Luys — Neurofisiologia e Fisiologia della Fascinazione/en

This page documents the neurophysiological observations of Prof. Jules Bernard Luys on fascination and hypnotism, drawn mainly from the Leçons cliniques (1890). Luys writes directly inspired by the results of Donato — he explicitly cites him as the one who brought fascination to the attention of modern science.

Source: Leçons cliniques sur les principaux phénomènes de l'hypnotisme — ISI-CNV Drive

Luys' Neurophysiological Model

Luys builds a precise explanatory system based on three fundamental principles derived from the observations of Brown-Séquard:

1. Inhibition and Dynamogeny

The phenomena of hypnotism and fascination are not mysterious but reducible to two ordinary physiological laws:

Inhibition: some brain regions are turned off — consciousness, will, cutaneous sensitivity
Dynamogeny: other regions are simultaneously enhanced — muscular strength, optical sensitivity, emotional regions

Luys: «These phenomena of hypnotism... were, for the most part, only the generalized and amplified expression of these phenomena of inhibition and dynamogeny with which the works of Brown-Séquard have enriched contemporary science.»

2. The Transformation of Nervous Forces

The key phenomenon: when cutaneous sensitivity disappears during fascination/léthargie, the same nervous energy **does not disappear but transforms and concentrates elsewhere**:

Cutaneous sensitivity disappears → muscular strength increases up to **doubling** (10-12 kg → 20-25 kg on the dynamometer)
Cutaneous anesthesia appears → optical sensitivity is enhanced to the point of perceiving light through an opaque screen of 5mm
Consciousness shuts down → emotional regions ignite with extra-physiological intensity

Luys calls this «déséquilibration des courants nerveux» — the destabilization of nervous currents: rarefied in one point, they accumulate in another, acquiring extra-physiological energies.

3. The Seriation of Hypnotic States

Luys proposes a visual scheme — the «puits» (well) — to explain the progression of states:

Depth	State	Character	Consciousness
Surface	Fascination (Brémaud/Donato)	Anesthesia + catalepsy + suggestibility	Partially present
Intermediate	Catalepsy	Muscles malleable like wax, eyes open, anesthesia	Absent
Deep	Somnambulism	Speaks, responds, but unconscious	Apparent but fictitious
Maximum	Léthargie	Coma, maximum anesthesia, maximum muscular strength	Completely absent
Ultra	Ultra-léthargie	Vital risk — pulse almost imperceptible	—

Donato's fascination corresponds to the superficial levels — it is the **petit hypnotisme** — but with repeated sessions, fascinated subjects progressively descend towards the deeper layers.

Key Experimental Discoveries

Doubled Muscular Strength in Léthargie

Luys systematically measures with the dynamometer before and during fascination:

«In a normal subject, forearm deflection requires a traction of 10-12 kg. In the state of léthargic contracture, 20-25 kg are needed — and at this point, the muscle does not deflect, the entire body is dragged along with it.»

This is an **objective and non-simulable** datum — the dynamometric measurement. The subjects Théo, Esther, Clarisse (three reference subjects in the Leçons) all show the same phenomenon.

Optical Hyperesthesia: Seeing Through Obstacles

In the state of léthargie, with eyes closed:

A blue glass ball placed in front of the face (with a 5mm wooden screen interposed) produces an **intense repulsion reaction**
A yellow ball produces a **reaction of joy and irresistible attraction** — proportional to the size of the ball
A red ball has an almost neutral effect

Luys: «Sensitivity has become so concentrated in the expansion of the optic nerve, that with eyes closed, if I place a carafe stopper in front of him, interposing a 9mm black wooden screen, the subject will feel the luminous vibrations!»

This is the foundation of his research on the «action at a distance of medicinal substances» — the controversial subsequent discovery.

