Rivista del mese

Proposta per la creazione di una scala del dolore su parametri psicofisiologici

Autore
Dr. Filippo Parodi
Specialista in Anestesia e Rianimazione, Terapia del dolore FMH, Terapia Antalgica, Ematologia, Pneumologia.
Membro SSIPM con certificazione RME 142 è consulente, presso l’Ospedale Regionale di Lugano, della Terapia del dolore neuromuscolare.

 



Abstract

La conduttanza è l’inverso della resistenza elettrica del corpo umano varia da un individuo all’altro, questa variazione deriva sostanzialmente dallo stato di umidità della pelle stessa dovuto all’azione delle ghiandole sudoripare sottostanti.

Il valore assoluto della resistenza cutanea è un indice dello stato generale di attivazione del sistema nervoso dell’organismo e è indicato come attività tonica. Il valore tonico è maggiore (quindi la conduttanza è minore) se una persona è in uno stato di rilassamento mentre è più basso (conduttanza più alta) quando un individuo è agitato o nervoso in quanto aumenta la sudorazione cutanea.

Le rapide risposte a stimoli emozionali, dolorosi che siano sensoriali o dovute a immaginazione (definiti attività fasica) portano ad aumento della conduttanza.

In numerosi studi di ricerca si comincia a studiare con attenzione la correlazione della conduttanza cutanea con i parametri di stress cronico ma anche come possibile marker del dolore.

Per esempio, in un articolo apparso su Repubblica si evidenzia come la conduttanza sia collegata allo stato di stress sul lavoro.

Nel libro del Dott. Boschin la conduttanza è utilizzata come marker per individuare risposte a stimoli emozionali.

Il software, attraverso un dispositivo che si collega semplicemente ai sensori, permette di misurare le differenze di conduttanza in momenti diversi e di confrontarli.

Con il software è anche possibile confrontare le variazioni di conduttanza con altri parametri come ECG ed EMG al fine di avere una misura maggiormente precisa dello stato dell’individuo in quel momento o per confrontare periodi differenti,
La conduttanza cutanea in diversi ambiti è utilizzata da professionisti, la misura della conduttanza può essere così utilizzata per avere un maker, per esempio per i seguenti stati:
• Stress
• Emozione in risposta a stimolo
• Paura
• Dolore
• Stanchezza
• Sovrallenamento
• Stress o dolore cronico

Il valore rilevato viene espresso numericamente dopo opportuna e valida acquisizione, con possibilità grafiche del grezzo di monitoraggio dei valori min e MAX e riportato in memoria comparativa, con la possibilità di confronto con altri test e ne traduce l’importanza clinica. Si pensi al paziente che non è in grado o non può comunicare, sottoposto a terapie analgo-disforiche e a procedure di analgesia da hospital (partoanalgesia).

Dallo studio sono emerse le seguenti conclusioni della tesi che hanno dato poi avvio al primo studio per la creazione di una scala  riportata nel lavoro.

“In considerazione della nuova tecnologia che permette una indagine strumentale di parametri considerati solo in laboratorio di fisiologia con strumentazioni inavvicinabili come prezzo e valore, questo monitoraggio in una fase clinica iniziale, in una limitata attività di laboratorio, con necessità di risposte concrete terapeutiche ,soffre della validazione e significatività dei grandi numeri ma ,nonostante questa lacuna in ambiti per ora specialistici, la sua applicazione porta conoscenza e dati soggettivi  ma quantificabili oggettivamente sul singolo paziente, permettendo di individuare i problemi meno amplificati di difficile conoscenza anche a carico del soggetto stesso in trattamento.

L’ applicazione senza monitoraggio, attualmente è eseguita a random con consenso alla prima seduta di consulenza del paziente. Nonostante il limite di mancanza di un vero protocollo (monitoraggio eseguito non da medico, ma da personale sanitario senza conoscere il motivo clinico della patologia del paziente) la rilevazione può portare random dei dati importanti a fini conoscitivi e per le situazioni cliniche.


Foreword

The attempt of the present work is to demonstrate objectively the real subjective effectiveness of information therapies in the treatment of algogenic pathologies.

To this end, thanks to the joint collaborative efforts with the company Proereal through the use of the AZ Bioprocess solution, with constant commitment, methods and observations were addressed to build a unit of measurement of pain derived from electrical parameters in humans and animal species.

Thanking all the students and the school director Prof. Militante of the IIS Lagrange of Milan who participated in thisproject.

