NeuroStories 2021: answers to questions

The discovery of little-known senses of the human body during the event of the NeuroStories 2021 on November 25 of 2021, entitled “Beyond the five senses”, sparked curiosity among the public on-site and online. Each presentation of our speakers Felipe Pegado, Valérie Jessica Laporte, Henry Evrard, Edith Ribot-Ciscar and Aziz Moqrich, raised a batch of questions. Some of them could be answered at the end of the presentation, but some remained unanswered while being interesting.

In this article, find the replay of our speaker’s intervention with unanswered questions.

Questions:

Q: Is the type of training you are studying, to improve learning to read, already used by speech-language pathologists? (targeted education method)

• No, it is a new method, targeted on this specific visual difficulty (the ‘mirror confusion’ for letters). Maybe it will become a common practice in the years to come, in schools or in speech therapists, but we are not there yet. This method was built from my hypothetical model of ‘mutual aid’ between various sensorimotor systems. This model can be viewed on wikipedia. A description of the method can be found on our original publication, or in a little more detail on a new publication (both open access).

Q: What about glasses for dyslexics (ex: Atol)? Does it work? Is it scientifically based?

• Apart from anecdotal comments that can be found on the internet, I am not aware of any clinical research evaluating this tool.

Questions:

Q: Is your perception of music, associated with geometric representations, a form of synesthesia?

• Yes, but it’s not a very impressive form of synesthesia, unlike some people who mention seeing almost works of art being born from music. When I experience a particularly joyful emotion or relief, the colors suddenly become excessively saturated. It’s kind of the same principle.

Q: How do you manage to have a family life in your situation? In terms of couple relationships, pregnancy, childbirth, baby care…?

• The childbirth, at least the first one, caused a post-traumatic shock. I didn’t have the right support, and at the same time, if I had asked for what I needed, I would have been afraid of having the social services on my back. So I preferred to do it alone, which didn’t go so well. The child did not lack anything but my psychological and physical state deteriorated. On the other hand, the three pregnancies were traumatic. Having the body invaded was very difficult, as well as finding a balance. I was trying to follow the baby instruction book perfectly, in an obsessive way. I think some non-judgmental, non-pressure coaching would have helped.
  With the other two children, I had a spouse, and balance between the two of us was the answer. We are opposite temperaments, so we complement each other beautifully. The strengths of one are the challenges of the other. Adaptation I have to make, in my environment, in my ways of functioning, is very different from others, my needs are different. When I was able to understand and respond to my needs, everything fell into place.

Questions:

• Unfortunately, due to his important missions in Shangaï, Mr Henry Evrard couldn’t be available to respond our questions.

Questions:

Q: Concerning people with proprioceptive impairments, are their pressure receptors functional and if so, can they represent a form of feedback in this case? (pressure of the feet on the ground for example)

• People who are deprived of proprioception owe it to a damage of the sensory nerve fibers of large diameter (afferent fibers Ab). It is also this type of fiber that carries the information from the tactile receptors and in particular the pressure receptors. Therefore, this plantar skin pressure information is no longer transmitted in this pathology, as is the information coming from the muscle receptors (neuromuscular spindles).

Q: What is the explanation for phantom limb sensations in affected individuals?

• Phantom limb sensations are due to the maintenance of a cortical representation of the amputated limb. This persistence of sensations of the missing limb very often generates phantom pain, the origin of which is still debated, but it would seem that the disappearance of sensory and motor connections plays a determining role in their genesis and maintenance.

Q: Can proprioception explain why music can be the source of emotions in people with hearing loss?

• I did not know that people without hearing could be sensitive to music. If this is the case, I would suggest that it is related to the high sensitivity of muscle and skin receptors (especially Pacini receptors) to mechanical vibrations. Music, by vibrating the skeleton, is a source of excitation that is transmitted to the brain and this can generate sensations such as feelings of pleasure.

Questions:

Q: Is there a relationship between proprioception and TRPV1 receptors?

• No relationship between TRPV1 and proprioception. TRPV1 is expressed only in nociceptive neurons. In mice, inactivation of TRPV1 has no effect on proprioception.

Q: If we all have nociceptors, why do some people “resist” pain better? Are some nociceptors more efficient than others? Or less? Is it happening at another level?

• The difference in pain tolerance can have several origins: physiological, cultural and in some cases it can be related to gender.For the physiological aspect: yes, there may be people who are more resistant to painful stimuli because of genetic or epigenetic modifications that cause an increase in the activation threshold of their nociceptors. Example of people with a mutation leading to a decrease in the function of the Nav 1.7 channel, an ion channel responsible for the generation of action potentials in the nociceptors. There are many other examples.For the cultural aspect, the perception of pain depends on the experience, the social situation, the beliefs…. Let’s remember the definition of pain according to the International Association for the Study of Pain: pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of that damage. The term “emotional” is worth considering.For the pain and gender aspect, there is clearly a prevalence of chronic pain in women than in men. For example, 80% of fibromyalgia patients are women. The same is true for migraines and many other pain conditions.Does this mean that women are more sensitive to pain than men? The answer is not entirely clear. The pain threshold is lower in women, but women seem to tolerate pain better than men.Our understanding of the mechanisms underlying gender-specific pain has long suffered from the fact that 90% of animal studies have been conducted in males. Over the past decade, it has become mandatory to include males and females in all pain studies.

Q: Could the transmission of pain, in the path of information from touch to the brain, be involved in fibromyalgia?

• Absolutely. Although the origin of this extremely disabling pathology is not yet known, when you have pain that appears without any lesions or other traumas, it is because the transmission pathway of the sensory information to the brain is affected. There is a theory described in 1965, and which remains valid to this day, which states that when a tactile stimulation is perceived as painful, it is because the door to the pain pathway has been opened. The opening of this door is done at the level of the spinal cord which is the first integrating center of all the sensory information that emanates from the environment (external or internal).

The NeuroStories of NeuroMarseille is the flagship public event of our institute, we are very happy and proud to be able to present it every year. Thanks to your curiosity, the NeuroStories of 2021 will continue to live and bring more light to our community and beyond!

To review the entire event and the live answers from our speakers, you can watch the video below and go at 1:47:37, or directly access to this moment of the video on our Youtube channel.

We would like to thank all our speakers, our audience and the members of the organization for this great success and hope to see you next year!