and toxicity. This pharmacological result shows why the same external concentration need not mean the same internal dose. The experiment itself contained no field exposure. A separate mouse study directly combined a 50 Hz magnetic field with lead and measured antioxidant and membrane responses. These interventions locate different parts of the chain: transport, internal dose and the response to combined exposure. Hinkle 1987i; Liu 2002i.
A chemical effect can depend on the receiving state
Follow the chemical input along the horizontal axis. Change the context to see how the same input can produce a different response.
In the reference context, response increases along the reference curve.
Three measured components, one assembled mechanism
RF, the blood–brain barrier and internal metal dose
Tissue metal exposure depends on transport as well as blood concentration. Three experimental components connect RF, transport and chemical-specific toxicity.
RF changes uptake and barrier-related transport
Pulsed 2.45 GHz increased tracer uptake into brain capillary endothelial cells; colchicine almost abolished uptake. Separately, GSM-900 exposure increased albumin extravasation. Neubauer 1990i; Nittby 2009i.
The field branch reaches a transport-related biological process.
A transport intervention changes metal entry into the brain
Methionine and BCH reduced brain uptake of radiolabelled methylmercury–L-cysteine by competing with amino-acid transport. Entry depended on the metal’s chemical form and transport pathway. Kerper 1992i.
Blood concentration alone does not determine the metal’s entry into tissue.
RF modifies a chemical-specific toxic response
In mouse embryonic fibroblasts, Cr(VI) pretreatment followed by 1800 MHz RF at SAR 4 W/kg increased DNA damage. Cadmium, hydrogen peroxide and 4NQO did not show that additional response. Zhu 2026i.
The combined effect depends on the chemical and biological conditions.
BERM connects transport to internal dose
Transport controls internal exposure; RF changes transport-related processes and metal-related damage under the studied protocols. BERM connects these components through a metal-form-specific transfer coefficient dependent on field input and receiving state.
- Jⱼ
- Inward metal flux per unit tissue volume: amount / volume / time.
- Tⱼ
- Transfer coefficient for metal form j, normalised to tissue volume: 1 / time.
- C_blood,j
- Blood concentration of the transportable metal form j: amount / volume.
- E, S
- The specified field input and the receiving tissue’s state.
Holding blood concentration and receiving state fixed, the field dependence of influx follows the field dependence of the transfer coefficient:
Tⱼ(E, S) is BERM’s composed field-sensitive link. Its metal-specific magnitude and sign remain to be calibrated. This local linear approximation describes influx; tissue accumulation also depends on clearance.
Why a metal-only explanation misses part of the chain
At the same blood concentration, a change in the transfer coefficient changes the inward metal flux. The metal remains a causal exposure, while the measured metal–outcome relationship incorporates the conditions governing entry and response. BERM makes the field-dependent part of those conditions explicit.
Where Wi-Fi enters the model
BERM includes Wi-Fi in the RF input family using its actual spectrum, modulation, traffic pattern and timing. The Wi-Fi application is derived here from the RF components through BERM; the cited experimental protocols used laboratory pulses, GSM-900 and 1800 MHz exposure.
Study protocols and what each endpoint measures
Neubauer 1990 · endothelial uptake
Male rats; 2.45 GHz, 10 µs pulses at 100 pulses/s, 10 mW/cm², SAR approximately 2 W/kg, 30–120 minutes. The endpoint was rhodamine–ferritin uptake into cortical capillary endothelium, not metal delivery into brain tissue. Neubauer 1990i.
Nittby 2009 · albumin extravasation
Forty-eight rats; GSM-900 for two hours, SAR 0–120 mW/kg, assessed seven days later. Pooled extravasation increased; the dose-specific difference was at 12 mW/kg. Albumin passage is distinct from metal flux. Nittby 2009i.
Kerper 1992 · methylmercury uptake
Anaesthetised rats received rapid carotid methylmercury–L-cysteine infusion. Uptake was partly saturable. The inhibited amino-acid route differs from endothelial tracer uptake and albumin leakage; there was no field intervention. Kerper 1992i.
Zhu 2026 · DNA damage
Fibroblasts; 12-hour chemical pretreatment, then 1800 MHz RF, SAR 4 W/kg, for 15 minutes. RF alone produced no detectable damage. Genotoxicity was measured, not the blood–brain barrier or metal transport. Zhu 2026i.
Cosquer 2005 · no detected leakage
Rats; 2.45 GHz, 2 µs pulses at 500 pulses/s, 45 minutes, whole-body SAR 2 W/kg, average brain SAR 3 W/kg. No Evans blue leakage was detected. Signal, timing and endpoint therefore remain part of the transport specification. Cosquer 2005i.