At the national level, importance is given to the issue of pain: The legislation published in the Official Gazette of the Italian Republic – General Series – n. 149 of 29-06-2000, agreement between the Ministry of Health, the Regions and the autonomous provinces, indicates the guidelines for the construction of the Painless Hospital.

The guidelines are intended to introduce actions in order to monitor the level of pain and find ways to alleviate the suffering caused by the ongoing disease, in particular oncological pathologies.

Recall that according to the World Health Organization (WHO), “health is a state of complete physical, mental and social well-being and not the simple absence of the state of illness or infirmity”.

The International Association for the Study of Pain (IASP) gives a definition of pain: “an unpleasant sensory and emotional experience, associated with actual or potential tissue damage or otherwise described as such. Pain is always a subjective experience. Each individual learns the meaning of that word through experiences related to an injury during the first years of life. Surely it is accompanied by a somatic component, but it also has an unpleasant character and, therefore, an emotional charge”.

Another way to define pain is the following “pain is a sensory perception caused by stimulations of various kinds, able to stimulate specific receptors, called nociceptors”.

Nociceptors are anatomical structures made up of groups of nerve cells (sensory neurons) from which fibers afferent first to the spinal cord and then to the sensory areas of the brain depart. The word “nociception” indicates those mechanisms of transmission of painful stimulations, which always have a peripheral origin deriving precisely from the localization of pain receptors.

Two components linked, connected and interconnected to pain are highlighted, the emotional state and the mechanical biochemical state.

So we asked ourselves the following question: in addition to measuring pain with subjective method through the current scales, is it possible to give indications on pain also with instrumental measures?

On Micropedia you can find some interesting reflections that we report here:

“Although it is always and in any case an expression of pathologies of various kinds, pain is characterized by its physiology, as its manifestation follows a well-defined path both from an anatomical and functional point of view.

It is in fact a phenomenon absolutely compatible with certain conditions that, although very unpleasant or even intolerable, are part of existence.

The term nociception is intended to indicate the set of mechanisms of transmission of painful stimulations from the periphery to the central nervous system, as pain always presents a centripetal direction.

It is on the interaction of the different brain areas that the processing of the nociceptive signal and its consequent awareness depends.

Pain is usually accompanied by more or less intense defense reactions and consciousness contents related to emotional and anxious experiences.

It is always an unpleasant experience deriving from an evident fusion between body (primary seat of algic stimulation) and mind (responsible for perception), so much so that in many cases we talk about psycho-somatic genesis of pain” (“taken from © 2020 Micropedia All Rights Reserved”)

Today the most widespread method for the evaluation of pain is “the visual analog scale (VAS) which uses a segment ten centimeters long, where each interval corresponds to a progressively greater degree of painful perception, always evaluated from zero to ten.

Through this support, the patient must indicate a point of the segment corresponding to his pain, the advantage is related to the high sensitivity and reliability, the disadvantage is related to the impossibility of being used by disabled patients (visual, physical or cognitive disorders) or who are in an advanced stage of the disease.”

Alongside the traditionally used scales, the possibility of proposing in the field of monitoring, the use of an additional method especially in situations of dubious response to therapies against musculoskeletal pain and sensory somato, even in the animal world before and after bioenergetic applications (drugs, manual and instrumental techniques, acupuncture, phytotherapy and Pacth) to test the validity of the numerous devices in the literature and support the  conventional SUBJECTIVE scales, without objective feedback, such as V.A.S . N.R.S. which, although useful in a statistical mass evaluation, are of limited use in the field of evaluation in integrated medicine.

This takes into account the detection of psychophysiological parameters such as skin conductance (1), heart  rate (2), activation of brain waves (3).

The monitoring is conducted through an electronic board that processes algorithms, connected via Bluetooth to a dedicated App available for any operator. Initially, the software was designed for applications on athletes at a high competitive level to improve the state of well-being and their state of performance, objectifying the state of health, the response to training cycles and to improve overall athletic performance.

In this first study,   the responses to a painful stimulus given by the conductance parameter were consideredabove all. Starting  from the work carried out in the thesis  developed at the UNIVERSITY OF EASTERN PIEDMONT, DEPARTMENT OF TRANSLATIONAL MEDICINE entitled OBJECTIVE INFORMATIONAL BIOELECTRIC PROFILES PRELIMINARY DATA, where clinical cases were studied and in consideration of the possibilities of application of monitoring techniques, measurements were carried out in conditions of absolute freedom from NRS 0 algic symptoms in patients homogeneous by age  registry (less than 65 years, over 16 years) with prevalence of the female sex, without therapeutic interference of any kind, which led to support a remarkable uniformity of data in these subjects.

