-
Categories
-
Pharmaceutical Intermediates
-
Active Pharmaceutical Ingredients
-
Food Additives
- Industrial Coatings
- Agrochemicals
- Dyes and Pigments
- Surfactant
- Flavors and Fragrances
- Chemical Reagents
- Catalyst and Auxiliary
- Natural Products
- Inorganic Chemistry
-
Organic Chemistry
-
Biochemical Engineering
- Analytical Chemistry
-
Cosmetic Ingredient
- Water Treatment Chemical
-
Pharmaceutical Intermediates
Promotion
ECHEMI Mall
Wholesale
Weekly Price
Exhibition
News
-
Trade Service
Written byJia Yugeng EditorWang Duoyu TypesettingShui Chengwen
It is well known that humans and animals obtain external information through a variety of sensory pathways, including touch, which is an important sensory function
when living organisms are in direct contact with the external environment.
When we feel discomfort in a certain part of our body, we usually instinctively apply some pressure to that part of the touch (vibrating hapability).
For example, when you have a headache, rub your temples for a while, and the feeling of pain will decrease; Or, when there is pain in the abdomen, covering the stomach is the most common analgesic behavior
.
For neuroscientists, however, the specific mechanism of this phenomenon, known as tactile analgesia
, remains elusive.
Recently, a research team led by Wang Fan, professor of the Department of Brain and Cognitive Science at the McGovern Institute of the Massachusetts Institute of Technology, published a report entitled Science Advances Research paper on Somatosensory cortical signature of facial nociception and vibrotactile touch–induced analgesia.
The study sheds light on the complex relationship between pain and touch in depth and provides some new insights
into chronic pain-related diseases in humans.
Pain is a complex sensory and emotional experience that can be altered
by higher-order processing.
Previous neurophysiological studies of anesthetized animals by Wang Fan's team found that the presence of a class of wide dynamic range neurons (WDRs) in the spinal cord may be touch-mediated analgesic
substrates.
In humans, touch-mediated pain relief has been shown to work on body parts innervated by dorsal root ganglion (DRG) and orofacial regions innervated by trigeminal ganglion (TG) neurons.
The signals of pain-responsive neurons are weakened
by vibrating the sense of touch.
There are also indications that this process may be related to
the cerebral cortex.
However, which cortical areas are involved is unclear
.
Professor
Wang Fan said that although mice have been known to respond to painful stimuli in the face, such as wiping their faces with paws, But it was not possible to track specific pain responses in their brains to determine whether the behavior helped relieve pain
.
This aspect of the response remains largely unexplored because it is difficult to monitor the brain's response to painful stimuli across all neural activities, especially when the animal moves, where signals from movement and touch have completely overridden other potential pain signals
.
In the new study, instead of studying the effects of scratching faces in mice, they focused their attention on a more subtle tactile approach, developing a model of mouse behavior mediated by vibrational tactile inhibition of nociception
.
Typically, rodents use beards as the primary tactile sensor
for the face.
During environmental exploration, mice move their whiskers back and forth at regular and high frequencies, a process known as whisking, to gather sensory information
in various environments.
Each whisker on the rodent's nose is represented separately in the barrel-like cortex (S1B) of the primary somatosensory cortex, which is used to process the tactile information
produced by the beard.
In experiments, the research team applied radiant heat or harmful mechanical stimulation
to the left beard pad on the faces of mice.
Mice rub their faces
based on the intensity of the perceived nociceptive stimulus.
The researchers took this behavior as a signal
of nociceptive perception.
They found that when the beards of the mice "flicked," they responded significantly less to harmful heat or mechanical stimuli (the number of wipes on their faces) compared to mice whose beards were not "flicked.
"
。 Similarly, under conditions of spontaneous beard movement, mice were significantly less likely to wipe their
faces.
When the beard of the mice "flicked," those cells that preferentially responded to nociceptive heat and mechanical stimuli activated less
frequently.
As a result, they are less likely to respond to
painful stimuli.
The team also found that even though mice with "flicked" beards wiped their faces under painful stimuli, neurons in the brain needed more time to adjust to the firing patterns
associated with wiping motion.
The effect of "flicking" on pain signals appears to rely on a special touch processing circuit that sends tactile information from the posterior medial nucleus (VPM) of the thalamus to the barrel-shaped cortex (S1B) of the primary somatosensory cortex
。 When the researchers blocked this pathway, "flicking" would no longer inhibit the animal's response
to the painful stimulus.
Wang Fan noted that even a fraction of a second before the exraged mice began wiping their faces, when the animals were relatively stationary, it was difficult to distinguish which brain signals were associated with perceiving nociceptive heat or mechanical stimuli.
Which are associated
with the "flicking" of the beard.
Subsequently, the research team developed signal separation algorithms that can break down calcium signals into sensation-induced, "flicking" or wiping facial responses, and found that the presence of "flicking" alters nociceptive signal processing
in S1B neurons.
Analysis of S1B dynamics suggests that "flicking" promotes a shift
in neurological status caused by noxious stimuli to the outcome of nonnociceptive behavior.
Thus, S1B integrates facial haptics and noxious signals for touch-mediated analgesia
.
Wang says the team is eager to know how this circuit works with other parts of the brain to regulate perception and response
to painful stimuli.
In addition, these findings may be related to thalamic pain syndrome, a chronic pain disorder that occurs after a stroke affects the cerebral thalamus
.