A chemical effect can travel through an electrical cue
Fertiliser treatment changed floral electrical cues and reduced bumblebee foraging. Chemical exposure and electrical signalling were parts of the same studied process. This is a concrete example of how identifying the chemical does not finish the explanation of how the behavioural effect occurs. It does not establish an external RF cause for that process. Hunting 2022i.
When compensation preserves function
An organism often has more than one way to perform a task. A bird can use celestial cues as well as magnetic information. A stable final result may therefore coexist with changes in how that result is achieved.
The observed endpoint depends on the available pathways and their compensation, as well as on the state of the pathway being examined.
Garden warblers retained seasonally appropriate orientation under an oscillating magnetic field when stellar cues were visible. The result is consistent with the use of an alternative cue. The experiment did not simultaneously demonstrate receptor-level magnetic disruption in those same birds. Bojarinova 2024i.
One channel
The response depends on a particular sensory pathway.
Several channels
Alternative cues can contribute to the same task.
The recorded outcome
Direction or performance alone does not identify the contribution of each channel.
What other species reveal
Other species help separate biological mechanisms from explanations that require specifically human institutions or conscious choices. The most informative comparison names the organism, the function and the exposure actually studied. Here, a sentinel is a species whose particular function can help reveal an environmental effect.
Cross-species observations can extend the causal question beyond human choices to biological regulation and shared material environments.
Klimentidis and colleagues assembled data on more than 20,000 animals from eight species. Weight trends were positive in all 12 populations when sexes were combined. Laboratory diets were broadly stable in composition, but intake and activity were not universally held constant. The result opens the question of why energy intake or use changes; the study did not measure EMF exposure. Klimentidis 2010i.
Explore the Klimentidis comparisonSentinels selected for a function
European robin
What was measured Magnetic-compass orientation during changes in RF noise.
What it contributes A direct functional field response; orientation is the endpoint.
Bumblebee / flower
What was measured Floral electrical changes and foraging after chemical treatment.
What it contributes A chemical → electrical-cue → behaviour connection.
Honeybee
What was measured Flower landings under manipulated local electric fields.
What it contributes A direct intervention in an ecologically relevant behaviour.
Garden warbler
What was measured Orientation with stellar cues available during RF exposure.
What it contributes Alternative cues and the interpretation of preserved function.
Broadcast-spawning corals
What was measured Spawning dates associated with artificial light at night.
What it contributes An optical timing association; fertilisation loss was not measured in this global dataset.
Naked mole-rat
What was measured Reproductive suppression during a queen-associated odour intervention.
What it contributes A reference system for sensory reproductive regulation; EMF sensitivity was not tested.
A shared mechanism makes animal evidence informative
A sperm cell does not acquire its energy supply or DNA repair from a country’s GDP. Conserved biology lets animal experiments identify components of a human mechanism. The strongest bridge compares the same process, exposure and outcome directly.
71%
Among 221 human toxicity events for 150 drugs selected for known human toxicity, at least one animal species showed concordant toxicity. This measures detection of human toxicities, not the chance that any animal result transfers. Olson 2000i
RR 0.86
For 62 selected therapies, a meta-analysis compared proportions of positive clinical and animal studies: pooled risk ratio 0.86 (95% CI 0.80–0.92). This supports informative translation; it is not an 86% replication probability. Ineichen 2024i
Carry the evidence across species through a conserved target, a comparable internal exposure and the same endpoint. Then account for species and physiological state. These links give component studies evidential value without treating every animal finding as a human outcome.
Three published sperm trends, with their actual units
Declines in human, dog and horse samples extend the question beyond human decisions. Each study measures a specific endpoint and population; the numbers below preserve those differences.
| Population | Period | Measured change |
|---|---|---|
| Humans: unselected Western subgroup | 1973–2011 | Sperm concentration 99.0 → 47.1 million/mL (−52.4%); 110 estimates in this subgroup. |
| Dogs: one UK breeding programme, 232 males | 1988–2014 | Progressive motility fell at reported rates of 2.5%/year in 1988–1998 and 1.2%/year in 2002–2014; breeding selection separated the periods. |
| Horses: 230 estimates from 229 articles | 1984–2019 | Model-estimated progressive motility 63.69% → 42.35% (−33.51%); slope −0.610 percentage points/year. |
These are measured semen trends, not matched field-dose measurements. Together they motivate a shared biological explanation; they do not yet identify which shared exposure caused the historical changes.