Practically the two most practical and coincident monitorings that can be performed in any health study and by other colleagues involved, are to be referred to EDA skin conductivity and ECG monitoring as an index of stress and standard deviation, PNN50 the responses detected with EEG were difficult to monitor due to the emotionality of the PZ as a baseline state in clinical practice sessions,  as well as the electromyographic recording presented enormous variations in relation to the type of patient, sedentary or sports and with consequent difficulty of application in muscle sectors (tested the joint tendon dominant forearm).

The cases briefly examined by Dr.Parodi, in the aforementioned thesis,  which can be considered significant, are represented by patients commonly afferent in the Pain Clinic clinic, suffering from acute low back pain in evolution, LOW BACK PAIN subacute on a chronic basis, CPRS 1 chronicized, CPRS2 Subacute post herpetic neuropathy, initial fibromyalgia patient treatment with GAET (4) and application modulatory frequency of Fibonacci.

For the parameter CONDUCTANCE for skin comfort (EDA) it is possible to measure the change in the electrical resistance of the skin, with analysis of the average of the last 250ms values in microsiemens. This parameter provides valuable information on the degree of pain, on the type of the same, somatiform or peripheral, and  allows an effective multiparametric analysis on the type of stress of the subject and on the emotional involvement and reliability of self-assessment.

The Galvanic Response of the Skin (GSR), Electrodermal Activity (EDA) and Skin Conductance (SC), are names to indicate the measurement of changes in the electrical characteristics of the skin.

The conductance is the inverse of the electrical resistance of the human body varies from one individual toanother, qthis variation derives substantially from the state of humidity of the skin itself due to the action of the underlying sweat glands.

The absolute value of skin resistance is an index of the general state of activation of the nervous system of the organism and is referred to as tonic activity. The tonic value is higher (so the conductance is less) if a person is in a state of relaxation while it is lower (higher conductance) when an individual is agitated or nervous as it increases skin sweating.

Rapid responses to emotional stimuli, painful whether sensory or due to imagination (called phasic activity) lead to increased conductance.

In numerous research studies we begin to carefully study the correlation of skin conductance with the parameters of chronic stress but also as a possible marker of pain.

Forexample,  in an article published in Repubblica (link in the final bibliography)it is highlighted how conductance is linked to the state of stress at work. In Dr. Boschin’s book, conductance is used as a marker to identify responses to emotional stimuli.

TheAZ Bioprocess software through a device that simply connects to the sensors allows you to measure the differences in conductance at different times and to compare them.

With the AZ Bioprocess software it is also possible to compare the changes in conductance with other parameters such as ECG and EMG in order to have a more precise measurement of the state of the individual at that time or to compare different periods, Skin conductance in different areas is used by professionals, the conductance measurement can thus be used to have a marker for example for the following states: • Stress• Emotion in response to stimulus• Fear• Pain• Fatigue• Overtraining• Stress or chronic pain

The detected value is expressed numerically after appropriate and valid acquisition, with graphic possibilities of the monitoring raw of the min and MAX values and reported in comparative memory with the possibility of comparison with other tests and translates its clinical importance. Think of the patient who is unable or unable to communicate, undergoing dysphoric analgus therapies and hospital analgesia procedures (partoanalgesia).

From the study emerged the following conclusions of the thesis that then started the first study for the creation of a scale and here we report

“In consideration of the new technology that allows an instrumental investigation of parameters considered only in the laboratory of physiology with unapproachable instruments such as price and value, this monitoring in an initial clinical phase, in a limited laboratory activity, with the need for concrete therapeutic responses, suffers from the validation and significance of large numbers but, despite this gap in areas for now specialized,  its application brings knowledge and subjective but objectively quantifiable data on the individual patient, allowing to identify the less amplified problems of difficult knowledge even at the expense of the subject himself in treatment.

The application without monitoring, is currently performed at random with consent to the first consultation session ofthe paziente. Despite the limitation of lack of a real protocol (monitoring performed not by a doctor, but by health personnel without knowing the clinical reason for the patient’s pathology) the detection can randomly bring important data for cognitive purposes and for clinical situations.

