Limbic Signal
Probing the Limbodic Frontier
Friday, February 10, 2023
Hyper-Hypo-Nose
Neural Cartography
"It is mind-blowing," said Dr. Lomvardas, also a professor of neuroscience and of biochemistry and molecular biophysics at Columbia's Vagelos College of Physicians and Surgeons. "This system found a way to create a genetically encoded, hard-wired means of transforming randomly-chosen receptor identity to a very precise target in the olfactory bulb."Perhaps, olfactory neurons are not alone in the way endoplasmic reticulum stress organizes their wiring with downstream neurons. "If it turns out that all neurons do this, this discovery could help us understand much more about the brain," said Shayya.
"The last frontier of sensory neuroscience"Because previous studies of the olfactory cortex failed to find any logical organization among neurons there, many neuroscientists suspected information about odors was relayed randomly through the brain. But those studies examined connectivity patterns of just a few dozen neurons.DNA-based brain-mapping technologies charting the way sensory information is routed between olfactory-processing parts of the brain including the olfactory bulb, which receives sensory information from the nose, the primary smell-processing hub called the piriform cortex, and several other brain regions that receive inputs from the olfactory bulb.
Friday, January 13, 2023
Smells Like Covid Part 2
Washing your hands with hydroalcoholic gel, smelling it and using a QR code to answer a short questionnaire. These very simple actions make up the world's first patented mass screening system for COVID cases.Citrus fruits and apples are two of the first aromas that people with the SARS-CoV-2 virus stop detecting.
"Citrus" -- I don't remember seeing this at all, so I looked further into the report: "Based on the literature and habits of our Mediterranean study population, it was determined that the most suitable odoriferous substance was lemon." via Institute for Research in Fundamental Sciences in Iran and R DOty at U Penn: Moein, S. T. et al. Smell dysfunction: A biomarker for COVID-19. Int. Forum Allergy Rhinol. 10, 944–950 (2020). https://pubmed.ncbi.nlm.nih.gov/32301284/ -- This study used the University of Pennsylvania Smell Identification Test (UPSIT) which has 40 odorants; I can't read the paper because paywall, but I guess "citrus" or "lemon" is one of those odors. The paper wasn't meant to find the most prevalent non-detectable odor, but I guess it was just sitting there in the data?
"The antigen tests on the market have an average sensitivity of 80%, which means that the number of false negatives is 20%. What we have developed is not a diagnostic test, but a screening system that aims to detect the maximum possible number of positives and prevent false negatives," explained the researchers.
They studied antibody levels in people infected during the early days of the pandemic—in all, they studied blood samples of 306 people who had donated blood for study after recovering from a COVID-19 infection. In comparing the antibody levels with other data provided by the donors and their doctors, the researchers determined that those people who had higher antibody levels tended to be the same people who had reported losing their sense of smell or taste. They found that such patients were twice as likely to lose one or the other sense as those who did not have higher-than-average levels of antibodies in their blood.
The reason some people fail to recover their sense of smell after COVID-19 is linked to an ongoing immune assault on olfactory nerve cells and an associated decline in the number of those cells, a team of scientists led by Duke Health report.
Using injections of platelet-rich plasma derived from a patient's own blood. In a trial of 26 participants, those who received the treatment were 12.5 times more likely to improve than patients who received placebo injections."It's a nerve damage and nerve regeneration issue that we're dealing with," she said.
Thursday, January 12, 2023
Mass Psychogenic Illness
- symptoms with no plausible organic basis;
- symptoms are transient and benign;
- symptoms with rapid onset and recovery;
- occurrence in a segregated group;
- the presence of extraordinary anxiety;
- symptoms that are spread via sight, sound or oral communication;
- a spread that moves down the age scale, beginning with older or higher-status people;
- a preponderance of female participants.
Three custodians working early Tuesday at Bergen Community College were overcome by chemical fumes and treated on site by paramedics, a college spokesman said.The incident occurred about 2 a.m. in a building at the campus on Paramus Road in Paramus. The custodians called emergency medical workers because they were concerned about breathing the fumes, the spokesman said.The spokesman said the smell was caused by a masking agent used to cover a chlorine smell from power-washing a day earlier and the air conditioner carried the masking agent smell throughout the building.