A historical trend and an experiment answer different questions
In seven dogs, a 10-week phone-exposure protocol (1962–1966 MHz, two hours/day, five days/week) produced no significant semen change relative to baseline. Phones were on the chest; 0.96 W/kg was the manufacturer’s rating, not measured testicular exposure. Dong 2022i
In eight stallions’ samples, a 2.4 GHz REAC device with electrodes immersed in the medium preserved DNA and acrosome integrity during 72 hours of cold storage; progressive motility did not improve. This tested the combined device intervention. Berlinguer 2017i
These results locate protocol-dependent responses. Neither experiment measures the historical exposure of the populations in the trend table.
What a group label contains
A community name can bundle lighting, work, movement, microbes, technology use and reproductive practices into a single variable. The group difference is a starting point for identifying those material pathways.
A lifestyle or community label can predict an outcome while concealing differences between the exposures and biological processes included in that label.
In an Ohio comparison, Amish adults reported less exercise undertaken for health, while step counts indicated greater overall movement. The male comparison below shows why the purpose of an activity and its total physical amount are different measures. Katz 2012i.
Two activity measures, opposite group order
Compare the order of the two groups in each panel. One measure asks why people exercise; the other records how much they move. Each has its own scale.
Intentional exercise for health
Share reporting this activity (%)
Daily steps
Age-adjusted mean steps/day
From a community label to a transferable exposure
An Amish–Hutterite study went further: household dust, immune measures and a mouse asthma model were examined together. The protective effect of Amish dust in mice depended on named innate-immune signalling. Part of the group contrast thus gained a material, experimentally investigated pathway. This was a dust and immunity study, not a measured EMF contrast. Stein 2016i.
From biological state to a reported reason
People describe decisions through what they experience: energy, interest, stress, closeness, opportunity and practical constraints. Those descriptions can be sincere and consequential even when the person cannot observe every process shaping the experience.
A reported reason can describe a meaningful downstream state while leaving its biological and environmental history unresolved.
BERM places perceived meaning and motivation within a continuous biological and social chain. A change in responsiveness can alter what a cue feels like; experience influences behaviour; repeated behaviour changes social contact and the cues encountered next. Human motives, learning and material constraints remain explicit parts of that chain.
The interpreter: a reason does not identify its origin
Gazzaniga’s interpreter account describes how explanations are assembled from available information. His split-brain example involves a patient explaining a shovel choice without verbal access to the snow scene that prompted it. Gazzaniga 2000, reviewi.
Johansson’s participants sometimes justified a secretly substituted face choice. Desmurget’s direct cortical stimulation dissociated movement intention, movement and awareness in seven surgical patients. These interventions locate limits of introspective access; they do not make every reported reason a post-hoc account. Johansson 2005i; Desmurget 2009i.
A reported major reason
In Pew’s 2024 survey, 57% of US adults aged 18–49 who had no children and considered future parenthood unlikely said simply not wanting children was a major reason. This selected group contained 770 respondents. The percentage describes their answers, not all childless adults. Pew 2024i.
BERM connects physical and biological state to valuation, experienced motivation and the reason subsequently reported. The report describes one stage of that chain; it does not identify the upstream state. The Pew percentage is not a biological diagnosis.
Biological state, valuation and reported reasons →Caregiving, sexual motivation, desire for children, ovulation and pregnancy are distinct outcomes. The sensory studies support particular transitions; combining them into an EMF-to-human-reproductive-behaviour pathway remains BERM’s conditional synthesis. The model does not need to assume that every participant gives the same reason or responds in the same direction.
Reproductive regulation · behaviour · feedback
Eight axes become a joint measurement problem
Care allocation, contact, stress, courtship, signalling, social regulation, hormone dynamics and effort occupy different positions in the causal sequence. Existing studies already combine some of them within the same people. Connecting these measurements recovers information lost when each outcome is assigned a separate social explanation.
Follow the three branches and their evidenceFragmentation of a behavioural profile
Syndrome fragmentation: eight comparison axes
A shared receiving state can express itself through several functions. If each outcome is analysed under a different social label, the joint pattern disappears. BERM uses the following cross-species mapping to keep those functions together.
BERM model mapping · component-specific evidence
Animal function: Allocation of caregiving
- Human measure
- Caregiving time; infant and pet contact
- Conventional explanatory label
- Pet parenting; family lifestyle
- What BERM integrates
- Cue salience, attachment and available effort. Pet care alone does not demonstrate displaced reproduction.
Animal function: Dispersal and social proximity
- Human measure
- Contact frequency; isolation; household moves
- Conventional explanatory label
- Atomisation; urbanisation
- What BERM integrates
- Social reward, perceived threat and the opportunities for contact.
Animal function: Stress response
- Human measure
- Cortisol dynamics; threat responses; anxiety measures
- Conventional explanatory label
- Work pressure; insecurity
- What BERM integrates
- Stress physiology and the receiving state in which the same challenge is encountered.
