Harnessing the Smell of Fear

The release of “alarm molecules” is a subject has been well-researched and well-documented over the years. In Chapter 6 of Whiff!, we learn that “animals experiencing stress and fear produce chemical warning signals that can lead to behavioral and physiological responses in members of the same species. For instance, if a herd member were under attack, the animal would release a scented fear message to the others, warning the entire herd to flee as fast as dominoes may fall.” But what part of the olfactory system of the animal on the receiving end is responsible for detecting this crucial chemical message? The same component which allows them to perceive and identify odorants? Or maybe the vomeronasal organ which serves to detect sexual pheromones?

Neither, confirms a recently-concluded study from the University of Lausanne in Switzerland. It’s a third subsystem of the olfactory system, the Grueneberg ganglion, which is responsible for detection of “fear Read more

Paternal In-stinks

Innumerable studies have explored the olfactory bonding between new moms and their babies, but what about new dads? Are they geared to think with their olfactory organs, with respect to their own offspring?

Absolutely, according to a new study by the Wisconsin National Primate Research Center at University of Wisconsin-Madison, at least in the case of lower primates. A whiff of his own little tyke will cause a marmoset father’s testosterone levels to drop off, lowering both his tendency toward aggressive behavior and his interest in philandering.

“Essentially, this encourages the father to be there for the child,” says WNPRC staff scientist Dr. Toni Ziegler, whose team conducted the study by isolating experienced male marmoset fathers from their families, then exposing them to either the scent of their own infants or a control scent. Males with no experience as parents were exposed to the same odors. Blood tests taken within 20 minutes of exposure revealed a significant decline in testosterone in every single one of the experienced dads presented with the odor of their own offspring, while the bachelor marmosets were completely indifferent. “We were a little surprised to see testosterone alter like that,” admits Ziegler. “This shows the male is responsive to chemical cues from his infants.”

Testosterone is the most abundant male hormone in primates, including humans. And marmosets, small South American monkeys, were a prime-primate choice for the experiment because they, like humans, tend to place nearly as much parental responsibility on the father as the mother.

The Science of Olfactory Diagnosis

The smell of rotten apples on a patient’s breath doesn’t positively indicate diabetes, and fishy breath doesn’t positively indicate liver disease–any more than the smell of Smirnoff positively indicates alcoholism–but it can give a physician Read more

A Proactive Approach to Parkinson’s Disease

The University of Pennsylvania Smell Identification Test (UPSIT) is the most widely used–and useful–clinical olfactory test in the world. Developed and practiced at the university’s renowned Smell and Taste Center, the UPSIT consists of four booklets containing ten microencapsulated odors, each accompanied by four possible responses from which the participant is asked to choose. Studies using the UPSIT have positively linked olfactory dysfunction to a variety of causes ranging from head trauma and respiratory infection to neurological disorders like Alzheimer’s and Parkinson’s disease. The value of the test in Read more

Eradicating Hepatitis B with the Mucosal Vaccine

Even with the existence of effective vaccinations, hepatitis B continues to kill more than a million people each year. Traditional injected vaccines present challenges which are particularly cumbersome in developing nations, including the need for a supply of sterile needles, constant refrigeration, and three separate treatments. Such obstacles may soon be a thing of the past, according to a new study on a nasal hepatitis B vaccine which require no needles, refrigeration, or multiple doses. But is it effective? In a word, Yes. The mucosal vaccine triggered an astounding protective response in animals roughly 450 times greater than that of currently approved vaccines, producing three distinct types of immunity–mucosal, cellular and systemic.

Mucosal vaccines are delivered directly to the lining of the nose where immune cells recognize the foreign antigen, causing rapid stimulation of the immune system, and do not involve the inflammatory chemicals used in injected vaccines. “We have developed a new vaccine that is extremely safe, easy to administer, and which rapidly builds protection against hepatitis B infection,” said Dr. James R. Baker Jr., founder of NanoBio Corp, which has exclusive rights to commercialize the new vaccine technology. Read more

Simple Testing for Little Noses

With increasing evidence that an impaired sense of smell can be an early indicator of everything from sinus and ear infection to schizophrenia and Alzheimer’s disease, development of accurate methods of measuring olfactory function has become a diagnostic priority. While effective clinical tests are in use for adults, such as the OLFACT, most are considered unsuitable for children because they tend to test for a complex range of smells unknown to a child.