A 40-year-old patient with multiple sclerosis sent for balance disorders and extreme asthenia, at pre-consultation monitoring unexpectedly presented an average EDA of 4.6; in consideration of the data we asked ourselves the question of why the problem was not declared, it was obtained by response to a now chronic, little considered, bilateral lumbar pain probably dueto  the suspension of drugs.

Another Pz during informational therapy for a migraine situation rebellious to drug treatment, during the control doubled EDA from 2.1 to 4.6 because the visiting health care provider had only touched a DIM C4 DX, which would have remained silent and untreated.

Pz of 60 years male, post symptomatology of parainfluenza angina, after performing cervical massages in another location, with ENT control was practiced ear wash accused a very acute pain at the limit of fainting with immediate clinical control totally negative by the ENT specialist. This symptomatology persisting during the positions of increased pressure (Valsava) increased in intensity and was relieved only by the compression of the left ear. The physical examination was decisive for an area of hypoesthesia at the pressure of the left auditory meatus with an area of hypoanalgesia to the face and left periorbital. Routine EDA monitoring showed a figure of 6. 5 average on the bed, with the maneuvers of bending the trunk and cough explosion the data reached the limits of scale. The monitoring for this type of pain certainly neuropathic convinced the wife of the real serious problem of the husband and not of the usual manifestations slatentized by low threshold, because the patient had carried out multi-specialist visits judged negative. In consideration of the pathology, the neuroradiologist was contacted to focus attention on invasive pathologies affecting the acoustic and vestibular nerve with the suspicion of neurinoma, using a dedicated MRI package.

Monitoring, even if in the criticality of data not present in the specific literature, offers important food for thought. It is of valid help in distinguishing the mixture of pain from the nociceptive component from the neuropathic one. In the neuropathic component, the baseline values of EDA are always much higher than threshold 4 compared to nociceptive pain of usually skeletal muscle origin. The chronic component, compared to the acute one, is highlighted by a stress index not very far from the average of normality with considerable “imbalance” in the PN50 and prevalence of orthosympathetic tone. The temporal duration belatedly influences the homeostatic response to pain, as if acute nociceptive pain were subjected to an attempt at control and the subsequent failure allowed, after a subjective temporal variation in considering the problem centrally, the organism to direct resources in other areas against the triggering cause in a defensive way.

It would be interesting to see if retrospective studies could help identify algic behavior and painful thresholds in our ancestors and primitive populations that exist today. Not wanting to deliberately enter into the psychosomatic component of pain (typical in cancer patients) it can be said that a method made executable in the laboratory, albeit with the current criticality of the lack of real randomized protocols, in double blind, with specialists in informational therapy and guidance and help in customizing the real needs of the patient, allows a more effective therapy that can be monitored over time. Using a bioelectric monitoring of pain means approaching a completely complex world of a genetic and neurophysiological nature. Approaching real life, the triggering gestures, sometimes clinically incomprehensible of the subject as they can be dynamically performed in the most varied conditions of pathology, does not correspond to the personal reality that is sometimes unconfessable.

The initial purpose of the work was to combine the numerous scales of pain proposed with an objective tool that, although within the limits of standardization (anecoic chamber, external temperature, environmental situation, posture, emotionality, hormonal profiles,) can represent a valid help for the therapist of disciplines that at the present time are still little validated, as the multidisciplinarity in the algological field follows paths that are difficult to support:  algologist, physiatrist, neurologist, acupuncturist, medical physicist.

The various figures could intervene rightly with truly effective therapies on the subject, decreasing the arrogance of those who with their own knowledge solve all situations in the light of objective data in the sole interest of the Patient, with a single instrumental language.  Monitoring could still have a value in the insurance field of conflicting medicine as it could support or refute clinical situations of compensation or work activity in non-permissive conditions, with detection on the claims of patients.

The purpose of this short pilot study is to intrigue and make known to various professionals a new way of dealing with problems and allow to combine traditional methods with other disciplines always with objective demonstration finally univocal of what the patient says, creating a uniform basic dossier of the experience allowing the various professional figures the most appropriate therapy and avoid momentary psychological effects and economic burdens by bringing back  the Pz to total autonomy or to the best possible well-being.

Bioelectric monitoring, however, allows a professional critical evaluation of devices increasingly present on the market with therapeutic purposes, moreover, a particularity always underestimated, it offers the opportunity to identify any actors that revolve around the subject, modifying therapeutic attentions. In the hope that new bioelectrical monitoring will be codified and implemented in the medical field, by all the actors of the welfare and health professions to help and share the needs of people’s well-being as INDIVIDUALS and not representative of pathological noxes by guidelines, in the algological field validated without objective NUMERICAL data but statistical study.