Animal function: Courtship and sexual motivation
- Human measure
- Desire scales; sexual activity; partnership formation
- Conventional explanatory label
- Sex recession; screen time
- What BERM integrates
- Hormonal response, reward valuation and partner opportunities as distinct contributors.
Animal function: Production and reception of signals
- Human measure
- Responses to odour, voice and touch
- Conventional explanatory label
- Dating culture; communication habits
- What BERM integrates
- Signal availability and receiver sensitivity without inferring pathology from gender expression.
Animal function: Social regulation of reproduction
- Human measure
- Norms, sanctions and support for parenthood
- Conventional explanatory label
- Pronatalist or antinatalist views
- What BERM integrates
- How social feedback alters costs, contact and later choices. A belief is not a clinical marker.
Animal function: Hormonal reorganisation
- Human measure
- Hormone dynamics and reproductive function
- Conventional explanatory label
- Age; lifestyle
- What BERM integrates
- Hormone levels, receptor responsiveness and timing. Paternal adaptation and reproductive impairment are different outcomes.
Animal function: Risk, exploration and effort
- Human measure
- Risk choices; effort tasks; everyday mobility
- Conventional explanatory label
- Passivity; driving-licence trends
- What BERM integrates
- Energy, stress and reward weighting alongside money, policy and practical constraints.
Human component anchors include oxytocin-dependent interaction, sleep-related social withdrawal, kisspeptin-sensitive sexual responses, fatherhood-associated hormonal change and dopamine-dependent effort choices. Weisman 2012i; Ben Simon 2018i; Mills 2023i; Gettler 2011i; Westbrook 2020i.
The eight rows are comparison axes, not a measured eight-part diagnosis or proof that population trends share one cause. BERM’s explanatory gain is to connect defined state variables with several outcomes while preserving each mechanism, context and individual difference.
Compare the eight axes through shared measurements and studies
Demographic explanations in the same chain
Education, costs, contraception, values and low-fertility traps address different parts of reproduction. A person can wish for a child, postpone an attempt, face a practical barrier or need treatment. Recording one of these conditions as the explanation does not tell us what produced the other conditions or how they act together.
Under BERM’s premises, receiving biology feeds both motivation and reproductive capacity. Institutions and resources influence the opportunities to act; age and earlier experience shape the subsequent response. Demographic explanations become positions in this continuous process. A mechanism explaining one position does not thereby explain the origin or full size of the change.
This extends existing demographic frameworks at their interfaces. Bongaarts already distinguishes proximate biological and behavioural determinants from background conditions. BERM adds a state-dependent physical input and asks how its consequences are distributed across those determinants. Bongaarts 1978i; Bongaarts 2015i.
Process illustration · BERM’s conditional synthesis
A wish becomes a birth through several conditions
Receiving state enters two different branches: motivation and reproductive capacity. Practical opportunities and interventions enter at their own points in the process.
BERM’s conditional biological link
Field input → receiving state
Motivation
Relates to wanting a child and beginning an attempt.
Wanting a child
Reproductive capacity
Relates to establishing and sustaining a pregnancy.
Pregnancy and birth
Wanting a child
Experienced desire, expectation and goals.
Motivational state
Conditions and timing
Practical opportunities, demands and the chosen time.
Resources and policy
Attempt or treatment
Trying to conceive or undertaking fertility treatment.
Contraception and treatment
Pregnancy and birth
Conception, pregnancy progression and a live birth.
Biological capacity
Timing
Timing changes when an attempt takes place and how much reproductive time remains. It connects decisions with age-dependent biological conditions.
Changing one condition does not restore every condition in the chain.
Measured follow-up · the same individuals
Earlier expectations and later family size
Personal expected family size at about age 24 compared with the same person’s number of children at ages 41–50 in 2006. US NLSY79 follow-up; percentages weighted with 2006 sampling weights.
Women
Sample: n = 3 783
- Fewer than expected
- 34.9 %
- As many as expected
- 43.4 %
- More than expected
- 21.7 %
Men
Sample: n = 3 584
- Fewer than expected
- 42.8 %
- As many as expected
- 34.2 %
- More than expected
- 23.0 %
Expected family size includes children already born plus the additional children the person expected to have. Birth cohorts: 1957–1964.
An expectation alone does not determine the later outcome. This comparison does not identify how much of the difference reflects changing goals, practical constraints or biological capacity; it does not measure an EMF effect.
Morgan & Rackin 2010 · Table 2Ai23 explanations, four places in the chain
Choose a group, then open an explanation. The groups identify its main role; a factor can participate in several pathways.
What changes together?
- What the explanation captures
- Mortality and fertility changes form recognisable development trajectories. A transition describes their sequence; its name does not identify every causal pathway.