Fourteen participants in a soccer camp were taken to the hospital for observation Monday after they became sick while at a pool on Drew University’s campus in Madison, officials said.The campers experienced chlorine inhalation symptoms when “a small amount of chlorine was accidentally released” at the Simon Forum’s Pool shortly after noon, according to a statement from Madison officials.The soccer camp participants — ranging in age from 10 to 17 — received medical care at the scene and were taken to a local hospital within an hour, officials said.Tests at the pool showed normal levels of chlorine and all systems were working properly, according to a school spokesperson.Some campers reportedly smelled chlorine vapors and were vomiting in a nearby area. It was not immediately clear how the chemical was released, but there was no active leak.“Initial reports indicated that some of the children were suffering from shortness of breath, difficulty speaking between breaths, nausea and general airway issues,” said Morris County Emergency Management Director Jeffrey Paul.
I recall an event when workers were cutting through an old cooling water intake from the Hudson River and a strong odor resulted in having to evacuate the building until it was determined that the odor was from torching zebra mussels that had lined the inner surface of the intake!
- 1) involvement - the extent to which workers are enthusiastic or committed to their jobs;
- 2) peer cohesion - the extent to which workers are mutually supportive;
- 3) staff support - the extent to which management is perceived as supportive by the workers;
- 4) autonomy - the extent to which the workers feel self-sufficient and independent;
- 5) task orientation - the extent to which the climate emphasizes productivity and efficiency;
- 6) work pressure - the extent to which workers perceived pressure to produce;
- 7) clarity - the extent to which workers know what is expected of them in the perform- ance of their jobs;
- 8) control - the extent to which management imposes rules and regulations on the workers;
- 9) innovation - the extent to which variety and new approaches are emphasized in the workplace; and
- 10) physical comfort - the extent to which the physical surroundings contribute to a pleasant work environment. [19] Moss AH, Insel PM, Humphrey B: Family Work and Group Environment Scales Manual. Palo Alto, Consulting Psychologists Press, Inc, 1974.
- *Needs: more cohesiveness, more support, less work pressure, more control, less ambiguity of work role; physical comfort is actually negligible.
- Environment: organized, structured, clear roles, not voluntary, ie, stress daily, escape limited
- Boredom: repetitive tasks
- Production pressure: forced overtime, deadlines
- Physical stressors: noise, lighting, thermal comfort, odors (hypersensitivity?)
- Labor-management relations: lack of trust
- Communication: scheduled break times means no meeting friends, noisy means can't hear
- Wheeler, L. (1966). Towards a theory of behavioural contagion. Psychological Review, 73:179-192.
- Kerckhoff, A.C. and Back, K.W. (1968). The June Bug: A Study in Hysterical Contagion. New York: Appleton-Century-Crofts.
- Stahl SM, Lebedun M: Mystery gas: An analysis of mass hysteria. J Health Soc Behav 15:44-50, 1974.
- Mechanic D: Discussion of research on relations between stressful life events and episodes of physical illness, in Dohrenwend BS, Dohrenwend BP (eds): Stressful Life Events: Their Nature and Effects. New York, John Wiley& Sons, Inc, 1974.
- Freedman, J.L., and Perlick, D. (1979). Crowding, contagion and laughter. Journal of Experimental Psychology, 15:295-303.
- Freedman, J.L. (1982). Theories of Contagion as they relate to mass psychogenic illness. In M.J. Colligan, J.W. Pennebaker, and L.R. Murphy (eds.) Mass Psychogenic Illness, N.J: Erlbaum, 171-182.
- Turner, R.H. and Killian, L.M.(1987). Collective Behavior (3rd ed.) NJ: Prentice-Hall.
- Goodenough, O. R. and Dawkins, R. (1994). The "St. Jude" mind virus. Nature, 371:23-24 (ask Nature; they'd like you to rent a roughly 30 year old article for $8.99).