In the light of the considerations of the work done by dr. Parodi was tested on 120 boys and 20 staff at a high school in Milan. The test was carried out by monitoring people through EDA and ECG for 120 seconds in a state of tranquility with their hands resting on a table, then a stimulus was administered with an aneroid pressure cuff device for a maximum of 30 mmHG more from the first perception of the state of discomfort.

The electrodes were placed for EDA monitoring on the first and third phalanx of the middle finger of the right hand.

The AZ Bioprocess solution supplied  by Proereal was usedto carry out the tests.

AZ Bioprocess is a solution to detect and interpret physiological parameters through the processing of biometric signals from biomedical sensors; it is addressed to doctors, physiotherapists, psychologists, sports operators, performance centers and sportsmen.

AZ Bioprocess is not a diagnostic solution, it is a solution for the analysis of biometric data that helps professionals and operators to interpret data through accurate surveys and analyzes with a clear extrapolation of the results. Today, technology offers us numerous opportunities to improve our well-being and our state of health and also gives us the possibility to remotely monitor the physiological parameters of the person not only with the aim of treating but also to improve the physical and mental condition for healthy people.

 

The solution consists of 3 components that offer multiple possibilities for measuring parameters, ensuring the reliability of the data and ease of use.

  • The controller is an electronic device installed in a lightweight and small sleek case that can be placed very easily . The device contains a series of sensors that transform the received signals into electronic data.  The device sends the data via bluetooth to a tablet/pc.
  • The solution involvesthe use of electrodes to be placed in contact with the body for the detection of biometric data. The electrodes  are  supplied together with bands to be easily positioned. For extreme cases it is also possible to use adhesive electrodes.
  • The software installed on a tablet constitutes the intelligence of the system, wirelessly manages the controller and analyzes the data coming from the sensors, providing important parameters to evaluate the psychophysical state of a

The app provides an export that allows,once the tests have been carried out,to process them also with externaltools. In addition to the instrumental evaluation, a subjective evaluation was also requested from the user who was administered the test.

The subjective rating on a scale of 1 to 10 for all the people tested was a nuisance always between 1  and 4. No one ever indicated a value above 4,and  the  average  was  1.72.

The tests were carried out by non-medical personnel and then analyzed by a team of engineers who considered only 55 tests valid.

Conductance has a different base value per person. It is therefore not possible to statistically compare the absolute value. A scale was created with a mathematical algorithm that takes the values of conductance during testing, this scale returns a value in percentage and was called the Lagrange scale.

Of the 55 tests considered valid, a Lagrange scale value of between 5% and 40 % was obtained, which matches and aligns with the values expressed by the SEA.

The results obtained were as follows:

Initial mediated value Lagrange scale value
2.03 5.86
3.66 6.20
2.93 6.61
1.07 7.14
3.07 7.22
7.97 8.13
1.50 8.17
0.99 8.55
0.89 9.60
3.08 9.69
2.02 10.07
1.51 10.43
1.07 11.39
3.30 11.71
4.97 13.40
3.95 13.84
1.20 14.27
1.34 14.60
1.33 15.33
1.07 15.41
0.86 16.42
1.32 17.36
0.95 17.94
0.95 17.95
0.14 18.27
2.92 19.75
4.61 20.69
2.78 21.15
0.80 21.25
3.91 22.29
0.78 24.96
0.74 25.41
1.93 25.46
0.60 25.49
0.87 26.97
3.62 27.80
1.53 28.07
1.23 28.43
1.52 29.84
0.90 30.44
1.61 31.05
1.44 31.89
3.21 34.40
0.76 35.81

The average of the initial rest values was 2.02 and the average of the maximum peaks of 2.32 with an average value on the scale of 18.33.

It is possible to hypothesize that the scale found may constitute a significant marker for the measurement of pain.

Surely it will be necessary to carry out a test with a more precise protocol but it can be expected that the scale obtained can be proposed as a measure of pain.  Dividing Lagrange units by 10, we obtain the reference to the SEA really objective alongside the traditional surveys in use; this would result in a new unit of measurement to be validated at the proposed locations.

With regard  to the reliability of the test, the correlation between two homogeneous samples carried out at a week of difference was verified, with a degree of significance greater than 92%. In addition,  the verification test was carried out with respect to the average of 1.72 and also in this case the tests provided values above 90%. Comparing then the data obtained with the measurements of the sympathetic and parasympatheticsystem, carried out by detecting theinterbattito  in  ms, it was seen that at the stimulus there was activation of the coherent parasympathetic system.