- What BERM derives
- BERM resolves modernisation into material inputs. Electrification changes the field environment alongside living conditions. The model’s biological branch reaches capacity and motivation through receiving state.
- Connection to the evidence
- In Belmin’s regional panel, electricity access remained associated with fertility alongside several development variables. This locates an association needing explanation; access does not itself measure the field. Belmin 2022i.
- What the explanation captures
- Education relates to family timing, resources, knowledge and employment opportunities. Years of schooling combine these different pathways into one measure.
- What BERM derives
- BERM separates education’s own effects from its changing environment. A qualification variable does not identify the local field, light history or biological reception. Its coefficient therefore does not finish allocating the mechanisms behind an association.
- Connection to the evidence
- Belmin considered women’s education alongside electrification. The earlier regression table shows reproducible estimates; education is not assigned a measured EMF dose. Belmin 2022i.
- What the explanation captures
- An urban environment combines housing, services, contacts and infrastructure. An urban category does not separate their effects.
- What BERM derives
- BERM resolves the category into inputs reaching the receiver and conditions for action. Housing cost affects practical opportunity; the model’s field branch affects receiving biology. One category can conceal both.
- What the explanation captures
- The economic model relates resources, costs and family preferences. Its original formulation also allows non-economic differences in preferences.
- What BERM derives
- BERM explains some of the model’s inputs: the origins of experienced reward and available capacity for action. The budget constraint remains real; changing it does not determine every other condition in the chain.
- Connection to the evidence
- The economic model need not imply that any sufficiently large payment eliminates every reproductive constraint. Becker 1960i.
- What the explanation captures
- Itao’s analysis finds two regularities linking birth rates and life expectancy. Its main λ measure is births per thousand person-years, not TFR.
- What BERM derives
- BERM treats the regularity as something a unifying explanation must account for. Longevity and the field environment belong to broader development, but similar curve shapes do not supply a biological transfer function between them.
- What the explanation captures
- Similar prosperity does not produce equal fertility everywhere. Country differences challenge a single aggregate variable’s universality.
- What BERM derives
- BERM uses a shared receiving structure while retaining differences in inputs, biological state, history and practical conditions. Parsimony means reusing a mechanism across conditions, not assigning every country the same coefficient.
- Connection to the evidence
- Cross-country heterogeneity also motivates Mahler and colleagues’ analysis. A community’s technology restrictions or high fertility do not alone measure its field exposure. Mahler, Tertilt & Yum 2025i.
- What the explanation captures
- Contraception directly changes pregnancy probability. Bongaarts’s framework distinguishes the proximate determinants of reproduction from their background causes.
- What BERM derives
- BERM additionally asks what produces the state guiding timing and contraceptive use. A method’s causal efficacy and the origin of its use are different explanatory tasks. Combined contraception also changes pharmacological receiving state: an SHBG change enters hormone availability and the conditions under which other inputs act. Panzer 2006i.
- Connection to the evidence
- Japan’s family-planning surveys document condoms and other methods in the 1950s. Availability of one particular method must therefore be distinguished from reproductive control as a whole. Bongaarts 1978i; Bongaarts 2015i; IPSS, Table 4–25i.
- What the explanation captures
- Autonomy changes how people can pursue their goals. Employment, childcare arrangements and desire for children are distinct variables.
- What BERM derives
- BERM retains real agency and places motivation within biological, learned and social history. Freedom to decide does not alone explain all initial conditions of a decision or establish biological impairment.
- Connection to the evidence
- Second-transition theory also addresses autonomy and values. Explaining their state-dependent formation is BERM’s additional task. Lesthaeghe 2010i.
- What the explanation captures
- SDT connects changing family forms with autonomy, values and institutions. Values affect action and change with experience.
- What BERM derives
- BERM extends the explanation behind an experienced value: receiving state, memories and social feedback shape what feels rewarding. Naming a value does not alone explain its formation.
- Connection to the evidence
- Lesthaeghe’s SDT synthesis and the earlier interpreter experiments concern different explanatory levels. A person’s hormonal or field state cannot be inferred from one expressed value. Lesthaeghe 2010i; Johansson 2005i.
- What the explanation captures
- Later births can reduce a particular year’s TFR without an equally large change in a cohort’s completed fertility. Later attempts also encounter biological ageing.
- What BERM derives
- BERM follows age, receiver history and remaining time for attempts together. Postponement can mediate an earlier change and amplify a later capacity constraint. Adjusting for it therefore changes the pathway being assessed.
- Connection to the evidence
- Tempo and quantum must be separated before interpreting fertility rates. Age is not converted into EMF-years without exposure histories. Bongaarts & Feeney 1998i.
- What the explanation captures
- The same person may have fewer, the same number or more children than previously expected. These differences can offset one another in an average.