Wang Fan said that stroke may impair the function of the thalamic circuit, which usually transmits pure tactile signals and inhibits pain signals
transmitted to the cerebral cortex.
Link to the paper: style="letter-spacing: normal;font-size: 12px;color: rgb(136, 136, 136);" _mstmutation="1" _istranslated="1">
Open reprint, welcome to forward to Moments and WeChat groups
It is well known that humans and animals obtain external information through a variety of sensory pathways, including touch, which is an important sensory function
when living organisms are in direct contact with the external environment.
When we feel discomfort in a certain part of our body, we usually instinctively apply some pressure to that part of the touch (vibrating hapability).
For example, when you have a headache, rub your temples for a while, and the feeling of pain will decrease; Or, when there is pain in the abdomen, covering the stomach is the most common analgesic behavior
.
For neuroscientists, however, the specific mechanism of this phenomenon, known as tactile analgesia
, remains elusive.
Recently, a research team led by Wang Fan, professor of the Department of Brain and Cognitive Science at the McGovern Institute of the Massachusetts Institute of Technology, published a report entitled Science Advances Research paper on Somatosensory cortical signature of facial nociception and vibrotactile touch–induced analgesia.
The study sheds light on the complex relationship between pain and touch in depth and provides some new insights
into chronic pain-related diseases in humans.
Pain is a complex sensory and emotional experience that can be altered
by higher-order processing.
Previous neurophysiological studies of anesthetized animals by Wang Fan's team found that the presence of a class of wide dynamic range neurons (WDRs) in the spinal cord may be touch-mediated analgesic
substrates.
In humans, touch-mediated pain relief has been shown to work on body parts innervated by dorsal root ganglion (DRG) and orofacial regions innervated by trigeminal ganglion (TG) neurons.
The signals of pain-responsive neurons are weakened
by vibrating the sense of touch.
There are also indications that this process may be related to
the cerebral cortex.
However, which cortical areas are involved is unclear
.
Professor
Wang Fan said that although mice have been known to respond to painful stimuli in the face, such as wiping their faces with paws, But it was not possible to track specific pain responses in their brains to determine whether the behavior helped relieve pain
.
This aspect of the response remains largely unexplored because it is difficult to monitor the brain's response to painful stimuli across all neural activities, especially when the animal moves, where signals from movement and touch have completely overridden other potential pain signals
.
In the new study, instead of studying the effects of scratching faces in mice, they focused their attention on a more subtle tactile approach, developing a model of mouse behavior mediated by vibrational tactile inhibition of nociception
.
Typically, rodents use beards as the primary tactile sensor
for the face.
During environmental exploration, mice move their whiskers back and forth at regular and high frequencies, a process known as whisking, to gather sensory information
in various environments.
Each whisker on the rodent's nose is represented separately in the barrel-like cortex (S1B) of the primary somatosensory cortex, which is used to process the tactile information
produced by the beard.
In experiments, the research team applied radiant heat or harmful mechanical stimulation
to the left beard pad on the faces of mice.
Mice rub their faces
based on the intensity of the perceived nociceptive stimulus.
The researchers took this behavior as a signal
of nociceptive perception.
They found that when the beards of the mice "flicked," they responded significantly less to harmful heat or mechanical stimuli (the number of wipes on their faces) compared to mice whose beards were not "flicked.
"
。 Similarly, under conditions of spontaneous beard movement, mice were significantly less likely to wipe their
faces.
When the beard of the mice "flicked," those cells that preferentially responded to nociceptive heat and mechanical stimuli activated less
frequently.
As a result, they are less likely to respond to
painful stimuli.
The team also found that even though mice with "flicked" beards wiped their faces under painful stimuli, neurons in the brain needed more time to adjust to the firing patterns
associated with wiping motion.
The effect of "flicking" on pain signals appears to rely on a special touch processing circuit that sends tactile information from the posterior medial nucleus (VPM) of the thalamus to the barrel-shaped cortex (S1B) of the primary somatosensory cortex
。 When the researchers blocked this pathway, "flicking" would no longer inhibit the animal's response
to the painful stimulus.
Wang Fan noted that even a fraction of a second before the exraged mice began wiping their faces, when the animals were relatively stationary, it was difficult to distinguish which brain signals were associated with perceiving nociceptive heat or mechanical stimuli.
Which are associated
with the "flicking" of the beard.
Subsequently, the research team developed signal separation algorithms that can break down calcium signals into sensation-induced, "flicking" or wiping facial responses, and found that the presence of "flicking" alters nociceptive signal processing
in S1B neurons.
Analysis of S1B dynamics suggests that "flicking" promotes a shift
in neurological status caused by noxious stimuli to the outcome of nonnociceptive behavior.
Thus, S1B integrates facial haptics and noxious signals for touch-mediated analgesia
.
Wang says the team is eager to know how this circuit works with other parts of the brain to regulate perception and response
to painful stimuli.
In addition, these findings may be related to thalamic pain syndrome, a chronic pain disorder that occurs after a stroke affects the cerebral thalamus
.
Wang Fan said that stroke may impair the function of the thalamic circuit, which usually transmits pure tactile signals and inhibits pain signals
transmitted to the cerebral cortex.
Link to the paper: style="letter-spacing: normal;font-size: 12px;color: rgb(136, 136, 136);" _mstmutation="1" _istranslated="1">
Open reprint, welcome to forward to Moments and WeChat groups