From these elements also emerge implications in different areas, for example, themanagement of pain in sports which is a particularly current topic.

To better understand and manage pain, it is essential to understand what meaning the athlete attributes to it and for this reason a sports psychologist becomes a vital resource for an athlete.

In fact, it allows you to complete athletic, tactical and technical training with mental training, and manages all the psychological factors involved.

In this case, in fact, the psychological intervention favors the verbalization of pain thus stimulating the athlete’s awareness of his body.

The psychologist offers to listen to the problem, addressing it without neglecting the overall experience of the athlete.

It is therefore given full listening to all the concerns of the sportsman such as emotions of anger, fear, sadness and anxiety, welcoming and facing them, not repressing them but learning to manage them and transform them into motivating emotions.

It becomes essential to have tests and measurements in order to understand the situation at its best.

In this case, instrumental tests can be carried out through the measurement of skin conductance and in the psychological field there are abundant studies that go to research what are the personal characteristics that significantly impact on resilience.

In the psychological environment, the resilient person is the opposite of an easily harmed one. Psychological resilience is defined as: the ability to persist in pursuing challenging goals, effectively coping with difficulties and other negative events that will be encountered on the way.

Sport stimulates and empowers resilience in those who practice it for constant training to face their physical and psychological limits.

It may also be possible that you will find it difficult to overcome these limitations. The characteristic of the resilient personality consists of 4 elements:

  • Enduring frustrations: the ability to withstand difficulties and face an insurmountable obstacle, insisting on adapting to the situation.
  • Ingenuity in cognitive restructuring: it is about taking a different look when observing a particular event. For example, an injury is certainly a negative fact, but if you change the point of view you can see the opportunity to spend more time with your family, to have the opportunity to recover from physical efforts and find new stimuli to start again and return even stronger than before.
  • Perception of control: the athletes who enjoy it do not claim to dominate everything that surrounds them, they are aware that in sport unexpected events can often occur. Despite this, they are strongly confident in their abilities. This aspect is visible as natural, at the moment when there are drawbacks.
  • Predisposition to hope: When it seems that nothing can be done anymore, when events appear uncontrollable, the only thing that remains is hope, to have confidence that the situation will not remain forever like this, that something can happen that can allow the subject to redeem himself from a fleeting moment of crisis.

Pain is part of sport as you always have pressure to exceed your comfort limits.

What differentiates a great sportsman from an exceptional one is the limit beyond which pain is measured by the athlete as intolerable.

So what influences sports performance is the subjective perception of pain more than the actual pain.

For this reason, a work on the psychological part of pain can be very valuable, to be able to better manage all the factors that follow.

Doing so motivates the athlete to pursue goals and to train their resilience.

The resilient sportsman is that athlete who manifests the ability, taking advantage of his experience, to improvise when he is faced with an unexpected event, Interprets difficulties in a positive and challenging way, enjoys the strong certainty of being able to influence the situation in which he finds himself, welcomes his limits, finding new motivations to face challenges. Carrying out biofeedback work through the evaluation of conductance allows to better managepain, this through the measurement of pain through conductance.

Notes: the scale was named Lagrange as it was possible to carry out the tests and all the elaborations thanks to the IIS Lagrange school in Milan for the collaboration had by the School Director Prof. Militante, the vicar collaborator Prof. Tridico, Prof. Valpiani, the collaborators Giancarlo Ricci, Luca Antonio, Ivana Cavanna. The students of classes 4 electronics, 3 electronics, 4 sports high school, 4 computer science participated as a school-work alternation project actually working as company collaborators of the Proereal company that guided the work, both for the organization, both for the realization of all the tests, and for the processing of data


Bibiliography

Novak P(2017) Electrochemical skin conductance:a systematic review. Clin Auton Res.doi:https://doi.org/10.1007/s1028 6-017-0467-x .

Micropedia

THESIS: OBJECTIVE INFORMATIONAL BIOELECTRIC PROFILES PRELIMINARY DATA. Speaker PROF Sergio Serrano Candidate DOTT. Filippo Parodi; University of Eastern Piedmont

Article Republic: https://www.repubblica.it/tecnologia/2015/05/28/news/soddisfatto_o_arrabiato_il_sensore_per_valutare_l_efficienza_della_pa-115463006