- What BERM derives
- BERM separates receiving state, motivation, opportunity, timing and capacity. A continuing wish does not guarantee every later condition; later family size does not alone reveal which condition changed.
- Connection to the evidence
- The longitudinal figure compares the same people’s expectations and later fertility. Undershooting alone does not diagnose biological damage or an EMF effect. Morgan & Rackin 2010i.
- What the explanation captures
- Concern can be a real reason affecting a decision. A reported reason describes experienced meaning; it does not measure every process producing that experience.
- What BERM derives
- BERM derives experienced concern from the joint history of information, learning and receiving state. Identifying a felt reason leaves its formation to explain. The model does not require a moral explanation to be insincere.
- Connection to the evidence
- Interpreter experiments show in bounded tasks that a convincing explanation does not guarantee access to how a decision arose. They do not establish climate concern as the product of a particular hormonal change. Johansson 2005i.
- What the explanation captures
- Financial support changes costs, but its effect must be judged against what would have happened without it. A falling national trend alone does not establish ineffectiveness.
- What BERM derives
- BERM derives a chain constraint: removing a financial barrier does not itself restore biological capacity, motivation or lost time. Support can have an effect while the broader trend’s background condition persists.
- Connection to the evidence
- Quebec’s birth-subsidy programme has a positive effect estimate. It fits the same pathway map: the economic branch is causal but does not cover the entire process. Milligan 2005i.
- What the explanation captures
- Semen studies measure biological function separately from a reported wish for children. Concentration, total count and motility are distinct endpoints.
- What BERM derives
- BERM places them in the capacity branch: desire and attempts can remain while the conditions for fertilisation change. Cross-species comparison extends explanation beyond human institutions.
- Connection to the evidence
- Human, dog and horse trends appear above in their own units. They do not include simultaneous measurements of local EMF dose. Levine 2023i; Lea 2016i; Harris 2023i.
- What the explanation captures
- A chemical can change reproductive biology. External concentration, tissue dose and tissue response are separate parts of the chain.
- What BERM derives
- BERM places fields and chemicals within the same state-dependent reception. A chemical coefficient can then include an interaction. Decline in one legacy pollutant does not determine the history of every mixture or internal dose.
- Connection to the evidence
- The same chemicals have been studied in human and dog sperm; dogs are not treated as chemical-free controls. Field–metal experiments appear in the joint-exposure section. Sumner 2019i.
- What the explanation captures
- Treatment can enable a birth when pregnancy would not otherwise occur. Birth numbers and unassisted reproductive function are different measures.
- What BERM derives
- BERM places treatment in a compensatory pathway. The same endpoint can be reached with changed biological capacity and greater need for assistance. A preserved endpoint does not alone establish an unchanged chain.
- Connection to the evidence
- Smith’s registry study follows repeated IVF treatment cycles and live births. Uptake also depends on access and age, so an increase does not itself measure environmentally caused damage. Smith 2015i.
- What the explanation captures
- Reproductive-health measures, including semen changes and testicular-cancer incidence, can relate to shared environments. They remain distinct disorders and endpoints.
- What BERM derives
- BERM seeks pathways from a shared environment to receiving biology. Prosperity is not a tissue mechanism; naming oxidative stress also does not by itself derive a particular cancer.
- Connection to the evidence
- Aitken assembles environmental factors in reproductive health and explicitly includes electromagnetic radiation. The review does not supply an experiment establishing pocket-phone exposure as a cause of testicular cancer. Aitken 2024i.
- What the explanation captures
- Previous exposure can leave lasting biological changes. Individual memory, directly exposed generations and inheritance into an unexposed generation are different claims.
- What BERM derives
- BERM explicitly includes history in receiving state, allowing the present response to depend on earlier conditions. An inherited EMF effect additionally requires a mechanism connecting generations.
- Connection to the evidence
- History dependence in a current receiver does not alone establish an offspring effect. The earlier light–field experiments constrain state memory in their own systems. Hammad 2020i.
- What the explanation captures
- The trap hypothesis connects population structure, family ideals and economic expectations through feedback. Declining fertility changes the next generation’s environment.
- What BERM derives
- BERM adds the history of the receiver and encountered cues. Fewer births do not themselves remove the field input. If caregiving contacts also change, the model connects them to later receiving state and behaviour.
- Connection to the evidence
- Lutz, Skirbekk and Testa provide the demographic feedback structure. The complete infant-contact–oxytocin–human-fertility loop is a BERM composition. Lutz, Skirbekk & Testa 2006i.
- What the explanation captures
- A phone delivers content, changes contacts and produces optical and use-dependent RF exposure. A minute of use does not separate these inputs.