- Jones, M.B., and Jones, D.R. (1995). Preferred pathways of behavioural contagion. Journal of Psychiatric Research, 29:193-209. [Danish twins study, more about criminality, also more about genetics vs contagion.]
Wednesday, November 30, 2022
Living With Friends
An experimental test home was erected in Austin, Texas during the summer of 2018. The house was designed for ordinary use and included bathrooms, a kitchen, gathering and work areas. Overnight stays were prohibited, but 45 study participants, plus visitors, spent time in the house, occupying it for approximately six hours per day for 26 days, during which they performed scripted activities, such as cooking, cleaning and socializing.The house was deep cleaned with a bleach solution. Nonetheless, researchers said traces of molecules associated with humans were still present. After almost of month of human occupation, the house was alive with molecular and microbial abundance and diversity, albeit unevenly distributed.Not surprisingly, the kitchen and toilet were hotspots of molecular and microbial diversity, though numbers fluctuated with surface cleaning and sanitation. "It appears that, even when a subset of chemistry is removed because of the cleaning, it is only temporary and/or partial, as the sum total of cleaning and human activities overall results in an increase in accumulation of richer chemistry," the authors wrote.
- Teachers did not accurately perceive mechanical ventilation sufficiency
- Air quality and temperature are conflated
- Dramatic difference in IAQ perception (but not quality) in summer vs winter
- Occupants misperceive temperature as a proxy for indoor air quality; they think cooler air is better, and confuse warm air with "stuffy, stale" air
- Teachers in classrooms with worse ventilation were more satisfied with classroom temperature
- Occupants don't understand how the systems work, and think incoming cold air in winter is a defect, for example (when in fact it is the system adding fresh air to the mix); they then say the system isn't working, and therefore they must have bad IAQ; they also think the only time the system brings fresh air is when the AC is on, which is the complete opposite of what's happening
Thursday, November 17, 2022
Everyone Likes Vanilla
Odor preference is molecular. People share odor preferences regardless of cultural background. Traditionally it has been seen as cultural.
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Girl Smelling a Flower in Profile - Petr Kratochvil |
Department of Clinical Neuroscience at Karolinska Institutet, School of Life Sciences at Arizona State, Centre for Languages and Literature at Lund, Department of Anthropology at University College London, Colegio de Ciencias Sociales y Humanidades at Universidad San Francisco de Quito in Ecuador, Instituto de Investigaciones Filológicas at the National Autonomous University of Mexico, School of Languages and Linguistics at University of Melbourne, Monell Chemical Senses Center, Department of Neuroscience at University of Pennsylvania (Asifa Majid as corresponding author)
Many of the researchers are field workers working with indigenous populations. For this present study, the researchers selected nine communities representing different lifestyles: four hunter-gatherer groups and five groups with different forms of farming and fishing. Some of these groups have very little contact with Western foodstuffs or household articles."Since these groups live in such disparate odiferous environments, like rainforest, coast, mountain and city, we captured many different types of 'odor experiences'," says Dr. Arshamian.
The study included a total of 235 individuals, who were asked to rank smells on a scale of pleasant to unpleasant. The results showed variation between individuals within each group, but global correspondence on which odors are pleasant and unpleasant. The researchers showed that the variation is largely explained by molecular structure (41 percent) and by personal preference (54 percent).
The odors the participants were asked to rank included vanilla, which smelled best. This was followed by ethyl butyrate, which smells like peaches. The smell that most participants considered the least pleasant was isovaleric acid, which can be found in many foods, such as cheese, soy milk and apple juice, but also in foot sweat.
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AI Art - Emma Watson in a Tunic Holding a Flower by Rubens - 2022 Emma Watson wearing green tunic holding a flower. Painted by Rubens, high detail [link] |
Thursday, November 10, 2022
The Past Doesn't Smell Like It Used To
Advanced biomolecular and ‘omics’ sciences enable more direct insights into past scents, offering new options to explore critical aspects of ancient society and lifeways as well as the historical meanings of smell.
Odeuropa is a European research project which bundles expertise in sensory mining and olfactory heritage. We develop novel methods to collect information about smell from (digital) text and image collections.