Recognizing the need for testing on a more “Fun With Dick and Jane” level, researchers from the University of New South Wales have developed a simplified odor identification test involving 16 common odorants (such as fish, cut grass, and chocolate) and simple visual images geared toward children aged five to seven. Study participants sniffed the odors from individual plastic bottles, then viewed three photographs and picked the one that best represented the smell. 88.1% of five-year-olds, 88.9% of six-year-olds, and 91.1% of seven-year-olds correctly identified the smells. For a five-year-old, say the researchers, normal olfaction would be defined by correct identification of 11 out of the 16 odors, and anosmia would be signaled by correct identification of 4 or less.

While early results are extremely promising, the researchers point out that “as yet no data have been obtained from children with diseases or injuries using the tests which would provide the ranges of identification scores that define hyposmic and anosmic individuals, and the equivalent ranges for those with gustatory dysfunctions. Clearly, this is a priority before the tests can be fully utilized by clinicians when diagnosing chemosensory dysfunctions.”

Forensic Pathology Device Sniffs Out Dead Air

“The Body Farm,” as the University of Tennessee Forensic Anthropology Facility has been known since inspiring Patricia Cromwell’s novel, was opened in 1971 by Dr. William Bass, who recognized the need for research into human decomposition after police repeatedly asked for his help analyzing bodies in criminal cases. What began as a small patch of land where one body was allowed to decompose in the open air for the sake of science has developed into a 3-acre complex that contains remains of around 40 individuals at any given time. Now, the Knoxville facility has been recruited by Orange County detectives for help in their continuing investigation into the disappearance of toddler Caylee Anthony.

After cadaver dogs responded to an odor emitting from the white Pontiac found abandoned by the child’s mother, Orlando investigators tapped The Body Farm for assistance in testing air samples from the trunk of the car. Using a sort of “artificial nose” which pulls air through a tube into a spectrometer chamber, the scientists will be looking for the presence of certain chemical compounds that are released only by a decomposing body. “After we die and the bacteria proliferate in our body and start breaking down our Read more

Sniffing Out Genetic Risk Markers

Olfactory defects may indicate a genetic predisposition to schizophrenia, even in the absence of any other symptoms, according to a study concluded last month at the University of Pennsylvania.

Bruce Turetsky and his team made the astonishing discovery that the olfactory bulbs of first-degree relatives of schizophrenia patients are smaller in volume than those of individuals with no family history of the disease. When the scientists compared the brain activity of 14 unaffected direct relatives of schizophrenia patients against a 20-subject control group, they discovered significant impairment of scent detection and identification in the first group.

“While these findings must be considered preliminary,” concluded the researchers, “they are consistent with the conclusion that neurophysiological disturbances in the olfactory system may be sensitive endophenotypic markers (characteristics that reflect the actions of genes predisposing an individual to a disorder) of genetic vulnerability to schizophrenia.”

How Well Do You Smell?

Knowing whether or not you smell good isn’t so tricky. As a rule of thumb, if humans display an obvious aversion to your armpits and dogs display an obvious interest in them, it may be time to break out the Mister Bubble. But knowing whether or not you smell well is another matter. As with vision and hearing, the sense of smell is subjective. With no point of reference, an individual is unable to perceive a decline in these senses.

Dr. Allen Seiden is part of a team currently testing the Olfactory Function Assessment with Computerized Testing machine (OLFACT), which objectively measures an individual’s ability to smell. The machine emits a scent through a tube beneath the patient’s nose then prompts him to identify the scent on a computer screen. “It’s basically plumbing, just blowing into the air are odorized vials that contain the odorant, and that contains all the different smells the patients have to smell,” says design specialist and OLFACT creator Lloyd Hastings.

The new machine, expected to be marketed soon for nationwide use, may prove every bit as valuable as those already in mainstream use for testing vision and hearing. Not only do we rely on our noses to enhance our sense of taste, to alert us to danger, and Read more

Flies That Can’t Smell just Can’t Tell

Just how important is a good sense of smell in matters of romance? Well, for male fruit flies, it’s so vital that the absence of just a single olfactory gene renders them as indiscriminate in matters of courtship as my cousin Freddie (no offense, Freddie).

Scientists at Duke University Medical Center have found that male fruit flies without the gene Gr32a, a critical pheromone receptor, were sexually outperformed by four to one in comparison with normal male competitors. They also tended to court females which had been doused with male pheromones, behavior not observed in normal fruit flies because females which smell of male pheromones have presumably already mated. In fact, the hapless Gr32a-impaired flies were just as happy to court the male competitors themselves.
Read more

« Previous Page — Next Page »