- What BERM derives
- BERM follows content, receiving state and physical input separately. One device can connect social feedback to the biological branch; attributing the whole association to screen time leaves this composition unresolved.
- Connection to the evidence
- Rahban’s use groups and Frei’s exposure comparisons appear earlier. Content does not determine equal transmission power: network connection, location and use pattern affect exposure. Rahban 2023i; Frei 2010i.
- What the explanation captures
- Relaxing a birth limit changes permission to realise a wish. Earlier policy has already affected age structure, families and timing.
- What BERM derives
- Under BERM’s premises, removing a prohibition does not reset receiver history, biological capacity or environmental input. An immediate response and sustained recovery are therefore distinct outcomes needing separate explanations.
- What the explanation captures
- Family ideals arise from experiences, norms and perceived possible futures. A changing ideal can cause later action and result from earlier experience.
- What BERM derives
- BERM closes the feedback through time: encountered families and caregiving contacts shape later receiving state, while repeated decisions change subsequent contacts. A norm then also stores biologically realised feedback.
- Connection to the evidence
- The trap hypothesis addresses feedback in family ideals; longitudinal observation separates earlier expectations from later family size. Neither assigns a fixed hormonal profile to an individual ideal. Lutz, Skirbekk & Testa 2006i; Morgan & Rackin 2010i.
How the demographic sources were integrated
Aitken’s 2024 review explicitly includes electromagnetic radiation among environmental factors. Its R² = 0.775 concerns contraceptive use and TFR across countries in 2000–2001. It is an aggregate association, not an EMF coefficient. Aitken 2024, Figure 5i.
Itao’s published two-pathway analysis uses crude birth rates as its main outcome. Its 237-country dataset does not establish an EMF dose threshold or turn life expectancy into a tissue-response parameter. Itao 2026i.
The page retains its four masking levels. Unequal measurement and attribution across research traditions belong to epistemic masking; sensory masking remains the receiver level. The groups below are reading categories, not a new hierarchy of evidence.
Why several partial explanations can share one missing condition
If the same receiving state changes both what feels worth pursuing and the probability of achieving it, the resulting observations can be recorded as separate changes in values, timing, family size and treatment use. In BERM these are different outputs of a connected system. Removing one financial or legal constraint does not, by itself, reset that system’s remaining conditions.
Why the shared causal structure explains more
Within BERM’s premises, the field-and-receiver account explains more than a single proxy because it connects the origin of the change to its later consequences across biological levels. Parsimony comes from reusing the same specified processes: each observed endpoint does not require an independent starting explanation.
Causal illustration
From separate explanations to a shared structure
Compare the same observation levels in two views. BERM connects them through defined component mechanisms, while each level retains its own measurements.
Five observation levels are displayed separately, each with its own proxy or observation. This view leaves their relationships open.
Physical environment
Local fields, their timing and physical structure.
Proxy or observation
Technology use or electricity use
Receiving biology
State, timing, availability and prior exposure.
Proxy or observation
A clock-phase or protein measurement
Hormonal or sensory process
Signal reception and the resulting functional response.
Proxy or observation
Hormone concentration or sensory performance
Behaviour
Eating, movement, caregiving or a reported choice.
Proxy or observation
Diet, exercise or reported reasons
Population or ecological community
Outcomes accumulated across individuals and time.
Proxy or observation
Birth rates, abundance or community composition
Each proximate explanation covers its own stage. Their separation leaves the causes of their changes and the connections between levels unresolved.
Parsimony here means reusing specified component mechanisms, not fitting every outcome with one free coefficient.
Four distinct categories remain: Lindgren-derived geometry; imported empirical biology; BERM’s conditional mechanisms; and open calibration gaps. Lindgren’s geometric result does not itself derive a biological response.
Seven biological systems, seven explanatory paths
A person’s decision about contraception, education or family formation is not a reproductive mechanism of the other six species. Material exposures cross that boundary: the selected studies include non-optical fields, light and chemicals. BERM connects such inputs to the organism’s state within one conditional framework.
