The human evasion reaction to unsavory scents related to risk has for some time been viewed as a conscious cognitive process. However, the research from Karolinska Institutet shows that it is an unconscious and fast reaction. The brain processes involved in the translation of an unpleasant odor into avoidance behavior in humans have long remained a mystery. The lack of non-invasive methods to measure signals from the olfactory bulb is one of the reasons for such development (Karolinska Institutet, 2021).
The olfactory bulb is the initial section of the rhinencephalon. It has direct links to crucial elements of the central nervous system that help in the detection and recall of potentially harmful circumstances and chemicals (Karolinska Institutet, 2021). After being breathed through the nose, odor impulses reach the brain in 100 to 150 milliseconds (Karolinska Institutet, 2021). The olfactory sense appears to be especially crucial in humans for identifying and responding to potentially hazardous stimuli.
Researchers at Karolinska Institutet have devised a method for measuring signals from the human olfactory bulb. It analyzes odors and provides signals to areas of the brain that regulate movement and avoidance behavior (Karolinska Institutet, 2021). Their findings are based on three tests in which individuals were asked to score their reactions to six distinct odors, some of which were good and some of which were negative, while the electrical activity of the olfactory bulb was monitored (Karolinska Institutet, 2021).
The individual automatically leans back and away from the source of the odor as a result of the signal (Karolinska Institutet, 2021). These results imply that human sense of smell is vital in detecting threats within environment, and that most of this capacity is more unconscious than the reaction to danger mediated by eyesight and hearing.
Questions: What kind of utilities researchers utilized in order to monitor electrical activity of participants? What are the other senses that function as the threat detector?
Reference
Karolinska Institutet. (2021). Sense of smell is our most rapid warning system. ScienceDaily. Web.