Dédoublement: The Two Halves of the Brain

Luys demonstrates that the two hemispheres can be placed in different states **simultaneously**:

Raising the **right** eyelid of a subject in léthargie → only the **left** lobe lights up → **left hemi-catalepsy** while léthargie remains on the right.

The arm corresponding to the cataleptic side remains in the imposed position; the arm corresponding to the lethargic side falls inert.

Conclusion: «The individual is thus experimentally split into two distinct psychological individualities.»

Experimentally Induced Emotions

The emotional regions in fascination/catalepsy acquire extreme sensitivity:

Blue ball → repulsion, expression of disgust
Yellow ball → joy, ecstasy, irresistible attraction
Red ball → almost neutral (but Esther shows repulsion even at rest — she chooses not to wear red in normal life)

Luys: «The emotional regions of the brain can, at the hypnotizer's will, be individually awakened with their most varied modalities.»

The Automatic Contracture

A simple touch to the skin of the forearm in the léthargic state provokes **immediate contracture** of the entire muscular system of the limb. The same touch to the antagonist muscles (extensors) instantly cancels it.

Luys notes: these are «phénomènes d'hyperexcitabilité neuro-musculaire» — phenomena of neuro-muscular hyperexcitability. The physiopathological mechanism is still obscure to the science of the time, but the reproducibility is total.

The Explicit Connection with Donato

Luys does not hide the source of inspiration. In the Leçons, mentioning fascination as a form of «petit hypnotisme»:

«To the phenomena of petit hypnotisme, I will attach the examination of those curious manifestations to which Dr. Brémaud, naval physician, has so rightly called the attention of doctors in recent times, and which he described under the name of fascinations.»

And in the Revue d'Hypnologie, after describing the rotating mirror:

«It is curious to note from the point of view of the history of science, that this state of fascination which we readily consider as a novelty, is on the contrary known for a long time and daily used by magnetizers in public hypnotism sessions. The subjects they exhibit in public are, most of the time, merely fascinated subjects.»

The «magnetizer» to whom he refers is Donato — and Luys knows it well, given that the Salpêtrière and the Charité awaited his visits to Paris.

The Réveil Process — Controlled Awakening

Luys teaches that awakening is **the most delicate operation**. An incomplete awakening leaves the subject in a state of «demi-obscurité»: they walk, talk, act — but are not fully conscious. In this state:

They can steal in a shop without knowing it
They can commit indecent acts publicly
They can sign documents without understanding them

The safe awakening protocol:

Blow lightly on the eyes (quick but abrupt method)
Verbal suggestion: «You will wake up in one minute» (preferred physiological method)
Verification: «Where are you? Who am I?» — if they answer correctly, they are fully awake

- Fundamental protective measure:** before taking leave, give the suggestion that the fascinable subject «will not allow themselves to be hypnotized by anyone, except by you or another doctor designated by you». It is «a truly philanthropic measure».

Fascination and Statistical Data

Luys conducts one of the first statistical analyses on fascinability:

Out of **31 nurses** (18-30 years): **14 fascinable** with only the shiny object; of these 14, **5 reach grand hypnotisme** after 3-4 sessions
Out of **32 males** in his service: **11 fascinable** (~34%) — all pathological cases (epileptics, morphine addicts, paralytics)
Maximum fascinability: **18-30 years**
Fascinable over 55 years: yes, with pathologies (ataxic paraplegics, hemiplegics)

Luys' conclusion: fascinability is much more widespread than believed, and depends on latent aptitudes unknown to the subjects themselves.

Sources

Correspondence with the Polyvagal Theory

Luys' fascination/catalepsy/somnambulism/léthargie/ultra-léthargie scheme corresponds with extraordinary precision to the hierarchy of the autonomic nervous system described by Stephen Porges in the Polyvagal Theory (1994-2011). Léthargie corresponds to the activation of the dorsal vagal system (immobilization), fascination to the transition zone between the ventral and dorsal systems. See the dedicated article: La Scala di Luys e la Teoria Polivagale di Porges.