| System / outcome | RF / low-frequency fields | Optical light | Chemicals | Climate / habitat | Food / activity | Personal family decisions | BERM composition |
|---|---|---|---|---|---|---|---|
| HumanSperm, circadian response; decisions contribute to birth rates.De Iuliis 2009i; Chang 2015i; Sumner 2019i | ● | ● | ● | — | — | M | M |
| DogChemical DNA response; no significant semen change in the phone protocol.Sumner 2019i; Dong 2022i | ○ | — | ● | — | — | × | M |
| HorseRF + contact electrodes preserved DNA and acrosomes; motility did not improve.Berlinguer 2017i | ● | — | — | — | — | × | M |
| RobinMagnetic orientation under radio-frequency noise.Engels 2014i | ● | — | — | — | — | × | M |
| HoneybeeFlower landing under manipulated electric fields.Mallinson 2025i | ● | — | — | — | — | × | M |
| Clawed frogReproductive development under atrazine exposure.Hayes 2010i | — | — | ● | — | — | × | M |
| CoralSpawning dates associated with artificial night light.Davies 2023i | — | ◇ | — | — | — | × | M |
- Experiment: the specified intervention altered the named response
- Tested: no significant change under this protocol
- Association: exposure and outcome were observed together
- Model: a proposed explanatory connection
- Outside scope: the organism’s own human family decision
- Not examined by the studies selected here
A blank evidence cell does not mean no effect. Experimental cells concern the named outcome, not an entire population decline. Climate, food and chemicals remain material explanations across species; BERM’s common structure does not by itself rank their empirical contributions.
Across species
The electromagnetic environment is part of the material conditions of humans, laboratory animals, birds and insects. Human family-planning institutions alone do not cover that whole scope. Species comparisons motivate looking for shared material routes; chemical exposure, light, temperature and habitat can also cross species boundaries. Klimentidis 2010i; Engels 2014i.
Across biological levels
BERM links a molecular or sensory response to hormonal regulation and behaviour through receiving state. Appetite and food intake then become consecutive parts of an explanation. Sensory and pharmacological interventions constrain particular links in this structure. Marlin 2015i; Hinkle 1987i.
Across different conditions
Light history, reproductive phase and receptor state provide named reasons for differences in a response. Reusing these specified conditions is more informative than adding a separate unexplained exception for each observation. Hammad 2020i; Reyes-Guerrero 2010i.
Across measurement levels
A community label, a report of exercise and a daily step count can describe different parts of the same material setting. BERM asks which process each measure captures, and then connects exposure, response and recorded outcome. Katz 2012i; Stein 2016i.
From individual responses to population outcomes
In BERM’s chain, a biological shift changes the distribution of responses across individuals. Birth counts accumulate through partnership, attempts at conception, conception probabilities and pregnancy outcomes within age groups and time intervals. Ecological outcomes likewise combine individual foraging, survival and reproduction. These are the explicit steps between receiving state and population measure.
What makes the explanation better?
The advantage is the coverage of the causal structure: BERM explains why proximate causes change, how they interact and how their effects accumulate across levels. A model ending at income, food intake or a diagnostic label leaves these connections outside its explanation. This is a conclusion about the explanatory structure under the stated premises; the empirical strength of each link is assessed from its own evidence.
The shared structure retains the distinct doses and receiving mechanisms of optical, ELF, IF and RF exposures. Explanatory economy comes from reusing those defined mechanisms and aggregation rules across observations.
How BERM joins the evidence
The contribution of proxy masking is to keep the full chain in view. BERM supplies an explicit physical starting point and a conditional receiving operator. Studies from different fields supply biological components and observed outcomes.
- Lindgren-derived geometry
- The 2025 formulation specifies a tensor change when a background and an external contribution are combined. It retains their cross terms before any biological response is assigned.
- Imported empirical biology
- Sensory, pharmacological and ecological experiments constrain particular receivers, internal doses, timing relations and functional outcomes in their own systems.
- BERM’s conditional mechanism
- A state-dependent receiving operator connects the geometric input to named biological changes. The model then composes those changes through behaviour, interactions and recorded outcomes.
- Open calibration
- The physical scale, gauge prescription, tissue response, sign, delay and human outcome calibration have to be specified. A component study does not by itself determine the complete historical contribution.
Open the mathematical connection
With the BERM scale κ, Lindgren’s 2025 ansatz and the split A = A₀ + a give the following exact tensor expansion. This is the geometric step. Lindgren 2025i.
The biological step additionally assumes a named matter–metric coupling and a causal response operator. Its receiving state includes light history L, chemical state M, pharmacological intervention D and other physiological or learning history H.
The operator’s kernel, scale and tissue-specific parameters remain explicit model assumptions. Optical and RF oscillations need not retain a direct time-averaged cross term for light to alter a later response through the receiving state. FieldState may supply observations or estimates of the physical input; the explanatory operator belongs to BERM.
Read the full tensor derivationThe unifying idea is that a measured chemical, a behaviour or a lifestyle category can explain a result while leaving an earlier condition unnamed. Following the signal, the receiver and the observed endpoint separately makes those conditions visible in the model.
How to read the figures
The causal diagram and response curves explain specified mechanisms using illustrative values. They are not measured exposure histories or fitted human dose–response curves. The Amish activity figure uses published group measurements, with different units shown in separate panels. Original studies are linked beside the relevant claim.